<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE book PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN" "http://docbook.org/docbook/xml/4.5/docbookx.dtd" [
<!ENTITY url_refdocs_base_glib_html "http://developer.gnome.org/glibmm/2.50/">
<!ENTITY url_refdocs_base_glib "&url_refdocs_base_glib_html;classGlib_1_1">
<!ENTITY url_refdocs_base_gio "&url_refdocs_base_glib_html;classGio_1_1">
<!ENTITY url_refdocs_base_gtk_html "http://developer.gnome.org/gtkmm/3.22/">
<!ENTITY url_refdocs_base_gtk "&url_refdocs_base_gtk_html;classGtk_1_1">
<!ENTITY url_refdocs_base_gtk_namespace "&url_refdocs_base_gtk_html;namespaceGtk_1_1">
<!ENTITY url_figures_base "figures/">
<!ENTITY url_examples_base "http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/">
<!ENTITY url_examples_branchsuffix "gtkmm-3-22">
<!ENTITY gtkmm "<application>gtkmm</application>">
<!ENTITY uuml "&#252;">
<!ENTITY szlig "&#223;">
<!ENTITY verbar "&#124;">
<!ENTITY copy "&#169;">
<!ENTITY nbsp "&#160;">
]>
<!--
NOTE TO TUTORIAL DOCUMENTATION AUTHORS:
When referring to the gtkmm project in this document, please use the form
&gtkmm; so that the name is consistent throughout the document. This will wrap
gtkmm with <application></application> tags which can then be styled by CSS if
desired (e.g. boldface, monospace, etc) to make it stand out as the project
name
-->
<!-- The XSL for developer.gnome.org requires this id. -->
<book id="index" lang="fr">

  <bookinfo>

    <title lang="en">Programming with <application>gtkmm</application> 3</title>

    <authorgroup>
      <author lang="en">
        <firstname>Murray</firstname>
        <surname>Cumming</surname>
      </author>
      <author lang="en">
        <firstname>Bernhard</firstname>
        <surname>Rieder</surname>
        <contrib>Chapter on "Timeouts".</contrib>
      </author>
      <author lang="en">
        <firstname>Jonathon</firstname>
        <surname>Jongsma</surname>
        <contrib>Chapter on "Drawing with Cairo".</contrib>
        <contrib>Chapter on "Working with gtkmm's Source Code".</contrib>
        <contrib>Chapter on "Recent Files".</contrib>
      </author>
      <author lang="en">
        <firstname>Ole</firstname>
        <surname>Laursen</surname>
        <contrib>Parts of chapter on "Internationalization".</contrib>
      </author>
      <author lang="en">
        <firstname>Marko</firstname>
        <surname>Anastasov</surname>
        <contrib>Chapter on "Printing".</contrib>
        <contrib>Parts of chapter on "Internationalization".</contrib>
      </author>
      <author lang="en">
        <firstname>Daniel</firstname>
        <surname>Elstner</surname>
        <contrib>Section "Build Structure" of chapter
          on "Wrapping C Libraries with gmmproc".</contrib>
      </author>
      <author lang="en">
        <firstname>Chris</firstname>
        <surname>Vine</surname>
        <contrib>Chapter on "Multi-threaded programs".</contrib>
      </author>
      <author lang="en">
        <firstname>David</firstname>
        <surname>King</surname>
        <contrib>Section on Gtk::Grid.</contrib>
      </author>
      <author lang="en">
        <firstname>Pedro</firstname>
        <surname>Ferreira</surname>
        <contrib>Chapter on Keyboard Events.</contrib>
      </author>
      <author lang="en">
        <firstname>Kjell</firstname>
        <surname>Ahlstedt</surname>
        <contrib>Parts of the update from gtkmm 2 to gtkmm 3.</contrib>
        <contrib>Chapter on "Building applications".</contrib>
      </author>
    </authorgroup>

    <abstract>

      <!-- This text is copied from the introduction. -->
      <para>Cet ouvrage explicite les concepts-clés de l'API C++ <application>gtkmm</application> pour la création d'interfaces utilisateur. Il présente également les principaux éléments graphiques d'interfaçage utilisateur (« widgets » en anglais, « contrôles » ou « éléments graphiques » en français).</para>

    </abstract>

    <copyright lang="en">
      <year>2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010</year>
      <holder>Murray Cumming</holder>
    </copyright>

    <legalnotice>
      <para>Permission vous est donnée de copier, distribuer et/ou modifier ce document selon les termes de la licence de documentation libre GNU, Version 1.2 ou ultérieure publiée par la Free Software Foundation sans section inaltérable, sans texte de première page de couverture ni texte de dernière page de couverture. Vous pouvez obtenir un exemplaire de cette licence en visitant le site Web de cette organisation ou en écrivant à : Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.</para>
    </legalnotice>

  </bookinfo>

<chapter id="chapter-introduction">
<title>Introduction</title>

<sect1 id="sec-this-book">
<title>Cet ouvrage</title>

<para>Cet ouvrage explicite les concepts-clés de l'API C++ <application>gtkmm</application> pour la création d'interfaces utilisateur. Il présente également les principaux éléments graphiques de l'interfaçage utilisateur (« widgets » en anglais, « contrôles » ou « éléments graphiques » en français). Même s'il est fait mention de classes, de constructeurs et de fonctions membres, ces concepts ne sont pas examinés en détail. Par conséquent, pour une information complète sur l'API, il conviendra de vous reporter à la documentation de référence.</para>

<para>Cet ouvrage suppose une bonne connaissance du C++, ainsi que des méthodes de création de programmes avec ce langage.</para>

<para>Nous souhaitons vivement que vous nous rapportiez tout problème rencontré dans l'apprentissage de <application>gtkmm</application> avec ce document ; cela nous permet d'y apporter des améliorations en conséquence. Veuillez vous reporter au chapitre <link linkend="chapter-contributing">Contribution</link> pour plus d'informations.</para>
</sect1>

<sect1 id="sec-gtkmm">
<title>gtkmm</title>
<para><application>gtkmm</application> est un habillage (« wrapper ») C++ pour <ulink url="http://www.gtk.org/">GTK+</ulink>, une bibliothèque servant elle-même à créer des interfaces utilisateur graphique. <application>gtkmm</application> est sous licence LGPL : vous pouvez donc développer des logiciels ouverts, des logiciels libres ou même des logiciels commerciaux non-libres sans acheter de licence.</para>
<para>À l'origine <application>gtkmm</application> s'appelait « gtk-- » étant donné que GTK+ avait déjà un signe « + » dans le nom. Mais, comme « -- » n'est pas facilement indexé par les moteurs de recherche, le paquet logiciel a couramment été désigné par <application>gtkmm</application> et c'est ainsi que nous le désignerons dans la suite.</para>

<sect2 id="why-use-gtkmm">
<title>Pourquoi utiliser <application>gtkmm</application> plutôt que GTK+ ?</title>
<para><application>gtkmm</application> vous permet d'écrire du code en se servant des techniques habituelles du C++ telles que l'encapsulation, la dérivation et le polymorphisme. En tant que programmeur C++, vous avez probablement déjà perçu que ces possibilités conduisent à un code plus clair et mieux organisé.</para>
<para><application>gtkmm</application> possède une sécurité améliorée pour la typologie des données ; le compilateur détecte donc des erreurs qui ne seraient apparues qu'au moment de l'exécution en C. L'utilisation de ces types spécifiques rend l'API plus claire puisque vous pouvez voir les types à utiliser à la simple lecture de la déclaration d'une fonction membre.</para>
<para>L'héritage s'utilise pour dériver de nouveaux éléments graphiques. Dans un code C de GTK+, ce processus de dérivation est si complexe et sujet à erreur que quasiment aucun programmeur C ne l'utilise. En tant que développeur C++, vous savez que la dérivation est une technique essentielle dans la programmation orientée objet.</para>
<para>L'utilisation des instances membres simplifie la gestion de la mémoire. Tous les éléments graphiques C de GTK+ sont traités en utilisant des pointeurs. Vous savez, comme tout programmeur C++, que les pointeurs doivent, si possible, être évités.</para>
<para>Comparé à GTK+, avec l'utilisation des noms de fonctions préfixés et de nombreuses macros de forçage de type, <application>gtkmm</application> nécessite moins de code.</para>
</sect2>

<sect2 id="gtkmm-vs-qt">
<title><application>gtkmm</application> comparée à <application>Qt</application></title>
<para>Qt de Trolltech est le plus proche concurrent de <application>gtkmm</application> ; cela mérite une explication.</para>

<para lang="en"><application>gtkmm</application> developers tend to prefer <application>gtkmm</application> to Qt because <application>gtkmm</application> does things in a more C++ way. Qt originates from a time when C++ and the standard library were not standardised or well supported by compilers. It therefore duplicates a lot of stuff that is now in the standard library, such as containers and type information. Most significantly, Trolltech modified the C++ language to provide signals, so that Qt classes cannot be used easily with non-Qt classes. <application>gtkmm</application> was able to use standard C++ to provide signals without changing the C++ language.
See the <ulink url="https://wiki.gnome.org/Projects/gtkmm/FAQ">FAQ</ulink> for more detailed differences.</para>
</sect2>

<sect2 id="gtkmm-is-a-wrapper">
<title><application>gtkmm</application> est un habillage</title>
<para><application>gtkmm</application> n'est pas une boîte à outils en C++ natif, mais un habillage C++ d'une boîte à outils en C. Cette séparation entre interface et implémentation a des avantages. Les développeurs <application>gtkmm</application> passent la majeure partie de leur temps à discuter de la manière dont <application>gtkmm</application> peut présenter l'API la plus claire, sans compromis délicat en raison d'obscurs détails techniques. Nous contribuons un peu aux fondements du code GTK+ sous-jacent, mais les codeurs en C, Perl et Python, etc. font de même. Ainsi GTK+ bénéficie d'une base d'utilisateurs plus large que n'aurait une boîte à outils spécifique à un langage — il y a plus d'implémentations, plus de développeurs, plus de testeurs et plus d'utilisateurs.</para>
</sect2>
</sect1>

</chapter>

<chapter id="chapter-installation">
<title>Installation</title>
<sect1 id="sec-installation-dependencies">
<title>Dépendances</title>
<para lang="en">
  Before attempting to install <application>gtkmm</application> 3.0, you might first need to install these other
  packages.
</para>
<itemizedlist>
  <listitem><para lang="en"><application>libsigc++ 2.0</application></para></listitem>
  <listitem><para lang="en"><application>GTK+ 3.0</application></para></listitem>
  <listitem><para lang="en"><application>glibmm</application></para></listitem>
  <listitem><para lang="en"><application>cairomm</application></para></listitem>
  <listitem><para lang="en"><application>pangomm</application></para></listitem>
  <listitem><para lang="en"><application>atkmm</application></para></listitem>
</itemizedlist>
<para>Ces dépendances ont elles-mêmes leurs propres dépendances, comprenant les applications et bibliothèques suivantes :</para>
<itemizedlist>
  <listitem><para lang="en"><application>pkg-config</application></para></listitem>
  <listitem><para lang="en"><application>glib</application></para></listitem>
  <listitem><para lang="en"><application>ATK</application></para></listitem>
  <listitem><para lang="en"><application>Pango</application></para></listitem>
  <listitem><para lang="en"><application>cairo</application></para></listitem>
  <listitem><para lang="en"><application>gdk-pixbuf</application></para></listitem>
</itemizedlist>
</sect1>

<sect1 id="sec-install-unix-and-linux">
<title>Unix et Linux</title>

<sect2 id="sec-linux-install-from-packages">
<title>Paquets logiciels pré-compilés</title>

<para>Les versions récentes de <application>gtkmm</application> sont empaquetées par pratiquement toutes les grandes distributions Linux. Donc, si vous êtes un utilisateur de Linux, vous pourrez probablement débuter avec <application>gtkmm</application> en installant son paquet à partir du dépôt officiel de votre distribution. Parmi les distributions qui mettent à disposition <application>gtkmm</application> dans leurs dépôts, citons Debian, Ubuntu, Red Hat, Fedora, Mandriva, Suse, mais il y en a beaucoup d'autres.</para>
<para lang="en">
    The names of the <application>gtkmm</application> packages vary from distribution to distribution
    (e.g. <application>libgtkmm-3.0-dev</application> on Debian and Ubuntu or
    <application>gtkmm30-devel</application> on Red Hat Fedora), so check with
    your distribution's package management program for the correct package name
    and install it like you would any other package.
</para>
<note>
<para lang="en">
The package names will not change when new API/ABI-compatible versions of <application>gtkmm</application>
are released. Otherwise they would not be API/ABI-compatible. So don't be
surprised, for instance, to find <application>gtkmm</application> 3.8 supplied by Debian's
<application>libgtkmm-3.0-dev</application> package.
</para>
</note>
</sect2>

<sect2 id="sec-install-from-source">
<title>Installation à partir des sources</title>

<para>Si votre distribution ne met pas à disposition un paquet pré-compilé de <application>gtkmm</application>, ou bien si vous souhaitez installer une version différente de celle fournie, vous pouvez installer <application>gtkmm</application> à partir des sources. Le code source de <application>gtkmm</application> est téléchargeable à partir de <ulink url="http://www.gtkmm.org/"/>.</para>
<para>Après installation de toutes les dépendances, téléchargez le code source de <application>gtkmm</application>, extrayez-le et déplacez vous dans le nouveau répertoire. <application>gtkmm</application> se construit et s'installe en saisissant cette suite de commandes :</para>
<screen>
# ./configure
# make
# make install
</screen>
<note>
<para lang="en">
  Remember that on a Unix or Linux operating system, you will probably need to
  be <literal>root</literal> to install software. The <command>su</command> or <command>sudo</command>
  command will allow you to enter the <literal>root</literal> password and have
  <literal>root</literal> status temporarily.
</para>
</note>
<para>Le script <filename>configure</filename> effectue une vérification pour s'assurer que toutes les dépendances requises sont déjà installées. Si une quelconque manque, il s'arrête et affiche une erreur.</para>
<para lang="en">
    By default, <application>gtkmm</application> will be installed under the
    <filename>/usr/local</filename> directory. On some systems you may need to
    install to a different location. For instance, on Red Hat Linux systems
    you might use the <literal>--prefix</literal> option with configure, like
    so:
<screen lang="en">
# ./configure --prefix=/usr
</screen>
</para>
<warning>
    <para>Il faut être très précautionneux si vous faites une installation avec comme préfixe un des répertoires système standard, comme <filename>/usr</filename>. Les distributions Linux installent leurs paquets logiciels dans <filename>/usr</filename> ; donc, le fait d'installer un paquet source dans ce répertoire peut corrompre ou entrer en conflit avec un logiciel installé par le système de gestion des paquets de votre distribution. Dans un monde idéal, vous devriez utiliser un préfixe à part pour tous les logiciels installés à partir des sources.</para>
</warning>
<para>Si vous souhaitez participer au développement de <application>gtkmm</application> ou expérimenter de nouvelles fonctionnalités, vous pouvez installer <application>gtkmm</application> à partir du dépôt « git ». La plupart des utilisateurs n'ont jamais besoin de faire ainsi, mais si vous êtes intéressé par une participation au développement de <application>gtkmm</application>, consultez l'annexe <link linkend="chapter-working-with-source">Travail sur le code source de gtkmm</link></para>
</sect2>

</sect1>

<sect1 id="sec-packages-windows">
<title>Windows Microsoft</title>
<para lang="en">GTK+ and <application>gtkmm</application> were designed to work well with Microsoft Windows, and the developers encourage its use on the win32 platform. However, Windows has no standard installation system for development libraries. Please see the <ulink url="https://wiki.gnome.org/Projects/gtkmm/MSWindows">Windows Installation</ulink>
page for Windows-specific installation instructions and notes.</para>
</sect1>

</chapter>

<chapter id="chapter-basics">
<title>Fondamentaux</title>

<para>Ce chapitre présente quelques aspects parmi les plus importants du codage avec <application>gtkmm</application>. Nous les montrerons à partir d'exemples simples et fonctionnels de code. Ce n'est toutefois qu'un avant-goût et vous aurez besoin d'examiner les autres chapitres pour des informations plus conséquentes.</para>
<para>Vos connaissances en matière de C++ vous seront d'un bon secours pour <application>gtkmm</application> comme pour toute autre bibliothèque. À moins que nous n'indiquions le contraire, vous pouvez vous attendre à ce que les classes <application>gtkmm</application> aient un comportement identique à celui des autres classes C++ et donc à utiliser vos techniques C++ habituelles avec elles.</para>

<sect1 id="sec-basics-simple-example">
<title>Un exemple simple</title>

<para>Comme entrée en matière avec <application>gtkmm</application>, nous débuterons avec le programme le plus simple qui soit. Ce programme crée une fenêtre vide de 200 x 200 pixels.</para>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/base?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>base.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include &lt;gtkmm.h&gt;

int main(int argc, char *argv[])
{
  auto app =
    Gtk::Application::create(argc, argv,
      "org.gtkmm.examples.base");

  Gtk::Window window;
  window.set_default_size(200, 200);

  return app-&gt;run(window);
}
</programlisting>
<!-- end inserted example code -->

<para>Détaillons maintenant chaque ligne de l'exemple</para>
<programlisting>#include &lt;gtkmm.h&gt;</programlisting>
<para>Tous les programmes <application>gtkmm</application> doivent inclure certains fichiers d'en-tête <application>gtkmm</application> ; <literal>gtkmm.h</literal> inclut la totalité du jeu d'en-têtes <application>gtkmm</application>. En règle générale, ce n'est pas une bonne idée parce que cette façon de faire inclut à peu près un mégaoctet d'en-têtes, mais pour des programmes simples, c'est acceptable.</para>

<para lang="en">
The next statement:

<programlisting lang="en">Glib::RefPtr&lt;Gtk::Application&gt; app = Gtk::Application::create(argc, argv, "org.gtkmm.examples.base");</programlisting>

creates a <classname>Gtk::Application</classname> object, stored in a <classname>RefPtr</classname> smartpointer. This is needed in all <application>gtkmm</application>
applications. The <methodname>create()</methodname> method for this object initializes <application>gtkmm</application>, and checks the
arguments passed to your application on the command line, looking for
standard options such as <literal>--display</literal>. It takes these from the argument list, leaving anything it does not
recognize for your application to parse or ignore. This ensures
that all <application>gtkmm</application> applications accept the same set of standard arguments.
</para>

<para lang="en">
The next two lines of code create a window and set its default (initial) size:
</para>
<programlisting lang="en">Gtk::Window window;
window.set_default_size(200, 200);</programlisting>
<para lang="en">
The last line shows the window and enters the <application>gtkmm</application> main processing loop, which will finish when the window is closed.
Your <function>main()</function> function will then return with an appropriate success or error code.
</para>

<programlisting lang="en">return app-&gt;run(window);</programlisting>

<para lang="en">
After putting the source code in <literal>simple.cc</literal> you can compile
the above program with <application>gcc</application> using:
<programlisting lang="en">g++ simple.cc -o simple `pkg-config gtkmm-3.0 --cflags --libs`</programlisting>
Note that you must surround the <literal>pkg-config</literal> invocation with backquotes.
Backquotes cause the shell to execute the command inside them, and to use
the command's output as part of the command line.
Note also that <literal>simple.cc</literal> must come before the <literal>pkg-config</literal>
invocation on the command line.
</para>
</sect1>

<sect1 id="sec-headers-and-linking">
<title>Fichiers d'en-têtes et édition des liens </title>
<para lang="en">
Although we have shown the compilation command for the simple example, you really should use the automake and autoconf tools, as described in "Autoconf, Automake, Libtool", by G. V. Vaughan et al. The examples used in this book are included in the <application>gtkmm-documentation</application> package, with appropriate build files, so we won't show the build commands in future. You'll just need to find the appropriate directory and type <literal>make</literal>.
</para>
<para>Pour simplifier la compilation, nous utilisons <literal>pkg-config</literal>, présent dans toutes les installations de <application>gtkmm</application> (correctement effectuées). Ce programme « sait » quels sont les commutateurs nécessaires à la compilation des programmes utilisant <application>gtkmm</application>. L'option <literal>--cflags</literal> demande à <literal>pkg-config</literal> de produire la liste des répertoires des en-têtes, répertoires que le compilateur devra parcourir ; l'option <literal>--libs</literal> demande la liste des bibliothèques nécessaires à l'édition des liens par le compilateur ainsi que les répertoires où elles se trouvent. Essayez de lancer directement cette commande à l'invite de votre terminal pour voir les résultats sur votre système.</para>
<para lang="en">
However, this is even simpler when using the <function>PKG_CHECK_MODULES()</function> macro in a standard configure.ac file with autoconf and automake.
For instance:
<programlisting lang="en">PKG_CHECK_MODULES([MYAPP], [gtkmm-3.0 &gt;= 3.8.0])</programlisting>
This checks for the presence of gtkmm and defines MYAPP_LIBS and MYAPP_CFLAGS for use in your Makefile.am files.
</para>
<para lang="en">gtkmm-3.0 is the name of the current stable API. There was an older API called gtkmm-2-4 which installs in parallel when it is available. There were several versions of gtkmm-2.4, such as gtkmm 2.10 and there are several versions of the gtkmm-3.0 API. Note that the API name does not change for every version because that would be an incompatible API and ABI break. Theoretically, there might be a future gtkmm-4.0 API which would install in parallel with gtkmm-3.0 without affecting existing applications.
</para>

<para lang="en">Note that if you mention extra modules in addition to gtkmm-3.0, they should be separated by spaces, not commas.
</para>
<para>Openismus fournit une <ulink url="http://www.openismus.com/documents/linux/automake/automake.shtml">Aide sur les fondamentaux avec automake et autoconf</ulink>.</para>

</sect1>

<sect1 id="sec-widgets-overview">
<title>Éléments graphiques</title>
<para>Les applications <application>gtkmm</application> sont constituées par des fenêtres comportant des éléments graphiques, comme des boutons ou des boîtes de texte. Dans certains autres systèmes, les éléments graphiques sont appelés « contrôles ». Pour chaque élément graphique dans les fenêtres d'une application, il existe un objet C++ dans le code de l'application. Il vous suffit donc d'appeler une fonction membre de la classe de l'élément graphique pour en modifier l'apparence.</para>
 <para lang="en">Widgets are arranged inside container widgets such as frames and notebooks, in a hierarchy of widgets within widgets. Some of these container widgets, such as <classname>Gtk::Grid</classname>, are not visible - they exist only to arrange other widgets. Here is some example code that adds 2 <classname>Gtk::Button</classname> widgets to a <classname>Gtk::Box</classname> container widget:
<programlisting lang="en">m_box.pack_start(m_Button1);
m_box.pack_start(m_Button2);</programlisting>
and here is how to add the <classname>Gtk::Box</classname>, containing those buttons, to a <classname>Gtk::Frame</classname>, which has a visible frame and title:
<programlisting lang="en">m_frame.add(m_box);</programlisting>
</para>
<para>La plupart des chapitres de cet ouvrage traitent d'éléments graphiques spécifiques. Consultez la section <link linkend="chapter-container-widgets">Éléments graphiques conteneurs</link> pour de plus amples précisions sur la manière de placer des éléments graphiques dans des conteneurs.</para>

<para>Même s'il est possible de préciser la disposition et l'apparence des fenêtres ainsi que des éléments graphiques dans le code C++, vous trouverez certainement plus pratique de concevoir vos interfaces utilisateur avec <literal>Glade</literal> et de les charger avec <literal>Gtk::Builder</literal> à l'exécution de l'application. Consultez le chapitre <link linkend="chapter-builder">Glade et Gtk::Builder</link>.</para>

<para>Même si les instances d'éléments graphiques <application>gtkmm</application> ont des durées de vie et des portées comme toute autre classe C++, <application>gtkmm</application> dispose d'une fonctionnalité optionnelle que vous pourrez observer dans certains exemples ; elle permet de gagner du temps. <function>Gtk::manage()</function> vous permet d'indiquer qu'un élément graphique enfant est détenu par le conteneur dans lequel vous le placez. Cela permet de créer l'élément graphique avec <function>new</function>, l'ajouter au conteneur et ne pas vous préoccuper de sa destruction. Vous en apprendrez plus au sujet des techniques de gestion de la mémoire dans <application>gtkmm</application> dans le chapitre <link linkend="chapter-memory">Gestion de la mémoire</link>.</para>

</sect1>

<sect1 id="sec-signals-overview">
<title>Signaux</title>

<para><application>gtkmm</application>, comme la plupart des boîtes à outils GUI, est <emphasis>piloté par événements</emphasis>. Lorsqu'un événement survient, comme un clic de bouton de souris, le signal approprié est <emphasis>émis</emphasis> par l'élément graphique pointé. Chaque élément graphique dispose d'un jeu de signaux à émettre. Pour qu'un clic de bouton se traduise par une action, nous mettons en œuvre un <emphasis>gestionnaire de signal</emphasis> pour capturer le signal « clicked » du bouton.</para>
<para lang="en"><application>gtkmm</application> uses the libsigc++ library to implement signals. Here is an example line of code that connects a Gtk::Button's "clicked" signal with a signal handler called "on_button_clicked":
<programlisting lang="en">m_button1.signal_clicked().connect( sigc::mem_fun(*this,
  &amp;HelloWorld::on_button_clicked) );</programlisting>
</para>

<para>Pour plus de détails à propos des signaux, consultez cette <link linkend="chapter-signals">annexe</link>.</para>
<para>Pour des informations sur l'implémentation de vos propres signaux au lieu d'une simple connexion aux signaux prédéfinis de <application>gtkmm</application>, consultez cette <link linkend="chapter-custom-signals">annexe</link>.</para>

</sect1>

<sect1 id="sec-basics-ustring">
<title>Glib::ustring</title>
<para lang="en">You might be surprised to learn that <application>gtkmm</application> doesn't use <classname>std::string</classname> in its interfaces. Instead it uses <classname>Glib::ustring</classname>, which is so similar and unobtrusive that you could actually pretend that each <classname>Glib::ustring</classname> is a <classname>std::string</classname> and ignore the rest of this section. But read on if you want to use languages other than English in your application.</para>
<para lang="en">std::string uses 8 bit per character, but 8 bits aren't enough to encode languages such as Arabic, Chinese, and Japanese. Although the encodings for these languages have now been specified by the Unicode Consortium, the C and C++ languages do not yet provide any standardised Unicode support. GTK+ and GNOME chose to implement Unicode using UTF-8, and that's what is wrapped by Glib::ustring. It provides almost exactly the same interface as std::string, along with automatic conversions to and from std::string.</para>
<para>Un des avantages de UTF-8 est que son utilisation n'est pas obligatoire, sauf à le vouloir ; vous n'avez pas besoin de retoucher tout votre code sur le champ. <classname>std::string</classname> fonctionne toujours bien avec les chaînes ASCII 7 bits. Mais si vous essayez de régionaliser vos applications pour des langues comme le chinois, par exemple, vous constaterez des erreurs étranges, voire des blocages. Alors, il ne vous reste plus qu'à utiliser dès maintenant <classname>Glib::ustring</classname> à la place.</para>
<para>Notez que UTF-8 n'est pas compatible avec des encodages 8 bits comme ISO-8859-1. Par exemple, les trémas de l'allemand ne font pas partie de la gamme des caractères ASCII ; ils nécessitent plus d'un octet en UTF-8. Si votre code comporte des chaînes littérales sur 8 bits, vous devez les convertir en UTF-8 (par exemple, la formule de salut bavaroise « Grüß Gott » devient « Gr\xC3\xBC\xC3\x9F Gott »).</para>
<para>Vous devez éviter les arithmétiques de pointeurs dans le style du C et les fonctions comme strlen(). En UTF-8, chaque caractère peut nécessiter de 1 à 6 octets ; il n'est donc pas possible de présupposer que l'octet suivant est un nouveau caractère. <classname>Glib::ustring</classname> se préoccupe de ces détails à votre place ; vous pouvez employer des fonctions membres telles que Glib::ustring::substr() en pensant caractères et non octets.</para>

<para>Contrairement à la solution de l'Unicode UCS-2 de Windows, UTF-8 ne requiert aucune option spéciale de compilation pour le traitement des chaînes de caractères ; en conséquence, il n'existe pas de bibliothèque ou d'exécutable Unicode incompatible avec ceux en ASCII.</para>

<para lang="en"><ulink url="http://developer.gnome.org/glibmm/2.50/classGlib_1_1ustring.html">Reference</ulink></para>

<para>Consultez le chapitre sur l'<link linkend="chapter-internationalization">Internationalisation</link> pour des informations concernant les chaînes littérales UTF-8.</para>

</sect1>

<sect1 id="sec-intermediate-types">
<title>Types intermédiaires</title>
<para lang="en">Some API related to gtkmm uses intermediate data containers, such as <classname>Glib::StringArrayHandle</classname>, instead of a specific Standard C++ container such as <classname>std::vector</classname> or <classname>std::list</classname>, though <application>gtkmm</application> itself now uses just <classname>std::vector</classname> since <application>gtkmm</application> 3.0.</para>
<para lang="en">You should not declare these types yourself. You should instead use whatever Standard C++ container you prefer. glibmm will do the conversion for you. Here are some of these intermediate types:
<itemizedlist>
    <listitem><para lang="en"><classname>Glib::StringArrayHandle</classname> or <classname>Glib::ArrayHandle&lt;Glib::ustring&gt;</classname>: Use <classname>std::vector&lt;Glib::ustring&gt;</classname>, <classname>std::list&lt;Glib::ustring&gt;</classname>, <type>const char*[]</type>, etc.</para></listitem>
    <listitem><para lang="en"><classname>Glib::ListHandle&lt;Gtk::Widget*&gt;</classname>: Use <classname>std::vector&lt;Gtk::Widget*&gt;</classname>, <classname>std::list&lt;Gtk::Widget*&gt;</classname>, etc.</para></listitem>
    <listitem><para lang="en"><classname>Glib::SListHandle&lt;Gtk::Widget*&gt;</classname>: Use <classname>std::vector&lt;Gtk::Widget*&gt;</classname>, <classname>std::list&lt;Gtk::Widget*&gt;</classname>, etc.</para></listitem>
</itemizedlist>

</para>

</sect1>

<sect1 id="sec-basics-gobj-and-wrap">
<title>Mélange des API C et C++</title>
<para>Vous pouvez utiliser des API C, si elles n'ont pas encore d'interfaces C++ commodes. Il n'y a généralement aucun problème avec l'utilisation des API C dans le C++ ; <application>gtkmm</application> vous aide en donnant un accès à l'objet C sous-jacent et en facilitant la création d'un objet C++ enveloppe de l'objet C, à condition que l'API C soit également fondée sur le système GObject.</para>

<para>Pour utiliser un élément <application>gtkmm</application> avec une fonction C demandant un type d'objet GObject C, servez-vous de la fonction <function>gobj()</function> pour obtenir un pointeur sur l'instance du GObject sous-jacent. Par exemple</para>

<para>
<programlisting>
Gtk::Button* button = new Gtk::Button("exemple");
gtk_button_do_something_new(button-&gt;gobj());
</programlisting>
</para>

<para>Pour obtenir un objet <application>gtkmm</application> à partir d'un élément GObject C, utilisez la fonction  Glib::wrap(). Par exemple</para>
<para>
<programlisting>
GtkButton* cbutton = get_a_button();
Gtk::Button* button = Glib::wrap(cbutton);
</programlisting>
</para>
</sect1>

<sect1 id="sec-helloworld">
<title>Hello World en <application>gtkmm</application></title>

<para>Nous en savons maintenant assez pour examiner un exemple réel. Pour reprendre une vieille tradition du monde de l'informatique, nous allons maintenant présenter le programme « Hello World » accommodé à la <application>gtkmm</application> :</para>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/helloworld?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>helloworld.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLE_HELLOWORLD_H
#define GTKMM_EXAMPLE_HELLOWORLD_H

#include &lt;gtkmm/button.h&gt;
#include &lt;gtkmm/window.h&gt;

class HelloWorld : public Gtk::Window
{

public:
  HelloWorld();
  virtual ~HelloWorld();

protected:
  //Signal handlers:
  void on_button_clicked();

  //Member widgets:
  Gtk::Button m_button;
};

#endif // GTKMM_EXAMPLE_HELLOWORLD_H
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "helloworld.h"
#include &lt;gtkmm/application.h&gt;

int main (int argc, char *argv[])
{
  auto app = Gtk::Application::create(argc, argv, "org.gtkmm.example");

  HelloWorld helloworld;

  //Shows the window and returns when it is closed.
  return app-&gt;run(helloworld);
}
</programlisting>
<para lang="en">File: <filename>helloworld.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "helloworld.h"
#include &lt;iostream&gt;

HelloWorld::HelloWorld()
: m_button("Hello World")   // creates a new button with label "Hello World".
{
  // Sets the border width of the window.
  set_border_width(10);

  // When the button receives the "clicked" signal, it will call the
  // on_button_clicked() method defined below.
  m_button.signal_clicked().connect(sigc::mem_fun(*this,
              &amp;HelloWorld::on_button_clicked));

  // This packs the button into the Window (a container).
  add(m_button);

  // The final step is to display this newly created widget...
  m_button.show();
}

HelloWorld::~HelloWorld()
{
}

void HelloWorld::on_button_clicked()
{
  std::cout &lt;&lt; "Hello World" &lt;&lt; std::endl;
}
</programlisting>
<!-- end inserted example code -->

<para>Essayez de le compiler et de le lancer avant de poursuivre. Vous devriez voir quelque chose comme :</para>

<figure id="figure-helloworld">
  <title>Hello World</title>
  <screenshot>
    <graphic format="PNG" fileref="figures/helloworld.png"/>
  </screenshot>
</figure>

<para>Tout à fait palpitant, n'est-ce-pas ? Examinons le code. D'abord, la classe <classname>HelloWorld</classname> :</para>

<programlisting>class HelloWorld : public Gtk::Window
{

public:
  HelloWorld();
  virtual ~HelloWorld();

protected:
  //Gestionnaire de signal :
  virtual void on_button_clicked();

  //éléments graphiques membres :
  Gtk::Button m_button;
};</programlisting>

<para>Cette classe implémente la fenêtre « Hello World ». Elle est dérivée de la classe <classname>Gtk::Window</classname> et possède un simple <classname>Gtk::Button</classname> comme membre. Nous avons pris le parti d'utiliser le constructeur pour faire toutes les tâches d'initialisation de la fenêtre, y compris la définition des signaux. Voici le code, les commentaires sont omis :</para>

<programlisting>HelloWorld::HelloWorld()
:
  m_button ("Hello World")
{
  set_border_width(10);
  m_button.signal_clicked().connect(sigc::mem_fun(*this,
    &amp;HelloWorld::on_button_clicked));
  add(m_button);.
  m_button.show();
}</programlisting>

<para>Notez que nous avons utilisé une instruction d'initialisation pour étiqueter l'objet <literal>m_button</literal> avec « Hello World ».</para>

<para>Puis nous appelons la fonction membre <methodname>set_border_width()</methodname> de l'objet Window. Elle fixe la dimension de l'espace entre les côtés de la fenêtre et l'élément graphique qu'elle contient.</para>

<para>Ensuite, nous raccordons un gestionnaire de signal pour le signal <literal>clicked</literal> du <literal>m_button</literal>. Le gestionnaire affiche sur <literal>stdout</literal> notre salut amical.</para>

<para>Puis, nous utilisons la fonction membre <methodname>add()</methodname> avec l'objet Window pour y placer le <literal>m_button</literal> (<methodname>add()</methodname> est une fonction membre de la classe <classname>Gtk::Container</classname> que nous décrirons dans le chapitre des éléments graphiques conteneurs). La fonction <methodname>add()</methodname> place l'élément graphique dans la fenêtre, mais elle ne l'affiche pas. Les éléments graphiques <application>gtkmm</application> sont toujours invisibles à leur création — pour les afficher, vous devez faire appel à la fonction <methodname>show()</methodname>, ce que nous faisons à la ligne suivante.</para>


<para>Maintenant examinons la fonction <function>main()</function> du programme. La voici, sans commentaire :</para>

<programlisting lang="en">int main(int argc, char** argv)
{
  Glib::RefPtr&lt;Gtk::Application&gt; app = Gtk::Application::create(argc, argv, "org.gtkmm.example");

  HelloWorld helloworld;
  return app-&gt;run(helloworld);
}</programlisting>

<para lang="en">
First we instantiate an object stored in a <classname>RefPtr</classname> smartpointer called <literal>app</literal>. This is of type
<classname>Gtk::Application</classname>. Every <application>gtkmm</application> program must have one of these. We pass
our command-line arguments to its create() method. It takes the arguments
it wants, and leaves you the rest, as we described earlier.
</para>

<para lang="en">
Next we make an object of our <classname>HelloWorld</classname> class, whose constructor
takes no arguments, but it isn't visible yet. When we call <methodname>Gtk::Application::run()</methodname>, giving it the helloworld Window, it shows the Window and starts the <application>gtkmm</application> <emphasis>event loop</emphasis>. During the event loop <application>gtkmm</application> idles, waiting for actions from the user, and responding appropriately. When the user closes the Window, run() will return, causing the final line of our main() function be to executed. The application will then finish.
</para>

</sect1>
</chapter>

<chapter id="changes-gtkmm3">
<title lang="en">Changes in <application>gtkmm</application> 3</title>

<para lang="en"><application>gtkmm</application>-3.0 is a new version of the <application>gtkmm</application> API that installs in parallel with the older <application>gtkmm</application>-2.4 API. The last version of the <application>gtkmm</application>-2.4 API was <application>gtkmm</application> 2.24. <application>gtkmm</application> 3 has no major fundamental differences to <application>gtkmm</application> 2 but does make several small changes that were not possible while maintaining binary compatibility. If you never used the <application>gtkmm</application>-2.4 API then you can safely ignore this chapter.</para>

<para lang="en"><application>gtkmm</application> 3's library is called <literal>libgtkmm-3.0</literal> rather than <literal>libgtkmm-2.4</literal> and installs its headers in a similarly-versioned directory, so your pkg-config check should ask for <literal>gtkmm-3.0</literal>  rather than <literal>gtkmm-2.4</literal>.</para>


<para lang="en"><application>gtkmm</application> 3 added some new classes:</para>

<orderedlist>
<listitem><simpara lang="en"><classname>Gtk::AppChooser</classname>, <classname>Gtk::AppChooserButton</classname>, <classname>Gtk::AppChooserDialog</classname> allow the user to select an installed application to open a particular type of content.</simpara></listitem>
<listitem><simpara lang="en"><classname>Gtk::Grid</classname> is a new container widget that will eventually replace <classname>Gtk::Box</classname> and <classname>Gtk::Table</classname>. It arranges its children according to properties of those children rather than its own layout details.</simpara></listitem>
<listitem><simpara lang="en"><classname>Gtk::Switch</classname> displays On/Off states more explictly than <classname>Gtk::CheckBox</classname>. It may be useful, for instance, when allowing users to activate hardware.</simpara></listitem>
</orderedlist>

<para lang="en"><application>gtkmm</application> 3 also made several small changes to the API, which you will probably encounter when porting code that used <application>gtkmm</application>-2.4. Here is a short list:</para>

<para>
<orderedlist>

<listitem><simpara lang="en"><classname>Gtk::CellLayout</classname>, used by <classname>Gtk::IconView</classname>, <classname>Gtk::TreeView::Column</classname> and <classname>Gtk::ComboBox</classname>, now has a <classname>Gtk::CellArea</classname> which can be used to specify more details of how the <classname>CellRenderer</classname>s are arranged and aligned.</simpara></listitem>

<listitem><simpara lang="en">Gtk::ComboBox now derives from CellLayout, allowing easier layout and alignment of its <classname>Gtk::CellRenderer</classname>s.</simpara></listitem>

<listitem><simpara lang="en"><classname>Gtk::Adjustment</classname> and <classname>IconSet</classname> and <classname>Gdk::Cursor</classname> are now used via <classname>Glib::RefPtr</classname>.</simpara></listitem>

<listitem><simpara lang="en"><classname>Gtk::Box</classname>, <classname>Gtk::ButtonBox</classname>, <classname>Gtk::IconView</classname>, <classname>Gtk::Paned</classname>, <classname>Gtk::ProgressBar</classname>, <classname>Gtk::ScaleButton</classname>, <classname>Gtk::Scrollbar</classname> and <classname>Gtk::Separator</classname> now derive from <classname>Gtk::Orientable</classname>, allowing their
orientation (vertical or horizontal) to be specified without requiring the use of a derived class such as <classname>Gtk::HBox</classname>.</simpara></listitem>

<listitem><simpara lang="en"><classname>Gtk::IconView</classname>, <classname>Gtk::TextView</classname>, <classname>Gtk::TreeView</classname> and other widgets derive from Scrollable instead of having their own methods such as <methodname>get_vadjustment()</methodname> and instead of having their own set_scroll_adjustments signal.</simpara></listitem>

<listitem><simpara lang="en"><classname>Gtk::Style</classname> and <classname>Gtk::Rc</classname> were removed, replaced by <classname>Gtk::StyleContext</classname>, and <classname>Gtk::StyleProvider</classname>s, such as <classname>Gtk::CssProvider</classname>.</simpara></listitem>

<listitem><simpara lang="en">Widget::on_expose_event() was replaced by Widget::on_draw(), which assumes that cairomm is used for drawing, via the provided <classname>Cairo::Context</classname> and does not require you to call <methodname>Cairo::Context::clip()</methodname>.</simpara></listitem>

<listitem><simpara lang="en"><classname>Gdk::RGBA</classname> replaces <classname>Color</classname>, adding an alpha component for opacity. <classname>Colormap</classname> was removed, along with its awkward use to allocate colors.</simpara></listitem>

<listitem><simpara lang="en"><classname>Gdk::Pixmap</classname> and <classname>Gdk::Bitmap</classname> were removed in favour of <classname>Gdk::Pixbuf</classname>.</simpara></listitem>

<listitem><simpara lang="en"><classname>Gdk::Drawable</classname> was removed, with its methods moving into <classname>Gdk::Window</classname>.</simpara></listitem>

<listitem><simpara lang="en">We now use std::vector in several methods instead of the intermediate *Handle types to make the API clearer.</simpara></listitem>

</orderedlist>
</para>

<para lang="en">All deprecated API was removed in <application>gtkmm</application> 3.0, though there will be new deprecations in future versions.</para>

<para lang="en">As a first step to porting your source code to <application>gtkmm</application>-3.0 you should probably ensure that your application builds with the deprecated <application>gtkmm</application>-2.4 API disabled, by defining macro such as GTKMM_DISABLE_DEPRECATED. There are some autotools macros that can help with this by defining them optionally at build time. See the <ulink url="https://wiki.gnome.org/Projects/gtkmm/PortingToGtkmm3">gtkmm 3 porting wiki page</ulink> for more details.</para>

</chapter>

<chapter id="chapter-button-widget">
<title>Boutons</title>

<para><application>gtkmm</application> met à votre disposition quatre types basiques de boutons :</para>

<variablelist>

<varlistentry>
<term>Bouton poussoir</term>
<listitem>
<para lang="en">
<ulink url="http://developer.gnome.org/gtkmm/3.22/classGtk_1_1Button.html"><classname>Gtk::Button</classname></ulink>. Standard buttons, usually
marked with a label or picture. Pushing one triggers an action. See the <link linkend="sec-pushbuttons">Button</link> section.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term>Bouton bascule</term>
<listitem>
<para lang="en">
<ulink url="http://developer.gnome.org/gtkmm/3.22/classGtk_1_1ToggleButton.html"><classname>Gtk::ToggleButton</classname></ulink>.
Unlike a normal Button, which springs back up, a ToggleButton stays down until you
press it again. It might be useful as an on/off switch. See the <link linkend="sec-toggle-buttons">ToggleButton</link> section.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term>Case à cocher</term>
<listitem>
<para lang="en">
<ulink url="http://developer.gnome.org/gtkmm/3.22/classGtk_1_1CheckButton.html"><classname>Gtk::CheckButton</classname></ulink>.
These act like ToggleButtons, but show their state in small squares,
with their label at the side. They should be used in most situations
which require an on/off setting.
See the <link linkend="sec-checkboxes">CheckButton</link> section.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term>Bouton radio</term>
<listitem>
<para lang="en">
<ulink url="http://developer.gnome.org/gtkmm/3.22/classGtk_1_1RadioButton.html"><classname>Gtk::RadioButton</classname></ulink>.
Named after the station selectors on old car
radios, these buttons are used in groups for options which are
mutually exclusive. Pressing one causes all the
others in its group to turn off. They are similar to
CheckBoxes (a small widget with a label at the side), but usually
look different.
See the <link linkend="sec-radio-buttons">RadioButton</link> section.
</para>
</listitem>
</varlistentry>
</variablelist>

<para>Notez qu'en raison du système des thèmes d'apparence de GTK+, l'aspect de ces éléments graphiques peut varier. Dans le cas des cases à cocher et des boutons radio, les variations peuvent être conséquentes.</para>

<sect1 id="sec-pushbuttons">
<title>Bouton</title>

<sect2 id="pushbutton-constructors"><title>Constructeurs</title>

<para>Il y a deux façons de créer un bouton. Vous pouvez indiquer la chaîne étiquette dans le constructeur de <classname>Gtk::Button</classname> ou bien la définir plus tard avec <methodname>set_label()</methodname>.</para>

<para>Pour définir une touche d'accès direct de navigation au clavier, placez un caractère souligné avant l'un des caractères de l'étiquette et définissez à <literal>true</literal> le paramètre optionnel <literal>mnemonic</literal> (mnémonique). Par exemple :</para>
<programlisting>Gtk::Button* pButton = new Gtk::Button("_Quelquechose", true);</programlisting>

<para lang="en">
Stock items have been recommended for use in buttons. From <application>gtkmm</application>-3.10 they are deprecated.
They should not be used in newly-written code. However, the documentation of
<ulink url="http://developer.gnome.org/gtkmm/3.22/namespaceGtk_1_1Stock.html">namespace Gtk::Stock</ulink>
shows recommended labels and named icons to show in buttons.
</para>

<para><classname>Gtk::Button</classname> est aussi un conteneur ; vous pouvez donc y mettre n'importe quel autre élément graphique à l'intérieur, comme une <classname>Gtk::Image</classname>.</para>

<para lang="en"><ulink url="http://developer.gnome.org/gtkmm/3.22/classGtk_1_1Button.html">Reference</ulink></para>
</sect2>

<sect2 id="pushbutton-example"><title>Exemple</title>

<para>Cet exemple crée un bouton avec image et étiquette.</para>

<figure id="figure-buttons">
  <title>Exemple de bouton</title>
  <screenshot>
    <graphic format="PNG" fileref="figures/buttons.png"/>
  </screenshot>
</figure>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/buttons/button?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>buttons.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLE_BUTTONS_H
#define GTKMM_EXAMPLE_BUTTONS_H

#include &lt;gtkmm/window.h&gt;
#include &lt;gtkmm/button.h&gt;

class Buttons : public Gtk::Window
{
public:
  Buttons();
  virtual ~Buttons();

protected:
  //Signal handlers:
  void on_button_clicked();

  //Child widgets:
  Gtk::Button m_button;
};

#endif //GTKMM_EXAMPLE_BUTTONS_H
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "buttons.h"
#include &lt;gtkmm/application.h&gt;

int main(int argc, char *argv[])
{
  auto app = Gtk::Application::create(argc, argv, "org.gtkmm.example");

  Buttons buttons;

  //Shows the window and returns when it is closed.
  return app-&gt;run(buttons);
}
</programlisting>
<para lang="en">File: <filename>buttons.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "buttons.h"
#include &lt;iostream&gt;

Buttons::Buttons()
{
  m_button.add_pixlabel("info.xpm", "cool button");

  set_title("Pixmap'd buttons!");
  set_border_width(10);

  m_button.signal_clicked().connect( sigc::mem_fun(*this,
              &amp;Buttons::on_button_clicked) );

  add(m_button);

  show_all_children();
}

Buttons::~Buttons()
{
}

void Buttons::on_button_clicked()
{
  std::cout &lt;&lt; "The Button was clicked." &lt;&lt; std::endl;
}
</programlisting>
<!-- end inserted example code -->

</sect2>

<sect2 id="pushbutton-signals"><title>Signaux</title>

<para lang="en">
The <classname>Gtk::Button</classname> widget has the following signals,
but all except the <literal>clicked</literal> signal are deprecated
and should not be used in newly-written code:
</para>

<para>
<variablelist>

<varlistentry>
<term lang="en"><literal>pressed</literal></term>
<listitem>
<para lang="en">
Emitted when the button is pressed.
Use <methodname>Gtk::Widget::signal_button_press_event()</methodname> instead.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term lang="en"><literal>released</literal></term>
<listitem>
<para lang="en">
Emitted when the button is released.
Use <methodname>Gtk::Widget::signal_button_release_event()</methodname> instead.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term lang="en"><literal>clicked</literal></term>
<listitem>
<para>Émis quand le bouton est enfoncé et relâché.</para>
</listitem>
</varlistentry>
<varlistentry>
<term lang="en"><literal>enter</literal></term>
<listitem>
<para lang="en">
Emitted when the mouse pointer enters the button's window.
Use <methodname>Gtk::Widget::signal_enter_notify_event()</methodname> instead.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term lang="en"><literal>leave</literal></term>
<listitem>
<para lang="en">
Emitted when the mouse pointer leaves the button's window.
Use <methodname>Gtk::Widget::signal_leave_notify_event()</methodname> instead.
</para>
</listitem>
</varlistentry>
</variablelist>
</para>

</sect2>
</sect1>

<sect1 id="sec-toggle-buttons">
<title>Bouton bascule</title>

<para>Un objet de la classe <classname>ToggleButton</classname> est semblable à un objet de la classe <classname>Button</classname>, mais les boutons bascules restent activés, ou enfoncés, jusqu'à ce qu'ils soient à nouveau cliqués. </para>

<para>Pour obtenir l'état du <classname>ToggleButton</classname>, utilisez la fonction membre <methodname>get_active()</methodname>. Elle renvoie <literal>true</literal> si le bouton est « enfoncé ». Vous pouvez aussi définir l'état du bouton bascule avec <methodname>set_active()</methodname>. Notez que, si vous faites cet appel et que l'état du bouton est effectivement modifié, le signal « clicked » sera émis : ce comportement est celui habituellement recherché.</para>

<para>Utilisez la fonction membre <methodname>toggled()</methodname> pour inverser l'état du bouton, au lieu de l'obliger à être enfoncé ou pas : l'état du bouton est modifié et le signal <literal>toggled</literal> (basculé) est émis.</para>

<para><classname>Gtk::ToggleButton</classname> est de grande utilité en tant que classe de base pour les classes <classname>Gtk::CheckButton</classname> et <classname>Gtk::RadioButton</classname>.</para>

<para lang="en"><ulink url="http://developer.gnome.org/gtkmm/3.22/classGtk_1_1ToggleButton.html">Reference</ulink></para>

</sect1>

<sect1 id="sec-checkboxes">
<title>Case à cocher</title>

<para>La classe <classname>Gtk::CheckButton</classname> hérite de la classe <classname>Gtk::ToggleButton</classname>. La seule réelle différence entre les deux classes se situe au niveau de l'aspect graphique du <classname>Gtk::CheckButton</classname>. Vous obtenez, définissez et inversez son état à l'aide des mêmes fonctions membres que <classname>Gtk::ToggleButton</classname>.</para>

<para lang="en"><ulink url="http://developer.gnome.org/gtkmm/3.22/classGtk_1_1CheckButton.html">Reference</ulink></para>

<sect2 id="checkbutton-example"><title>Exemple</title>

<figure id="figure-checkbutton">
  <title>Case à cocher</title>
  <screenshot>
    <graphic format="PNG" fileref="figures/checkbutton.png"/>
  </screenshot>
</figure>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/buttons/checkbutton?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>examplewindow.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLE_BUTTONS_H
#define GTKMM_EXAMPLE_BUTTONS_H

#include &lt;gtkmm/window.h&gt;
#include &lt;gtkmm/checkbutton.h&gt;

class ExampleWindow : public Gtk::Window
{
public:
  ExampleWindow();
  virtual ~ExampleWindow();

protected:
  //Signal handlers:
  void on_button_clicked();

  //Child widgets:
  Gtk::CheckButton m_button;
};

#endif //GTKMM_EXAMPLE_BUTTONS_H
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;gtkmm/application.h&gt;

int main(int argc, char *argv[])
{
  auto app = Gtk::Application::create(argc, argv, "org.gtkmm.example");

  ExampleWindow window;

  //Shows the window and returns when it is closed.
  return app-&gt;run(window);
}
</programlisting>
<para lang="en">File: <filename>examplewindow.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;iostream&gt;

ExampleWindow::ExampleWindow()
: m_button("something")
{
  set_title("checkbutton example");
  set_border_width(10);

  m_button.signal_clicked().connect(sigc::mem_fun(*this,
              &amp;ExampleWindow::on_button_clicked) );

  add(m_button);

  show_all_children();
}

ExampleWindow::~ExampleWindow()
{
}

void ExampleWindow::on_button_clicked()
{
  std::cout &lt;&lt; "The Button was clicked: state="
      &lt;&lt; (m_button.get_active() ? "true" : "false")
      &lt;&lt; std::endl;
}
</programlisting>
<!-- end inserted example code -->
</sect2>

</sect1>

<sect1 id="sec-radio-buttons">
<title>Bouton radio</title>

<para>De même que les cases à cocher, les boutons radio héritent aussi des propriétés des <classname>Gtk::ToggleButton</classname>, mais les boutons radio fonctionnent en groupe et, dans un groupe, un seul et unique bouton radio peut être sélectionné à un moment donné.</para>

<sect2 id="radiobutton-groups"><title>Groupes</title>
<para>Il y a deux façons de définir un groupe de boutons radio. La première est de créer les boutons et de définir leur groupement après-coup. Seuls les deux premiers constructeurs sont utilisés dans ce cas. Dans l'exemple suivant, nous créons une nouvelle classe de fenêtre nommée <classname>RadioButtons</classname> dans laquelle nous plaçons trois boutons radio :</para>

<programlisting lang="en">class RadioButtons : public Gtk::Window
{
public:
  RadioButtons();

protected:
  Gtk::RadioButton m_rb1, m_rb2, m_rb3;
};

RadioButtons::RadioButtons()
: m_rb1("button1"),
  m_rb2("button2"),
  m_rb3("button3")
{
  m_rb2.join_group(m_rb1);
  m_rb3.join_group(m_rb1);
}</programlisting>
<para lang="en">
We told <application>gtkmm</application> to put all three <classname>RadioButton</classname>s in the
same group by using <methodname>join_group()</methodname> to tell the other
<classname>RadioButton</classname>s to share group with the first
<classname>RadioButton</classname>.
</para>

<para lang="en">
Note that you can't do
<programlisting lang="en">m_rb2.set_group(m_rb1.get_group()); //doesn't work</programlisting>
because <methodname>get_group()</methodname> returns a <classname>RadioButton::Group</classname>
which is modified by <methodname>set_group()</methodname> and therefore is non-const.
</para>

<para>La deuxième façon pour grouper des boutons radio consiste à créer un groupement au préalable, puis y intégrer les boutons. Voici un exemple :</para>
<programlisting lang="en">class RadioButtons : public Gtk::Window
{
public:
  RadioButtons();
};

RadioButtons::RadioButtons()
{
  Gtk::RadioButton::Group group;
  Gtk::RadioButton* m_rb1 = Gtk::manage(new Gtk::RadioButton(group, "button1"));
  Gtk::RadioButton* m_rb2 = Gtk::manage(new Gtk::RadioButton(group, "button2"));
  Gtk::RadioButton* m_rb3 = Gtk::manage(new Gtk::RadioButton(group, "button3"));
}</programlisting>

<para>Nous générons un nouveau groupe par une simple déclaration de variable, <literal>group</literal>, du type <classname>Gtk::RadioButton::Group</classname>, puis nous créons trois boutons radio avec le constructeur indiquant qu'ils font partie du groupe <literal>group</literal>.</para>
</sect2>

<sect2 id="radiobutton-methods"><title>Fonctions membres</title>
<para>À leur création, les objets de la classe <classname>RadioButtons</classname> sont « inactifs », donc, lors de la création du groupe, tous les boutons sont désactivés. N'oubliez donc pas d'en activer un avec <methodname>set_active()</methodname> :</para>

<para lang="en"><ulink url="http://developer.gnome.org/gtkmm/3.22/classGtk_1_1RadioButton.html">Reference</ulink></para>

</sect2>

<sect2 id="radiobutton-example"><title>Exemple</title>
<para>L'exemple suivant montre l'utilisation de la classe <classname>RadioButton</classname> :</para>

<figure id="figure-radiobutton">
  <title>Bouton radio</title>
  <screenshot>
    <graphic format="PNG" fileref="figures/radiobuttons.png"/>
  </screenshot>
</figure>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/buttons/radiobutton?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>radiobuttons.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLE_RADIOBUTTONS_H
#define GTKMM_EXAMPLE_RADIOBUTTONS_H

#include &lt;gtkmm/box.h&gt;
#include &lt;gtkmm/window.h&gt;
#include &lt;gtkmm/radiobutton.h&gt;
#include &lt;gtkmm/separator.h&gt;

class RadioButtons : public Gtk::Window
{
public:
  RadioButtons();
  virtual ~RadioButtons();

protected:
  //Signal handlers:
  void on_button_clicked();

  //Child widgets:
  Gtk::Box m_Box_Top, m_Box1, m_Box2;
  Gtk::RadioButton m_RadioButton1, m_RadioButton2, m_RadioButton3;
  Gtk::Separator m_Separator;
  Gtk::Button m_Button_Close;
};

#endif //GTKMM_EXAMPLE_RADIOBUTTONS_H
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "radiobuttons.h"
#include &lt;gtkmm/application.h&gt;

int main(int argc, char *argv[])
{
  auto app = Gtk::Application::create(argc, argv, "org.gtkmm.example");

  RadioButtons buttons;

  //Shows the window and returns when it is closed.
  return app-&gt;run(buttons);
}
</programlisting>
<para lang="en">File: <filename>radiobuttons.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "radiobuttons.h"


RadioButtons::RadioButtons() :
  m_Box_Top(Gtk::ORIENTATION_VERTICAL),
  m_Box1(Gtk::ORIENTATION_VERTICAL, 10),
  m_Box2(Gtk::ORIENTATION_VERTICAL, 10),
  m_RadioButton1("button1"),
  m_RadioButton2("button2"),
  m_RadioButton3("button3"),
  m_Button_Close("close")
{
  // Set title and border of the window
  set_title("radio buttons");
  set_border_width(0);

  // Put radio buttons 2 and 3 in the same group as 1:
  m_RadioButton2.join_group(m_RadioButton1);
  m_RadioButton3.join_group(m_RadioButton1);

  // Add outer box to the window (because the window
  // can only contain a single widget)
  add(m_Box_Top);

  //Put the inner boxes and the separator in the outer box:
  m_Box_Top.pack_start(m_Box1);
  m_Box_Top.pack_start(m_Separator);
  m_Box_Top.pack_start(m_Box2);

  // Set the inner boxes' borders
  m_Box2.set_border_width(10);
  m_Box1.set_border_width(10);

  // Put the radio buttons in Box1:
  m_Box1.pack_start(m_RadioButton1);
  m_Box1.pack_start(m_RadioButton2);
  m_Box1.pack_start(m_RadioButton3);

  // Set the second button active
  m_RadioButton2.set_active();

  // Put Close button in Box2:
  m_Box2.pack_start(m_Button_Close);

  // Make the button the default widget
  m_Button_Close.set_can_default();
  m_Button_Close.grab_default();

  // Connect the clicked signal of the button to
  // RadioButtons::on_button_clicked()
  m_Button_Close.signal_clicked().connect(sigc::mem_fun(*this,
              &amp;RadioButtons::on_button_clicked) );

  // Show all children of the window
  show_all_children();
}

RadioButtons::~RadioButtons()
{
}

void RadioButtons::on_button_clicked()
{
  hide(); //to close the application.
}
</programlisting>
<!-- end inserted example code -->

</sect2>

</sect1>

</chapter>


<chapter id="chapter-range-widgets">
<title>Éléments graphiques à plage de réglage</title>

<para>Les classes <classname>Gtk::Scale</classname> et <classname>Gtk::Scrollbar</classname> dérivent toutes deux de <classname>Gtk::Range</classname>, elles partagent un grand nombre de fonctionnalités. Elles comportent une « glissière » (ou « coulisse ») et un « curseur » (quelquefois nommé « molette » dans d'autres environnements GUI). Vous déplacez le curseur dans la glissière en le faisant glisser à l'aide du pointeur de souris ; si vous cliquez dans la glissière, le curseur avance vers l'endroit cliqué, soit directement, soit d'un pas donné, selon le bouton de souris utilisé. C'est le comportement habituel des barres de défilement.</para>

<para>Ainsi que nous l'expliquons dans le chapitre <link linkend="chapter-adjustment">Ajustements</link>, tous les éléments graphiques à plage de réglage disposent d'un objet <classname>Adjustment</classname> associé. Pour modifier les valeurs minimale, maximale ou actuelles associées à la position du curseur dans l'élément graphique, vous devez utiliser les fonctions membres de la classe <classname>Adjustment</classname> dont on obtient le pointeur avec <methodname>get_adjustment()</methodname>. Les constructeurs d'un élément graphique à plage de réglage créent automatiquement, par défaut, un objet <classname>Adjustment</classname> ; vous pouvez aussi désigner un objet <classname>Adjustment</classname> préexistant, en vue peut-être de le partager avec un autre élément graphique. Consultez le chapitre <link linkend="chapter-adjustment">Ajustements</link> pour de plus amples détails.</para>

<para lang="en"><ulink url="http://developer.gnome.org/gtkmm/3.22/classGtk_1_1Range.html">Reference</ulink></para>

<sect1 id="sec-scrollbar-widgets">
<title>Éléments graphiques barres de défilement</title>

<para>Ce sont les barres de défilement classiques. Elles ne s'utilisent que pour déplacer un autre élément graphique, comme un <classname>Gtk::Entry</classname> ou un <classname>Gtk::Viewport</classname>, même s'il est habituellement plus facile d'utiliser un élément graphique de la classe <classname>Gtk::ScrolledWindow</classname> dans la plupart des cas.</para>

<para lang="en">
The orientation of a <classname>Gtk::Scrollbar</classname> can be either
horizontal or vertical.
</para>

<para lang="en"><ulink url="http://developer.gnome.org/gtkmm/3.22/classGtk_1_1Scrollbar.html">Reference</ulink></para>

</sect1>

<sect1 id="sec-scale-widgets">
<title>Éléments graphiques échelles de valeur</title>

<para>Les éléments graphiques de la classe <classname>Gtk::Scale</classname> (« coulisses », « glissières ») permettent à l'utilisateur de sélectionner et manipuler visuellement une valeur dans une plage donnée. Vous les utilisez, par exemple, pour ajuster le niveau de zoom de l'aperçu d'une image, pour contrôler la luminosité d'une couleur ou bien pour définir le nombre de minutes d'inactivité avant le déclenchement de l'économiseur d'écran.</para>

<para lang="en">
As with <classname>Scrollbar</classname>s, the orientation can be either
horizontal or vertical. The default constructor creates an
<classname>Adjustment</classname> with all of its values set to
<literal>0.0</literal>. This isn't useful so you will need to set some
<classname>Adjustment</classname> details to get meaningful behaviour.
</para>

<sect2 id="scale-useful-methods">
<title>Fonctions membres utiles</title>

<para>Les éléments graphiques de la classe <classname>Scale</classname> peuvent afficher la valeur correspondant à la position actuelle du curseur sous forme d'un nombre près de la glissière. C'est le comportement par défaut, mais vous pouvez modifier ce dernier avec la fonction membre <methodname>set_draw_value()</methodname>.</para>

<para>La valeur affichée par un élément graphique coulisse est, par défaut, arrondie à un chiffre après la virgule ; cette valeur affichée correspond à celle du champ <literal>value</literal> de l'objet <classname>Gtk::Adjustment</classname> associé. Vous pouvez modifier la précision avec la fonction membre <methodname>set_digits()</methodname>.</para>

<para>En outre, la valeur peut être placée à diverses positions par rapport à la glissière ; la position se définit avec la fonction membre <methodname>set_value_pos()</methodname>.</para>

<para lang="en"><ulink url="http://developer.gnome.org/gtkmm/3.22/classGtk_1_1Scale.html">Reference</ulink></para>

</sect2>
</sect1>

<sect1 id="sec-range-example">
<title>Exemple</title>

<para>Cet exemple affiche une fenêtre avec trois éléments graphiques coulisses tous connectés au même ajustement. À côté, sont disposés quelques contrôles pour ajuster certains paramètres mentionnés plus haut (et rappelés au chapitre Ajustements) : vous pouvez ainsi voir comment ils modifient la façon dont ces éléments graphiques réagissent vis à vis de l'utilisateur.</para>

<figure id="figure-range-widgets">
  <title>Éléments graphiques à plage de réglage</title>
  <screenshot>
    <graphic format="PNG" fileref="figures/range_widgets.png"/>
  </screenshot>
</figure>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/range_widgets?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>examplewindow.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLE_RANGEWIDGETS_H
#define GTKMM_EXAMPLE_RANGEWIDGETS_H

#include &lt;gtkmm.h&gt;

class ExampleWindow : public Gtk::Window
{
public:
  ExampleWindow();
  virtual ~ExampleWindow();

protected:
  //Signal handlers:
  void on_checkbutton_toggled();
  void on_combo_position();
  void on_adjustment1_value_changed();
  void on_adjustment2_value_changed();
  void on_button_quit();

  //Child widgets:
  Gtk::Box m_VBox_Top, m_VBox2, m_VBox_HScale;
  Gtk::Box m_HBox_Scales, m_HBox_Combo, m_HBox_Digits, m_HBox_PageSize;

  Glib::RefPtr&lt;Gtk::Adjustment&gt; m_adjustment, m_adjustment_digits, m_adjustment_pagesize;

  Gtk::Scale m_VScale;
  Gtk::Scale m_HScale, m_Scale_Digits, m_Scale_PageSize;

  Gtk::Separator m_Separator;

  Gtk::CheckButton m_CheckButton;

  Gtk::Scrollbar m_Scrollbar;

  //Tree model columns:
  class ModelColumns : public Gtk::TreeModel::ColumnRecord
  {
  public:

    ModelColumns()
    { add(m_col_position_type); add(m_col_title); }

    Gtk::TreeModelColumn&lt;Gtk::PositionType&gt; m_col_position_type;
    Gtk::TreeModelColumn&lt;Glib::ustring&gt; m_col_title;
  };

  ModelColumns m_Columns;

  //Child widgets:
  Gtk::ComboBox m_ComboBox_Position;
  Glib::RefPtr&lt;Gtk::ListStore&gt; m_refTreeModel;

  Gtk::Button m_Button_Quit;
};

#endif //GTKMM_EXAMPLE_RANGEWIDGETS_H
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;gtkmm/application.h&gt;

int main(int argc, char *argv[])
{
  auto app = Gtk::Application::create(argc, argv, "org.gtkmm.example");

  ExampleWindow window;

  //Shows the window and returns when it is closed.
  return app-&gt;run(window);
}
</programlisting>
<para lang="en">File: <filename>examplewindow.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;iostream&gt;

ExampleWindow::ExampleWindow()
:
  m_VBox_Top(Gtk::ORIENTATION_VERTICAL, 0),
  m_VBox2(Gtk::ORIENTATION_VERTICAL, 20),
  m_VBox_HScale(Gtk::ORIENTATION_VERTICAL, 10),
  m_HBox_Scales(Gtk::ORIENTATION_HORIZONTAL, 10),
  m_HBox_Combo(Gtk::ORIENTATION_HORIZONTAL, 10),
  m_HBox_Digits(Gtk::ORIENTATION_HORIZONTAL, 10),
  m_HBox_PageSize(Gtk::ORIENTATION_HORIZONTAL, 10),

  // Value, lower, upper, step_increment, page_increment, page_size:
  // Note that the page_size value only makes a difference for
  // scrollbar widgets, and the highest value you'll get is actually
  // (upper - page_size).
  m_adjustment( Gtk::Adjustment::create(0.0, 0.0, 101.0, 0.1, 1.0, 1.0) ),
  m_adjustment_digits( Gtk::Adjustment::create(1.0, 0.0, 5.0, 1.0, 2.0) ),
  m_adjustment_pagesize( Gtk::Adjustment::create(1.0, 1.0, 101.0) ),

  m_VScale(m_adjustment, Gtk::ORIENTATION_VERTICAL),
  m_HScale(m_adjustment, Gtk::ORIENTATION_HORIZONTAL),
  m_Scale_Digits(m_adjustment_digits),
  m_Scale_PageSize(m_adjustment_pagesize),

  // A checkbutton to control whether the value is displayed or not:
  m_CheckButton("Display value on scale widgets", 0),

  // Reuse the same adjustment again.
  // Notice how this causes the scales to always be updated
  // continuously when the scrollbar is moved.
  m_Scrollbar(m_adjustment),

  m_Button_Quit("Quit")
{
  set_title("range controls");
  set_default_size(300, 350);

  //VScale:
  m_VScale.set_digits(1);
  m_VScale.set_value_pos(Gtk::POS_TOP);
  m_VScale.set_draw_value();
  m_VScale.set_inverted(); // highest value at top

  //HScale:
  m_HScale.set_digits(1);
  m_HScale.set_value_pos(Gtk::POS_TOP);
  m_HScale.set_draw_value();

  add(m_VBox_Top);
  m_VBox_Top.pack_start(m_VBox2);
  m_VBox2.set_border_width(10);
  m_VBox2.pack_start(m_HBox_Scales);

  //Put VScale and HScale (above scrollbar) side-by-side.
  m_HBox_Scales.pack_start(m_VScale);
  m_HBox_Scales.pack_start(m_VBox_HScale);

  m_VBox_HScale.pack_start(m_HScale);

  //Scrollbar:
  m_VBox_HScale.pack_start(m_Scrollbar);

  //CheckButton:
  m_CheckButton.set_active();
  m_CheckButton.signal_toggled().connect( sigc::mem_fun(*this,
    &amp;ExampleWindow::on_checkbutton_toggled) );
  m_VBox2.pack_start(m_CheckButton, Gtk::PACK_SHRINK);

  //Position ComboBox:
  //Create the Tree model:
  m_refTreeModel = Gtk::ListStore::create(m_Columns);
  m_ComboBox_Position.set_model(m_refTreeModel);
  m_ComboBox_Position.pack_start(m_Columns.m_col_title);

  //Fill the ComboBox's Tree Model:
  Gtk::TreeModel::Row row = *(m_refTreeModel-&gt;append());
  row[m_Columns.m_col_position_type] = Gtk::POS_TOP;
  row[m_Columns.m_col_title] = "Top";
  row = *(m_refTreeModel-&gt;append());
  row[m_Columns.m_col_position_type] = Gtk::POS_BOTTOM;
  row[m_Columns.m_col_title] = "Bottom";
  row = *(m_refTreeModel-&gt;append());
  row[m_Columns.m_col_position_type] = Gtk::POS_LEFT;
  row[m_Columns.m_col_title] = "Left";
  row = *(m_refTreeModel-&gt;append());
  row[m_Columns.m_col_position_type] = Gtk::POS_RIGHT;
  row[m_Columns.m_col_title] = "Right";

  m_VBox2.pack_start(m_HBox_Combo, Gtk::PACK_SHRINK);
  m_HBox_Combo.pack_start(
    *Gtk::manage(new Gtk::Label("Scale Value Position:", 0)), Gtk::PACK_SHRINK);
  m_HBox_Combo.pack_start(m_ComboBox_Position);
  m_ComboBox_Position.signal_changed().connect( sigc::mem_fun(*this, &amp;ExampleWindow::on_combo_position) );
  m_ComboBox_Position.set_active(0); // Top

  //Digits:
  m_HBox_Digits.pack_start(
    *Gtk::manage(new Gtk::Label("Scale Digits:", 0)), Gtk::PACK_SHRINK);
  m_Scale_Digits.set_digits(0);
  m_adjustment_digits-&gt;signal_value_changed().connect(sigc::mem_fun(*this,
    &amp;ExampleWindow::on_adjustment1_value_changed));
  m_HBox_Digits.pack_start(m_Scale_Digits);

  //Page Size:
  m_HBox_PageSize.pack_start(
    *Gtk::manage(new Gtk::Label("Scrollbar Page Size:", 0)),
    Gtk::PACK_SHRINK);
  m_Scale_PageSize.set_digits(0);
  m_adjustment_pagesize-&gt;signal_value_changed().connect(sigc::mem_fun(*this,
    &amp;ExampleWindow::on_adjustment2_value_changed));
  m_HBox_PageSize.pack_start(m_Scale_PageSize);

  m_VBox2.pack_start(m_HBox_Digits, Gtk::PACK_SHRINK);
  m_VBox2.pack_start(m_HBox_PageSize, Gtk::PACK_SHRINK);
  m_VBox_Top.pack_start(m_Separator, Gtk::PACK_SHRINK);
  m_VBox_Top.pack_start(m_Button_Quit, Gtk::PACK_SHRINK);

  m_Button_Quit.set_can_default();
  m_Button_Quit.grab_default();
  m_Button_Quit.signal_clicked().connect(sigc::mem_fun(*this,
    &amp;ExampleWindow::on_button_quit));
  m_Button_Quit.set_border_width(10);

  show_all_children();
}

ExampleWindow::~ExampleWindow()
{
}

void ExampleWindow::on_checkbutton_toggled()
{
  m_VScale.set_draw_value(m_CheckButton.get_active());
  m_HScale.set_draw_value(m_CheckButton.get_active());
}

void ExampleWindow::on_combo_position()
{
  Gtk::TreeModel::iterator iter = m_ComboBox_Position.get_active();
  if(!iter)
    return;

  Gtk::TreeModel::Row row = *iter;
  if(!row)
    return;

  const Gtk::PositionType postype = row[m_Columns.m_col_position_type];

  m_VScale.set_value_pos(postype);
  m_HScale.set_value_pos(postype);
}

void ExampleWindow::on_adjustment1_value_changed()
{
  const double val = m_adjustment_digits-&gt;get_value();
  m_VScale.set_digits((int)val);
  m_HScale.set_digits((int)val);
}

void ExampleWindow::on_adjustment2_value_changed()
{
  const double val = m_adjustment_pagesize-&gt;get_value();
  m_adjustment-&gt;set_page_size(val);
  m_adjustment-&gt;set_page_increment(val);

  // Note that we don't have to emit the "changed" signal
  // because gtkmm does this for us.
}

void ExampleWindow::on_button_quit()
{
  hide();
}
</programlisting>
<!-- end inserted example code -->

</sect1>

</chapter>

<chapter id="chapter-misc-widgets">
<title>Éléments graphiques divers</title>

<sect1 id="sec-labels">
<title>Étiquette</title>

<para lang="en">
Labels are the  main method of placing non-editable text in windows, for
instance to place a title next to a <classname>Entry</classname> widget. You
can specify the text in the constructor, or later with the
<methodname>set_text()</methodname> or <methodname>set_markup()</methodname> methods.
</para>

<para>La largeur de l'étiquette sera ajustée automatiquement. Vous pouvez écrire des étiquettes sur plusieurs lignes en mettant des sauts de ligne (« \n ») dans la chaîne de l'étiquette.</para>

<para>Le texte de l'étiquette peut être justifié avec la fonction membre <methodname>set_justify()</methodname>. L'élément graphique est également susceptible de prendre en charge le retour à ligne automatique, fonctionnalité activée avec la fonction membre <methodname>set_line_wrap()</methodname>.</para>

<para lang="en">
Gtk::Label support some simple formatting, for instance allowing you to make some
text bold, colored, or larger. You can do this by providing a string to
<methodname>set_markup()</methodname>, using the <ulink url="http://developer.gnome.org/pango/unstable/PangoMarkupFormat.html">Pango Markup syntax</ulink>. For instance,
<code>
&lt;b&gt;bold text&lt;/b&gt; and &lt;s&gt;strikethrough text&lt;/s&gt;
</code>
.</para>

<para lang="en"><ulink url="http://developer.gnome.org/gtkmm/3.22/classGtk_1_1Label.html">Reference</ulink></para>

<sect2 id="label-example"><title>Exemple</title>
<para lang="en">
Below is a short example to illustrate these functions. This example
makes use of the Frame widget to better demonstrate the label styles.
 (The Frame widget is explained in the <link linkend="sec-frame">Frame</link> section.)
It is possible that the first character in <literal>m_Label_Normal</literal> is shown
underlined only when you press the <keycap>Alt</keycap> key.
</para>

<figure id="figure-label">
  <title>Étiquette</title>
  <screenshot>
    <graphic format="PNG" fileref="figures/label.png"/>
  </screenshot>
</figure>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/label?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>examplewindow.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLEWINDOW_H
#define GTKMM_EXAMPLEWINDOW_H

#include &lt;gtkmm.h&gt;

class ExampleWindow : public Gtk::Window
{
public:
  ExampleWindow();
  virtual ~ExampleWindow();

protected:

  //Child widgets:
  Gtk::Box m_HBox;
  Gtk::Box m_VBox, m_VBox2;
  Gtk::Frame m_Frame_Normal, m_Frame_Multi, m_Frame_Left, m_Frame_Right,
    m_Frame_LineWrapped, m_Frame_FilledWrapped, m_Frame_Underlined;
  Gtk::Label m_Label_Normal, m_Label_Multi, m_Label_Left, m_Label_Right,
    m_Label_LineWrapped, m_Label_FilledWrapped, m_Label_Underlined;
};

#endif //GTKMM_EXAMPLEWINDOW_H
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;gtkmm/application.h&gt;

int main(int argc, char *argv[])
{
  auto app = Gtk::Application::create(argc, argv, "org.gtkmm.example");

  ExampleWindow window;

  //Shows the window and returns when it is closed.
  return app-&gt;run(window);
}
</programlisting>
<para lang="en">File: <filename>examplewindow.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;iostream&gt;

ExampleWindow::ExampleWindow()
:
  m_HBox(Gtk::ORIENTATION_HORIZONTAL, 5),
  m_VBox(Gtk::ORIENTATION_VERTICAL, 5),
  m_VBox2(Gtk::ORIENTATION_VERTICAL, 5),
  m_Frame_Normal("Normal Label"),
  m_Frame_Multi("Multi-line Label"),
  m_Frame_Left("Left Justified Label"),
  m_Frame_Right("Right Justified Label"),
  m_Frame_LineWrapped("Line wrapped label"),
  m_Frame_FilledWrapped("Filled, wrapped label"),
  m_Frame_Underlined("Underlined label"),
  m_Label_Normal("_This is a Normal label", true),
  m_Label_Multi("This is a Multi-line label.\nSecond line\nThird line"),
  m_Label_Left("This is a Left-Justified\nMulti-line label.\nThird line"),
  m_Label_Right("This is a Right-Justified\nMulti-line label.\nThird line"),
  m_Label_Underlined("This label is underlined!\n"
          "This one is underlined in quite a funky fashion")
{
  set_title("Label");
  set_border_width(5);

  add(m_HBox);

  m_HBox.pack_start(m_VBox, Gtk::PACK_SHRINK);

  m_Frame_Normal.add(m_Label_Normal);
  m_VBox.pack_start(m_Frame_Normal, Gtk::PACK_SHRINK);

  m_Frame_Multi.add(m_Label_Multi);
  m_VBox.pack_start(m_Frame_Multi, Gtk::PACK_SHRINK);

  m_Label_Left.set_justify(Gtk::JUSTIFY_LEFT);
  m_Frame_Left.add(m_Label_Left);
  m_VBox.pack_start(m_Frame_Left, Gtk::PACK_SHRINK);

  m_Label_Right.set_justify(Gtk::JUSTIFY_RIGHT);
  m_Frame_Right.add(m_Label_Right);
  m_VBox.pack_start(m_Frame_Right, Gtk::PACK_SHRINK);

  m_HBox.pack_start(m_VBox2, Gtk::PACK_SHRINK);

  m_Label_LineWrapped.set_text(
          "This is an example of a line-wrapped label.  It "
          /* add a big space to the next line to test spacing */
          "should not be taking up the entire             "
          "width allocated to it, but automatically "
          "wraps the words to fit.  "
          "The time has come, for all good men, to come to "
          "the aid of their party.  "
          "The sixth sheik's six sheep's sick.\n"
          "     It supports multiple paragraphs correctly, "
          "and  correctly   adds "
          "many          extra  spaces. ");
  m_Label_LineWrapped.set_line_wrap();
  m_Frame_LineWrapped.add(m_Label_LineWrapped);
  m_VBox2.pack_start(m_Frame_LineWrapped, Gtk::PACK_SHRINK);

  m_Label_FilledWrapped.set_text(
          "This is an example of a line-wrapped, filled label.  "
          "It should be taking "
          "up the entire              width allocated to it.  "
          "Here is a sentence to prove "
          "my point.  Here is another sentence. "
          "Here comes the sun, do de do de do.\n"
          "    This is a new paragraph.\n"
          "    This is another newer, longer, better "
          "paragraph.  It is coming to an end, "
          "unfortunately.");
  m_Label_FilledWrapped.set_justify(Gtk::JUSTIFY_FILL);
  m_Label_FilledWrapped.set_line_wrap();
  m_Frame_FilledWrapped.add(m_Label_FilledWrapped);
  m_VBox2.pack_start(m_Frame_FilledWrapped, Gtk::PACK_SHRINK);

  m_Label_Underlined.set_justify(Gtk::JUSTIFY_LEFT);
  m_Label_Underlined.set_pattern (
          "_________________________ _ _________ _ ______"
          "     __ _______ ___");
  m_Frame_Underlined.add(m_Label_Underlined);
  m_VBox2.pack_start(m_Frame_Underlined, Gtk::PACK_SHRINK);

  show_all_children();
}

ExampleWindow::~ExampleWindow()
{
}
</programlisting>
<!-- end inserted example code -->

</sect2>

</sect1>

<sect1 id="sec-text-entry">
<title>Champ de saisie</title>

<sect2 id="sec-text-entry-simple">
<title>Utilisation simple</title>

<para>Les éléments graphiques <classname>Entry</classname> permettent à l'utilisateur de saisir du texte. Vous pouvez en modifier le contenu avec la fonction membre <methodname>set_text()</methodname> et en lire le contenu actuel avec la fonction membre <methodname>get_text()</methodname>.</para>

<para>Parfois, vous voudrez que le contenu d'un élément graphique <classname>Entry</classname> soit en lecture seule. Vous obtenez ce résultat en passant le paramètre <literal>false</literal> à la fonction membre <methodname>set_editable()</methodname>.</para>

<para>Pour la saisie de mots de passe, phrases de passe et autres informations que vous ne souhaitez pas voir reprises à l'affichage, l'appel de la fonction membre <methodname>set_visibility()</methodname> avec <literal>false</literal> comme paramètre provoque le masquage du texte.</para>

<para lang="en">
You might want to be notified whenever the user types in a text entry widget.
<classname>Gtk::Entry</classname> provides two signals,
<literal>activate</literal> and <literal>changed</literal>, for this purpose.
<literal>activate</literal> is emitted when the user presses the Enter key in
a text-entry widget; <literal>changed</literal> is emitted when the text in
the widget changes. You can use these, for instance, to validate or filter
the text the user types. Moving the keyboard focus to another widget may also
signal that the user has finished entering text. The <literal>focus_out_event</literal>
signal that <classname>Gtk::Entry</classname> inherits from
<classname>Gtk::Widget</classname> can notify you when that happens.
The <link linkend="sec-comboboxentry">ComboBox with an Entry</link> section
contains example programs that use these signals.
</para>

<para lang="en">
If you pass <literal>true</literal> to the <methodname>set_activates_default()</methodname>
method, pressing Enter in the <classname>Gtk::Entry</classname> will activate
the default widget for the window containing the <classname>Gtk::Entry</classname>.
This is especially useful in dialog boxes. The default widget is usually one of
the dialog buttons, which e.g. will close the dialog box. To set a widget as the
default widget, use <methodname>Gtk::Widget::set_can_default()</methodname> and
<methodname>Gtk::Widget::grab_default()</methodname>.
</para>

<para lang="en"><ulink url="http://developer.gnome.org/gtkmm/3.22/classGtk_1_1Entry.html">Reference</ulink></para>

<sect3 id="entry-example"><title>Exemple simple de saisie</title>
<para>Cet exemple utilise la classe <classname>Gtk::Entry</classname>. Deux cases à cocher de la classe <classname>CheckButton</classname> vous permettent d'inverser les marqueurs « editable » et « visible ».</para>

<figure id="figure-entry-simple">
  <title>Champ de saisie</title>
  <screenshot>
    <graphic format="PNG" fileref="figures/entry.png"/>
  </screenshot>
</figure>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/entry/simple?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>examplewindow.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLEWINDOW_H
#define GTKMM_EXAMPLEWINDOW_H

#include &lt;gtkmm.h&gt;

class ExampleWindow : public Gtk::Window
{
public:
  ExampleWindow();
  virtual ~ExampleWindow();

protected:
  //Signal handlers:
  void on_checkbox_editable_toggled();
  void on_checkbox_visibility_toggled();
  void on_button_close();

  //Child widgets:
  Gtk::Box m_HBox;
  Gtk::Box m_VBox;
  Gtk::Entry m_Entry;
  Gtk::Button m_Button_Close;
  Gtk::CheckButton m_CheckButton_Editable, m_CheckButton_Visible;
};

#endif //GTKMM_EXAMPLEWINDOW_H
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;gtkmm/application.h&gt;

int main(int argc, char *argv[])
{
  auto app = Gtk::Application::create(argc, argv, "org.gtkmm.example");

  ExampleWindow window;

  //Shows the window and returns when it is closed.
  return app-&gt;run(window);
}
</programlisting>
<para lang="en">File: <filename>examplewindow.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;iostream&gt;

ExampleWindow::ExampleWindow()
: m_VBox(Gtk::ORIENTATION_VERTICAL),
  m_Button_Close("Close"),
  m_CheckButton_Editable("Editable"),
  m_CheckButton_Visible("Visible")
{
  set_size_request(200, 100);
  set_title("Gtk::Entry");

  add(m_VBox);

  m_Entry.set_max_length(50);
  m_Entry.set_text("hello");
  m_Entry.set_text(m_Entry.get_text() + " world");
  m_Entry.select_region(0, m_Entry.get_text_length());
  m_VBox.pack_start(m_Entry);

  // Note that add() can also be used instead of pack_xxx()
  m_VBox.add(m_HBox);

  m_HBox.pack_start(m_CheckButton_Editable);
  m_CheckButton_Editable.signal_toggled().connect( sigc::mem_fun(*this,
              &amp;ExampleWindow::on_checkbox_editable_toggled) );
  m_CheckButton_Editable.set_active(true);

  m_HBox.pack_start(m_CheckButton_Visible);
  m_CheckButton_Visible.signal_toggled().connect( sigc::mem_fun(*this,
              &amp;ExampleWindow::on_checkbox_visibility_toggled) );
  m_CheckButton_Visible.set_active(true);

  m_Button_Close.signal_clicked().connect( sigc::mem_fun(*this,
              &amp;ExampleWindow::on_button_close) );
  m_VBox.pack_start(m_Button_Close);
  m_Button_Close.set_can_default();
  m_Button_Close.grab_default();

  show_all_children();
}

ExampleWindow::~ExampleWindow()
{
}

void ExampleWindow::on_checkbox_editable_toggled()
{
  m_Entry.set_editable(m_CheckButton_Editable.get_active());
}

void ExampleWindow::on_checkbox_visibility_toggled()
{
  m_Entry.set_visibility(m_CheckButton_Visible.get_active());
}

void ExampleWindow::on_button_close()
{
  hide();
}

</programlisting>
<!-- end inserted example code -->

</sect3>

</sect2>

<sect2 id="sec-text-entry-completion">
<title>Complétion de saisie</title>
<para>Un élément graphique <classname>Entry</classname> peut offrir une liste déroulante de choix préétablis à partir des premiers caractères saisis par l'utilisateur. Par exemple, une boîte de dialogue de recherche peut suggérer un texte en fonction des recherches antérieures.</para>

<para>Pour activer cette fonctionnalité, vous devez créer un objet <classname>EntryCompletion</classname> et le mettre à disposition de l'élément graphique <classname>Entry</classname> par l'intermédiaire de la fonction membre <methodname>set_completion()</methodname>.</para>

<para>L'objet <classname>EntryCompletion</classname> peut utiliser une classe <classname>TreeModel</classname> contenant les entrées possibles définies à l'aide de <methodname>set_model()</methodname>. Faites ensuite appel à <methodname>set_text_column()</methodname> pour définir quelles colonnes de votre modèle doivent être utilisées pour chercher une possible concordance avec le texte saisi.</para>

<para lang="en">Alternatively, if a complete list of possible entries
would be too large or too inconvenient to generate, a callback slot may instead
be specified with <methodname>set_match_func()</methodname>.
This is also useful if you wish to match on a part of the string other
than the start.</para>

<para lang="en"><ulink url="http://developer.gnome.org/gtkmm/3.22/classGtk_1_1EntryCompletion.html">Reference</ulink></para>

<sect3 id="entry-completion-example"><title>Exemple de complétion de saisie</title>
<para>Dans cet exemple, nous créons un objet <classname>Gtk::EntryCompletion</classname> et nous l'associons à un élément graphique <classname>Gtk::Entry</classname>. La complétion fait appel à un objet <classname>Gtk::TreeModel</classname> pour les diverses saisies possibles et quelques actions supplémentaires.</para>

<figure id="figure-entry-completion">
  <title>Complétion de saisie</title>
  <screenshot>
    <graphic format="PNG" fileref="figures/entry_completion.png"/>
  </screenshot>
</figure>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/entry/completion?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>examplewindow.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLEWINDOW_H
#define GTKMM_EXAMPLEWINDOW_H

#include &lt;gtkmm.h&gt;

class ExampleWindow : public Gtk::Window
{
public:
  ExampleWindow();
  virtual ~ExampleWindow();

protected:
  //Signal handlers:
  void on_button_close();

  void on_completion_action_activated(int index);

  //See the comment in the implementation:
  //bool on_completion_match(const Glib::ustring&amp; key, const Gtk::TreeModel::const_iterator&amp; iter);


  //Tree model columns, for the EntryCompletion's filter model:
  class ModelColumns : public Gtk::TreeModel::ColumnRecord
  {
  public:

    ModelColumns()
    { add(m_col_id); add(m_col_name); }

    Gtk::TreeModelColumn&lt;unsigned int&gt; m_col_id;
    Gtk::TreeModelColumn&lt;Glib::ustring&gt; m_col_name;
  };

  ModelColumns m_Columns;

  typedef std::map&lt;int, Glib::ustring&gt; type_actions_map;
  type_actions_map m_CompletionActions;

  //Child widgets:
  Gtk::Box m_HBox;
  Gtk::Box m_VBox;
  Gtk::Entry m_Entry;
  Gtk::Label m_Label;
  Gtk::Button m_Button_Close;
};

#endif //GTKMM_EXAMPLEWINDOW_H
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;gtkmm/application.h&gt;

int main(int argc, char *argv[])
{
  auto app = Gtk::Application::create(argc, argv, "org.gtkmm.example");

  ExampleWindow window;

  //Shows the window and returns when it is closed.
  return app-&gt;run(window);
}
</programlisting>
<para lang="en">File: <filename>examplewindow.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;iostream&gt;

ExampleWindow::ExampleWindow()
: m_VBox(Gtk::ORIENTATION_VERTICAL),
  m_Label("Press a or b to see a list of possible completions and actions."),
  m_Button_Close("Close")
{
  //set_size_request(200, 100);
  set_title("Gtk::EntryCompletion");

  add(m_VBox);
  m_VBox.pack_start(m_Entry, Gtk::PACK_SHRINK);

  m_VBox.pack_start(m_Label, Gtk::PACK_EXPAND_WIDGET);

  m_Button_Close.signal_clicked().connect( sigc::mem_fun(*this,
              &amp;ExampleWindow::on_button_close) );
  m_VBox.pack_start(m_Button_Close, Gtk::PACK_SHRINK);
  m_Button_Close.set_can_default();
  m_Button_Close.grab_default();

  //Add an EntryCompletion:
  auto completion =
      Gtk::EntryCompletion::create();
  m_Entry.set_completion(completion);

  //Create and fill the completion's filter model
  auto refCompletionModel =
      Gtk::ListStore::create(m_Columns);
  completion-&gt;set_model(refCompletionModel);

  // For more complex comparisons, use a filter match callback, like this.
  // See the comment below for more details:
  //completion-&gt;set_match_func( sigc::mem_fun(*this,
              //&amp;ExampleWindow::on_completion_match) );

  //Fill the TreeView's model
  Gtk::TreeModel::Row row = *(refCompletionModel-&gt;append());
  row[m_Columns.m_col_id] = 1;
  row[m_Columns.m_col_name] = "Alan Zebedee";

  row = *(refCompletionModel-&gt;append());
  row[m_Columns.m_col_id] = 2;
  row[m_Columns.m_col_name] = "Adrian Boo";

  row = *(refCompletionModel-&gt;append());
  row[m_Columns.m_col_id] = 3;
  row[m_Columns.m_col_name] = "Bob McRoberts";

  row = *(refCompletionModel-&gt;append());
  row[m_Columns.m_col_id] = 4;
  row[m_Columns.m_col_name] = "Bob McBob";

  //Tell the completion what model column to use to
  //- look for a match (when we use the default matching, instead of
  //  set_match_func().
  //- display text in the entry when a match is found.
  completion-&gt;set_text_column(m_Columns.m_col_name);

  //Add actions to the completion:
  //These are just extra items shown at the bottom of the list of possible
  //completions.

  //Remember them for later.
  m_CompletionActions[0] = "Use Wizard";
  m_CompletionActions[1] = "Browse for Filename";

  for(const auto&amp; the_pair : m_CompletionActions)
  {
    auto position = the_pair.first;
    auto title = the_pair.second;
    completion-&gt;insert_action_text(title, position);
  }

  completion-&gt;signal_action_activated().connect( sigc::mem_fun(*this,
              &amp;ExampleWindow::on_completion_action_activated) );

  show_all_children();
}

ExampleWindow::~ExampleWindow()
{
}

void ExampleWindow::on_button_close()
{
  hide();
}

/* You can do more complex matching with a handler like this.
 * For instance, you could check for substrings inside the string instead of the start,
 * or you could look for the key in extra model columns as well as the model column that will be displayed.
 * The code here is not actually more complex - it's a reimplementation of the default behaviour.
 *
bool ExampleWindow::on_completion_match(const Glib::ustring&amp; key, const
        Gtk::TreeModel::const_iterator&amp; iter)
{
  if(iter)
  {
    Gtk::TreeModel::Row row = *iter;

    Glib::ustring::size_type key_length = key.size();
    Glib::ustring filter_string = row[m_Columns.m_col_name];

    Glib::ustring filter_string_start = filter_string.substr(0, key_length);
    //The key is lower-case, even if the user input is not.
    filter_string_start = filter_string_start.lowercase();

    if(key == filter_string_start)
      return true; //A match was found.
  }

  return false; //No match.
}
*/

void ExampleWindow::on_completion_action_activated(int index)
{
  type_actions_map::iterator iter = m_CompletionActions.find(index);
  if(iter != m_CompletionActions.end()) //If it's in the map
  {
    Glib::ustring title = iter-&gt;second;
    std::cout &lt;&lt; "Action selected: " &lt;&lt; title &lt;&lt; std::endl;
  }
}

</programlisting>
<!-- end inserted example code -->

</sect3>
</sect2>

<sect2 id="sec-text-entry-icons">
<title>Icône dans un champ de saisie</title>
<para lang="en">An <classname>Entry</classname> widget can show an icon at the start or
end of the text area. The icon can be specifed by methods such as
<methodname>set_icon_from_pixbuf()</methodname> or
<methodname>set_icon_from_icon_name()</methodname>. An application can respond to the
user pressing the icon by handling the
<methodname>signal_icon_press</methodname> signal.</para>

<sect3 id="entry-icon-example"><title>Exemple d'icône dans un champ de saisie</title>
<para lang="en">
This example shows a <classname>Gtk::Entry</classname> widget with a named
search icon, and prints text to the terminal when the icon is pressed.
</para>

<figure id="figure-entry-icon">
  <title>Saisie avec icône</title>
  <screenshot>
    <graphic format="PNG" fileref="figures/entry_icon.png"/>
  </screenshot>
</figure>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/entry/icon?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>examplewindow.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLEWINDOW_H
#define GTKMM_EXAMPLEWINDOW_H

#include &lt;gtkmm.h&gt;

class ExampleWindow : public Gtk::Window
{
public:
  ExampleWindow();
  virtual ~ExampleWindow();

protected:
  //Signal handlers:
  void on_icon_pressed(Gtk::EntryIconPosition icon_pos, const GdkEventButton* event);
  void on_button_close();

  //Child widgets:
  Gtk::Box m_VBox;
  Gtk::Entry m_Entry;
  Gtk::Button m_Button_Close;
};

#endif //GTKMM_EXAMPLEWINDOW_H
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;gtkmm/application.h&gt;

int main(int argc, char *argv[])
{
  auto app = Gtk::Application::create(argc, argv, "org.gtkmm.example");

  ExampleWindow window;

  //Shows the window and returns when it is closed.
  return app-&gt;run(window);
}
</programlisting>
<para lang="en">File: <filename>examplewindow.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;iostream&gt;

ExampleWindow::ExampleWindow()
: m_VBox(Gtk::ORIENTATION_VERTICAL),
  m_Button_Close("Close")
{
  set_title("Gtk::Entry");

  add(m_VBox);

  m_Entry.set_max_length(50);
  m_Entry.set_text("Hello world");
  m_VBox.pack_start(m_Entry, Gtk::PACK_SHRINK);

  m_Entry.set_icon_from_icon_name("edit-find");
  m_Entry.signal_icon_press().connect( sigc::mem_fun(*this, &amp;ExampleWindow::on_icon_pressed) );


  m_Button_Close.signal_clicked().connect( sigc::mem_fun(*this,
              &amp;ExampleWindow::on_button_close) );
  m_VBox.pack_start(m_Button_Close, Gtk::PACK_SHRINK);
  m_Button_Close.set_can_default();
  m_Button_Close.grab_default();

  show_all_children();
}

ExampleWindow::~ExampleWindow()
{
}

void ExampleWindow::on_icon_pressed(Gtk::EntryIconPosition /* icon_pos */, const GdkEventButton* /* event */)
{
  std::cout &lt;&lt; "Icon pressed." &lt;&lt; std::endl;
}

void ExampleWindow::on_button_close()
{
  hide();
}

</programlisting>
<!-- end inserted example code -->

</sect3>
</sect2>

<sect2 id="sec-text-entry-progress">
<title>Saisie avec barre de progression</title>
<para>Un élément graphique <classname>Entry</classname> peut afficher une barre de progression dans la zone de saisie du texte, en arrière plan du texte. La barre de progression est affichée en faisant appel aux fonctions membres <methodname>set_progress_fraction()</methodname> ou <methodname>set_progress_pulse_step()</methodname>.</para>

<sect3 id="entry-progress-example"><title>Exemple de saisie avec barre de progression</title>
<para>Cet exemple montre un élément graphique <classname>Gtk::Entry</classname> avec barre de progression.</para>

<figure id="figure-entry-progress">
  <title>Saisie avec barre de progression</title>
  <screenshot>
    <graphic format="PNG" fileref="figures/entry_progress.png"/>
  </screenshot>
</figure>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/entry/progress?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>examplewindow.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLEWINDOW_H
#define GTKMM_EXAMPLEWINDOW_H

#include &lt;gtkmm.h&gt;

class ExampleWindow : public Gtk::Window
{
public:
  ExampleWindow();
  virtual ~ExampleWindow();

protected:
  //Signal handlers:
  bool on_timeout();
  void on_button_close();

  //Child widgets:
  Gtk::Box m_VBox;
  Gtk::Entry m_Entry;
  Gtk::Button m_Button_Close;
};

#endif //GTKMM_EXAMPLEWINDOW_H
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;gtkmm/application.h&gt;

int main(int argc, char *argv[])
{
  auto app = Gtk::Application::create(argc, argv, "org.gtkmm.example");

  ExampleWindow window;

  //Shows the window and returns when it is closed.
  return app-&gt;run(window);
}
</programlisting>
<para lang="en">File: <filename>examplewindow.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;iostream&gt;

ExampleWindow::ExampleWindow()
: m_VBox(Gtk::ORIENTATION_VERTICAL),
  m_Button_Close("Close")
{
  set_title("Gtk::Entry");

  add(m_VBox);

  m_Entry.set_max_length(50);
  m_Entry.set_text("Hello world");
  m_VBox.pack_start(m_Entry, Gtk::PACK_SHRINK);

  //Change the progress fraction every 0.1 second:
  Glib::signal_timeout().connect(
    sigc::mem_fun(*this, &amp;ExampleWindow::on_timeout),
    100
  );

  m_Button_Close.signal_clicked().connect( sigc::mem_fun(*this,
              &amp;ExampleWindow::on_button_close) );
  m_VBox.pack_start(m_Button_Close, Gtk::PACK_SHRINK);
  m_Button_Close.set_can_default();
  m_Button_Close.grab_default();

  show_all_children();
}

ExampleWindow::~ExampleWindow()
{
}

bool ExampleWindow::on_timeout()
{
  static double fraction = 0;
  m_Entry.set_progress_fraction(fraction);

  fraction += 0.01;
  if(fraction &gt; 1)
    fraction = 0;

  return true;
}

void ExampleWindow::on_button_close()
{
  hide();
}

</programlisting>
<!-- end inserted example code -->

</sect3>
</sect2>

</sect1>

<sect1 id="sec-spinbutton">
<title>Bouton compteur</title>

<para lang="en">
A <classname>SpinButton</classname> allows the user to select a value from a
range of numeric values. It has an <classname>Entry</classname> widget with increment and decrement buttons
at the side. Clicking the buttons causes the value to 'spin' up and down across
the range of possible values. The <classname>Entry</classname> widget may also
be used to enter a value directly.
</para>

<para lang="en">
The value can have an adjustable number of decimal places, and the step size is
configurable. <classname>SpinButton</classname>s have an 'auto-repeat' feature
as well: holding down the increment or decrement button can optionally cause the value to
change more quickly the longer the button is held down.
</para>

<para lang="en">
<classname>SpinButton</classname>s use an <link linkend="chapter-adjustment">Adjustment</link> object to hold information about
the range of values. These Adjustment attributes are used by the Spin Button
like so:
<itemizedlist>
<listitem>

<para lang="en">
 <literal>value</literal>: value for the Spin Button
</para>
</listitem>
<listitem>

<para lang="en">
 <literal>lower</literal>: lower range value
</para>
</listitem>
<listitem>

<para lang="en">
 <literal>upper</literal>: upper range value
</para>
</listitem>
<listitem>
<para lang="en">
 <literal>step_increment</literal>: value to increment/decrement when pressing
mouse button 1 on a button
</para>
</listitem>
<listitem>

<para lang="en">
 <literal>page_increment</literal>: value to increment/decrement when pressing
mouse button 2 on a button
</para>
</listitem>
<listitem>

<para lang="en">
 <literal>page_size</literal>: unused
</para>
</listitem>

</itemizedlist>
</para>

<para>De plus, il est possible d'utiliser le bouton 3 de la souris pour sauter directement aux valeurs <literal>upper</literal> ou <literal>lower</literal>.</para>

<para>L'objet <classname>SpinButton</classname> crée un objet <classname>Adjustment</classname> par défaut dont le pointeur est accessible avec la fonction membre <methodname>get_adjustment()</methodname>. Vous pouvez également préciser un objet <classname>Adjustment</classname> existant dans le constructeur.</para>


<sect2 id="spinbutton-methods"><title>Fonctions membres</title>

<para>Le nombre de décimales est modifié à l'aide de la fonction membre <methodname>set_digits()</methodname>.</para>

<para>Il est possible de définir la valeur du compteur avec la fonction membre <methodname>set_value()</methodname> et de la récupérer avec <methodname>get_value()</methodname>.</para>

<para lang="en">
The <methodname>spin()</methodname> method 'spins' the
<classname>SpinButton</classname>, as if its increment or decrement button had been clicked.
You need to specify a <classname>Gtk::SpinType</classname> to specify the
direction or new position.
</para>

<para>Pour empêcher l'utilisateur d'entrer des caractères non-numériques dans le champ de saisie, passez le paramètre <literal>true</literal> à la fonction membre <methodname>set_numeric()</methodname>.</para>

<para>Pour que le <classname>SpinButton</classname> « boucle » de la limite supérieure à la limite inférieure de la plage de valeurs (et inversement), utilisez la fonction membre <methodname>set_wrap()</methodname>.</para>

<para>Pour forcer le <classname>SpinButton</classname> à arrondir sa valeur au <literal>step_increment</literal> (pas d'incrément) le plus proche, utilisez la fonction membre <methodname>set_snap_to_ticks()</methodname>.</para>

<para lang="en"><ulink url="http://developer.gnome.org/gtkmm/3.22/classGtk_1_1SpinButton.html">Reference</ulink></para>

</sect2>

<sect2 id="spinbutton-example"><title>Exemple</title>

<para>Voici un exemple de <classname>SpinButton</classname> en action :</para>

<figure id="figure-spinbutton">
  <title>Bouton compteur</title>
  <screenshot>
    <graphic format="PNG" fileref="figures/spinbutton.png"/>
  </screenshot>
</figure>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/spinbutton?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>examplewindow.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLEWINDOW_H
#define GTKMM_EXAMPLEWINDOW_H

#include &lt;gtkmm.h&gt;

class ExampleWindow : public Gtk::Window
{
public:
  ExampleWindow();
  virtual ~ExampleWindow();

protected:
  //Signal handlers:
  void on_checkbutton_snap();
  void on_checkbutton_numeric();
  void on_spinbutton_digits_changed();
  void on_button_close();

  enum enumValueFormats
  {
    VALUE_FORMAT_INT,
    VALUE_FORMAT_FLOAT
  };
  void on_button_getvalue(enumValueFormats display);

  //Child widgets:
  Gtk::Frame m_Frame_NotAccelerated, m_Frame_Accelerated;
  Gtk::Box m_HBox_NotAccelerated, m_HBox_Accelerated,
    m_HBox_Buttons;
  Gtk::Box m_VBox_Main, m_VBox, m_VBox_Day, m_VBox_Month, m_VBox_Year,
    m_VBox_Accelerated, m_VBox_Value, m_VBox_Digits;
  Gtk::Label m_Label_Day, m_Label_Month, m_Label_Year,
    m_Label_Value, m_Label_Digits,
    m_Label_ShowValue;
  Glib::RefPtr&lt;Gtk::Adjustment&gt; m_adjustment_day, m_adjustment_month, m_adjustment_year,
    m_adjustment_value, m_adjustment_digits;
  Gtk::SpinButton m_SpinButton_Day, m_SpinButton_Month, m_SpinButton_Year,
    m_SpinButton_Value, m_SpinButton_Digits;
  Gtk::CheckButton m_CheckButton_Snap, m_CheckButton_Numeric;
  Gtk::Button m_Button_Int, m_Button_Float, m_Button_Close;
};

#endif //GTKMM_EXAMPLEWINDOW_H
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;gtkmm/application.h&gt;

int main(int argc, char *argv[])
{
  auto app = Gtk::Application::create(argc, argv, "org.gtkmm.example");

  ExampleWindow window;

  //Shows the window and returns when it is closed.
  return app-&gt;run(window);
}
</programlisting>
<para lang="en">File: <filename>examplewindow.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;iostream&gt;
#include &lt;cstdio&gt;

ExampleWindow::ExampleWindow()
:
  m_Frame_NotAccelerated("Not accelerated"),
  m_Frame_Accelerated("Accelerated"),
  m_VBox_Main(Gtk::ORIENTATION_VERTICAL, 5),
  m_VBox(Gtk::ORIENTATION_VERTICAL),
  m_VBox_Day(Gtk::ORIENTATION_VERTICAL),
  m_VBox_Month(Gtk::ORIENTATION_VERTICAL),
  m_VBox_Year(Gtk::ORIENTATION_VERTICAL),
  m_VBox_Accelerated(Gtk::ORIENTATION_VERTICAL),
  m_VBox_Value(Gtk::ORIENTATION_VERTICAL),
  m_VBox_Digits(Gtk::ORIENTATION_VERTICAL),
  m_Label_Day("Day: ", Gtk::ALIGN_START),
  m_Label_Month("Month: ", Gtk::ALIGN_START),
  m_Label_Year("Year: ", Gtk::ALIGN_START),
  m_Label_Value("Value: ", Gtk::ALIGN_START),
  m_Label_Digits("Digits: ", Gtk::ALIGN_START),
  m_adjustment_day( Gtk::Adjustment::create(1.0, 1.0, 31.0, 1.0, 5.0, 0.0) ),
  m_adjustment_month( Gtk::Adjustment::create(1.0, 1.0, 12.0, 1.0, 5.0, 0.0) ),
  m_adjustment_year( Gtk::Adjustment::create(2012.0, 1.0, 2200.0, 1.0, 100.0, 0.0) ),
  m_adjustment_value( Gtk::Adjustment::create(0.0, -10000.0, 10000.0, 0.5, 100.0, 0.0) ),
  m_adjustment_digits( Gtk::Adjustment::create(2.0, 1.0, 5.0, 1.0, 1.0, 0.0) ),
  m_SpinButton_Day(m_adjustment_day),
  m_SpinButton_Month(m_adjustment_month),
  m_SpinButton_Year(m_adjustment_year),
  m_SpinButton_Value(m_adjustment_value, 1.0, 2),
  m_SpinButton_Digits(m_adjustment_digits),
  m_CheckButton_Snap("Snap to 0.5-ticks"),
  m_CheckButton_Numeric("Numeric only input mode"),
  m_Button_Int("Value as Int"),
  m_Button_Float("Value as Float"),
  m_Button_Close("Close")
{
  set_title("SpinButton");

  m_VBox_Main.set_border_width(10);
  add(m_VBox_Main);

  m_VBox_Main.pack_start(m_Frame_NotAccelerated);

  m_VBox.set_border_width(5);
  m_Frame_NotAccelerated.add(m_VBox);

  /* Day, month, year spinners */

  m_VBox.pack_start(m_HBox_NotAccelerated, Gtk::PACK_EXPAND_WIDGET, 5);

  m_VBox_Day.pack_start(m_Label_Day);

  m_SpinButton_Day.set_wrap();

  m_VBox_Day.pack_start(m_SpinButton_Day);

  m_HBox_NotAccelerated.pack_start(m_VBox_Day, Gtk::PACK_EXPAND_WIDGET, 5);

  m_VBox_Month.pack_start(m_Label_Month);

  m_SpinButton_Month.set_wrap();
  m_VBox_Month.pack_start(m_SpinButton_Month);

  m_HBox_NotAccelerated.pack_start(m_VBox_Month, Gtk::PACK_EXPAND_WIDGET, 5);

  m_VBox_Year.pack_start(m_Label_Year);

  m_SpinButton_Year.set_wrap();
  m_SpinButton_Year.set_size_request(55, -1);
  m_VBox_Year.pack_start(m_SpinButton_Year);

  m_HBox_NotAccelerated.pack_start(m_VBox_Year, Gtk::PACK_EXPAND_WIDGET, 5);

  //Accelerated:
  m_VBox_Main.pack_start(m_Frame_Accelerated);

  m_VBox_Accelerated.set_border_width(5);
  m_Frame_Accelerated.add(m_VBox_Accelerated);

  m_VBox_Accelerated.pack_start(m_HBox_Accelerated, Gtk::PACK_EXPAND_WIDGET, 5);

  m_HBox_Accelerated.pack_start(m_VBox_Value, Gtk::PACK_EXPAND_WIDGET, 5);

  m_VBox_Value.pack_start(m_Label_Value);

  m_SpinButton_Value.set_wrap();
  m_SpinButton_Value.set_size_request(100, -1);
  m_VBox_Value.pack_start(m_SpinButton_Value);

  m_HBox_Accelerated.pack_start(m_VBox_Digits, Gtk::PACK_EXPAND_WIDGET, 5);

  m_VBox_Digits.pack_start(m_Label_Digits);

  m_SpinButton_Digits.set_wrap();
  m_adjustment_digits-&gt;signal_value_changed().connect( sigc::mem_fun(*this,
              &amp;ExampleWindow::on_spinbutton_digits_changed) );

  m_VBox_Digits.pack_start(m_SpinButton_Digits);


  //CheckButtons:
  m_VBox_Accelerated.pack_start(m_CheckButton_Snap);
  m_CheckButton_Snap.set_active();
  m_CheckButton_Snap.signal_clicked().connect( sigc::mem_fun(*this,
              &amp;ExampleWindow::on_checkbutton_snap) );

  m_VBox_Accelerated.pack_start(m_CheckButton_Numeric);
  m_CheckButton_Numeric.set_active();
  m_CheckButton_Numeric.signal_clicked().connect( sigc::mem_fun(*this,
              &amp;ExampleWindow::on_checkbutton_numeric) );


  //Buttons:
  m_VBox_Accelerated.pack_start (m_HBox_Buttons, Gtk::PACK_SHRINK, 5);

  m_Button_Int.signal_clicked().connect( sigc::bind( sigc::mem_fun(*this,
                  &amp;ExampleWindow::on_button_getvalue), VALUE_FORMAT_INT) );
  m_HBox_Buttons.pack_start(m_Button_Int, Gtk::PACK_EXPAND_WIDGET, 5);

  m_Button_Float.signal_clicked().connect( sigc::bind( sigc::mem_fun(*this,
                  &amp;ExampleWindow::on_button_getvalue), VALUE_FORMAT_FLOAT) );
  m_HBox_Buttons.pack_start(m_Button_Float, Gtk::PACK_EXPAND_WIDGET, 5);

  m_VBox_Accelerated.pack_start(m_Label_ShowValue);
  m_Label_ShowValue.set_text("0");

  //Close button:
  m_Button_Close.signal_clicked().connect( sigc::mem_fun(*this,
              &amp;ExampleWindow::on_button_close) );
  m_VBox_Main.pack_start(m_Button_Close, Gtk::PACK_SHRINK);

  show_all_children();
}

ExampleWindow::~ExampleWindow()
{
}


void ExampleWindow::on_button_close()
{
  hide();
}

void ExampleWindow::on_checkbutton_snap()
{
  m_SpinButton_Value.set_snap_to_ticks( m_CheckButton_Snap.get_active() );
}

void ExampleWindow::on_checkbutton_numeric()
{
  m_SpinButton_Value.set_numeric( m_CheckButton_Numeric.get_active() );
}

void ExampleWindow::on_spinbutton_digits_changed()
{
  m_SpinButton_Value.set_digits( m_SpinButton_Digits.get_value_as_int() );
}

void ExampleWindow::on_button_getvalue(enumValueFormats display)
{
  gchar buf[32];

  if (display == VALUE_FORMAT_INT)
    sprintf (buf, "%d", m_SpinButton_Value.get_value_as_int());
  else
    sprintf (buf, "%0.*f", m_SpinButton_Value.get_digits(),
            m_SpinButton_Value.get_value());

  m_Label_ShowValue.set_text(buf);
}
</programlisting>
<!-- end inserted example code -->

</sect2>

</sect1>

<sect1 id="sec-progressbar">
<title>Barres de progression</title>

<para>Les barres de progression s'utilisent pour afficher l'avancement d'une opération en cours. Par exemple, un objet <classname>ProgressBar</classname> peut afficher le pourcentage de réalisation d'une tâche.</para>

<para lang="en">
To change the value shown, use the <methodname>set_fraction()</methodname> method,
passing a <type>double</type> between 0.0 and 1.0 to provide the new percentage.
</para>

<para lang="en">
A <classname>ProgressBar</classname> is horizontal and left-to-right by default,
but you can change it to a vertical progress bar by using the
<methodname>set_orientation()</methodname> method.
</para>

<para lang="en"><ulink url="http://developer.gnome.org/gtkmm/3.22/classGtk_1_1ProgressBar.html">Reference</ulink></para>

<sect2 id="progressbar-activity-mode">
<title>Mode activité</title>
<para>Outre l'indication du taux de progression d'une tâche, la barre de progression peut aussi s'utiliser pour indiquer qu'il y a une certaine activité ; cela s'effectue en mettant la barre de progression en <emphasis>mode activité</emphasis>. Dans ce mode, la barre de progression affiche un petit rectangle se déplaçant d'une extrémité à l'autre de la barre. Ce mode est utile dans les cas où le taux de progression d'une opération ne peut pas être calculé sous forme de valeur numérique (par exemple, pour la réception d'un fichier de taille inconnue).</para>

<para>Pour basculer dans ce mode, appelez la fonction membre <methodname>pulse()</methodname> à intervalles réguliers. Vous pourrez aussi choisir la durée des intervalles d'appel avec <methodname>set_pulse_step()</methodname>.</para>

<para lang="en">
The progress bar can also display a configurable text
string within its trough, using the <methodname>set_text()</methodname> method.
</para>
</sect2>

<sect2 id="progressbar-example"><title>Exemple</title>

<figure id="figure-progressbar">
  <title>Barres de progression</title>
  <screenshot>
    <graphic format="PNG" fileref="figures/progressbar.png"/>
  </screenshot>
</figure>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/progressbar?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>examplewindow.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLEWINDOW_H
#define GTKMM_EXAMPLEWINDOW_H

#include &lt;gtkmm.h&gt;

class ExampleWindow : public Gtk::Window
{
public:
  ExampleWindow();
  virtual ~ExampleWindow();

protected:
  //Signal handlers:
  void on_checkbutton_text();
  void on_checkbutton_activity();
  void on_checkbutton_inverted();

  bool on_timeout();
  void on_button_close();

  //Child widgets:
  Gtk::Box m_VBox;
  Gtk::Grid m_Grid;
  Gtk::ProgressBar m_ProgressBar;
  Gtk::Separator m_Separator;
  Gtk::CheckButton m_CheckButton_Text, m_CheckButton_Activity, m_CheckButton_Inverted;
  Gtk::Button m_Button_Close;

  sigc::connection m_connection_timeout;
  bool m_bActivityMode;
};

#endif //GTKMM_EXAMPLEWINDOW_H
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;gtkmm/application.h&gt;

int main(int argc, char *argv[])
{
  auto app = Gtk::Application::create(argc, argv, "org.gtkmm.example");

  ExampleWindow window;

  //Shows the window and returns when it is closed.
  return app-&gt;run(window);
}
</programlisting>
<para lang="en">File: <filename>examplewindow.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;iostream&gt;

ExampleWindow::ExampleWindow()
: m_VBox(Gtk::ORIENTATION_VERTICAL, 5),
  m_CheckButton_Text("Show text"),
  m_CheckButton_Activity("Activity mode"),
  m_CheckButton_Inverted("Right to Left"),
  m_Button_Close("Close"),
  m_bActivityMode(false)
{
  set_resizable();
  set_title("Gtk::ProgressBar");

  m_VBox.set_border_width(10);
  add(m_VBox);

  m_VBox.pack_start(m_ProgressBar, Gtk::PACK_SHRINK, 5);
  m_ProgressBar.set_halign(Gtk::ALIGN_CENTER);
  m_ProgressBar.set_valign(Gtk::ALIGN_CENTER);
  m_ProgressBar.set_text("some text");
  m_ProgressBar.set_show_text(false);

  //Add a timer callback to update the value of the progress bar:
  m_connection_timeout = Glib::signal_timeout().connect(sigc::mem_fun(*this,
              &amp;ExampleWindow::on_timeout), 50 );

  m_VBox.pack_start(m_Separator, Gtk::PACK_SHRINK);
  m_VBox.pack_start(m_Grid);
  m_Grid.set_row_homogeneous(true);

  //Add a check button to select displaying of the trough text:
  m_Grid.attach(m_CheckButton_Text, 0, 0, 1, 1);
  m_CheckButton_Text.property_margin() = 5;
  m_CheckButton_Text.signal_clicked().connect(sigc::mem_fun(*this,
              &amp;ExampleWindow::on_checkbutton_text) );

  //Add a check button to toggle activity mode:
  m_Grid.attach(m_CheckButton_Activity, 0, 1, 1, 1);
  m_CheckButton_Activity.property_margin() = 5;
  m_CheckButton_Activity.signal_clicked().connect(sigc::mem_fun(*this,
              &amp;ExampleWindow::on_checkbutton_activity) );

  //Add a check button to select growth from left to right or from right to left:
  m_Grid.attach(m_CheckButton_Inverted, 0, 2, 1, 1);
  m_CheckButton_Inverted.property_margin() = 5;
  m_CheckButton_Inverted.signal_clicked().connect(sigc::mem_fun(*this,
              &amp;ExampleWindow::on_checkbutton_inverted) );

  //Add a button to exit the program.
  m_VBox.pack_start(m_Button_Close, Gtk::PACK_SHRINK);
  m_Button_Close.signal_clicked().connect(sigc::mem_fun(*this,
              &amp;ExampleWindow::on_button_close) );
  m_Button_Close.set_can_default();
  m_Button_Close.grab_default();

  show_all_children();
}

ExampleWindow::~ExampleWindow()
{
}

void ExampleWindow::on_checkbutton_text()
{
  const bool show_text = m_CheckButton_Text.get_active();
  m_ProgressBar.set_show_text(show_text);
}

void ExampleWindow::on_checkbutton_activity()
{
  m_bActivityMode = m_CheckButton_Activity.get_active();

  if(m_bActivityMode)
    m_ProgressBar.pulse();
  else
    m_ProgressBar.set_fraction(0.0);
}

void ExampleWindow::on_checkbutton_inverted()
{
  const bool inverted = m_CheckButton_Inverted.get_active();
  m_ProgressBar.set_inverted(inverted);
}

void ExampleWindow::on_button_close()
{
  hide();
}

/* Update the value of the progress bar so that we get
 * some movement */
bool ExampleWindow::on_timeout()
{
  if(m_bActivityMode)
    m_ProgressBar.pulse();
  else
  {
    double new_val = m_ProgressBar.get_fraction() + 0.01;

    if(new_val &gt; 1.0)
      new_val = 0.0;

    //Set the new value:
    m_ProgressBar.set_fraction(new_val);
  }

  //As this is a timeout function, return true so that it
  //continues to get called
  return true;
}
</programlisting>
<!-- end inserted example code -->

</sect2>

</sect1>


<sect1 id="sec-infobar">
<title>Infobarre</title>

<para lang="en">
An <classname>InfoBar</classname> may show small items of information or ask brief questions. Unlike a <classname>Dialog</classname>, it appears at the top of the current window instead of opening a new window. Its API is very similar to the <link linkend="chapter-dialogs">Gtk::Dialog</link> API.</para>

<para lang="en"><ulink url="http://developer.gnome.org/gtkmm/3.22/classGtk_1_1InfoBar.html">Reference</ulink></para>

<sect2 id="infobar-example"><title>Exemple</title>

<figure id="figure-infobar">
  <title>Infobarre</title>
  <screenshot>
    <graphic format="PNG" fileref="figures/infobar.png"/>
  </screenshot>
</figure>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/infobar?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>examplewindow.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLEWINDOW_H
#define GTKMM_EXAMPLEWINDOW_H

#include &lt;gtkmm.h&gt;

class ExampleWindow : public Gtk::Window
{
public:
  ExampleWindow();
  virtual ~ExampleWindow();

protected:
  //Signal handlers:
  void on_infobar_response(int response);
  void on_button_quit();
  void on_button_clear();
  void on_textbuffer_changed();

  //Child widgets:
  Gtk::Box m_VBox;

  Gtk::ScrolledWindow m_ScrolledWindow;
  Gtk::TextView m_TextView;

  Glib::RefPtr&lt;Gtk::TextBuffer&gt; m_refTextBuffer;

  Gtk::InfoBar m_InfoBar;
  Gtk::Label m_Message_Label;

  Gtk::ButtonBox m_ButtonBox;
  Gtk::Button m_Button_Quit, m_Button_Clear;
};

#endif //GTKMM_EXAMPLEWINDOW_H
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;gtkmm/application.h&gt;

int main(int argc, char *argv[])
{
  auto app = Gtk::Application::create(argc, argv, "org.gtkmm.example");

  ExampleWindow window;
  //Shows the window and returns when it is closed.
  return app-&gt;run(window);
}
</programlisting>
<para lang="en">File: <filename>examplewindow.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"

ExampleWindow::ExampleWindow()
: m_VBox(Gtk::ORIENTATION_VERTICAL, 6),
  m_Button_Quit("_Quit", true),
  m_Button_Clear("_Clear", true)
{
  set_title("Gtk::InfoBar example");
  set_border_width(6);
  set_default_size(400, 200);

  add(m_VBox);

  // Add the message label to the InfoBar:
  auto infoBarContainer =
    dynamic_cast&lt;Gtk::Container*&gt;(m_InfoBar.get_content_area());
  if (infoBarContainer)
    infoBarContainer-&gt;add(m_Message_Label);

  // Add an ok button to the InfoBar:
  m_InfoBar.add_button("_OK", 0);

  // Add the InfoBar to the vbox:
  m_VBox.pack_start(m_InfoBar, Gtk::PACK_SHRINK);

  // Create the buffer and set it for the TextView:
  m_refTextBuffer = Gtk::TextBuffer::create();
  m_TextView.set_buffer(m_refTextBuffer);

  // Add the TreeView, inside a ScrolledWindow:
  m_ScrolledWindow.add(m_TextView);

  // Show the scrollbars only when they are necessary:
  m_ScrolledWindow.set_policy(Gtk::POLICY_AUTOMATIC, Gtk::POLICY_AUTOMATIC);

  m_VBox.pack_start(m_ScrolledWindow);

  // Add button box:
  m_VBox.pack_start(m_ButtonBox, Gtk::PACK_SHRINK);

  m_ButtonBox.pack_start(m_Button_Clear, Gtk::PACK_SHRINK);
  m_ButtonBox.pack_start(m_Button_Quit, Gtk::PACK_SHRINK);
  m_ButtonBox.set_spacing(6);
  m_ButtonBox.set_layout(Gtk::BUTTONBOX_END);

  // Connect signals:
  m_InfoBar.signal_response().connect(sigc::mem_fun(*this,
              &amp;ExampleWindow::on_infobar_response) );
  m_Button_Quit.signal_clicked().connect(sigc::mem_fun(*this,
              &amp;ExampleWindow::on_button_quit) );
  m_Button_Clear.signal_clicked().connect(sigc::mem_fun(*this,
              &amp;ExampleWindow::on_button_clear) );
  m_refTextBuffer-&gt;signal_changed().connect(sigc::mem_fun(*this,
              &amp;ExampleWindow::on_textbuffer_changed) );

  show_all();

  // Keep the InfoBar hidden until a message needs to be shown:
  m_InfoBar.hide();

  // Make the clear button insensitive until text is typed in the buffer.  When
  // the button is sensitive and it is pressed, the InfoBar is displayed with a
  // message.
  m_Button_Clear.set_sensitive(false);
}

ExampleWindow::~ExampleWindow()
{
}

void ExampleWindow::on_infobar_response(int)
{
  // Clear the message and hide the info bar:
  m_Message_Label.set_text("");
  m_InfoBar.hide();
}

void ExampleWindow::on_button_quit()
{
  hide();
}

void ExampleWindow::on_button_clear()
{
  m_refTextBuffer-&gt;set_text("");
  m_Message_Label.set_text("Cleared the text.");
  m_InfoBar.set_message_type(Gtk::MESSAGE_INFO);
  m_InfoBar.show();
}

void ExampleWindow::on_textbuffer_changed()
{
  m_Button_Clear.set_sensitive(m_refTextBuffer-&gt;size() &gt; 0);
}
</programlisting>
<!-- end inserted example code -->

</sect2>

</sect1>

<sect1 id="sec-tooltips">
<title>Infobulles</title>

<para>L'infobulle est un petite fenêtre informative qui apparaît quand vous laissez votre pointeur de souris sur un élément graphique pendant quelques secondes. Servez-vous de la fonction membre <methodname>set_tooltip_text()</methodname> pour définir une chaîne textuelle d'infobulle sur n'importe quel élément graphique de la classe <classname>Widget</classname>. Les objets <classname>Gtk::ToolItem</classname> ne sont pas des objets de la classe <classname>Widget</classname>, mais disposent des mêmes fonctions membres pour des raisons de commodité. <classname>Gtk::Tooltip</classname> s'utilise pour une utilisation plus sophistiquée des infobulles, comme l'affichage d'images et de texte.</para>

<para lang="en"><ulink url="http://developer.gnome.org/gtkmm/3.22/classGtk_1_1Widget.html">Widget Reference</ulink></para>
<para lang="en"><ulink url="http://developer.gnome.org/gtkmm/3.22/classGtk_1_1Tooltip.html">Tooltip Reference</ulink></para>

<sect2 id="tooltip-example"><title>Exemple</title>

<figure id="figure-tooltip">
  <title>Infobulle</title>
  <screenshot>
    <graphic format="PNG" fileref="figures/tooltip.png"/>
  </screenshot>
</figure>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/tooltips?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>examplewindow.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLEWINDOW_H
#define GTKMM_EXAMPLEWINDOW_H

#include &lt;gtkmm.h&gt;

class ExampleWindow : public Gtk::Window
{
public:

  ExampleWindow();
  virtual ~ExampleWindow();

protected:

  //Methods:
  void prepare_textview();
  void connect_signals();

  //Signal handlers:
  void on_markup_checkbutton_click();
  bool on_textview_query_tooltip(int x, int y, bool keyboard_tooltip, const Glib::RefPtr&lt;Gtk::Tooltip&gt;&amp; tooltip);
  bool on_button_query_tooltip(int x, int y, bool keyboard_tooltip, const Glib::RefPtr&lt;Gtk::Tooltip&gt;&amp; tooltip);

  //Child widgets:
  Gtk::Box m_vbox;

  Gtk::CheckButton m_checkbutton;
  Gtk::Label m_label;

  Gtk::ScrolledWindow m_scrolled_window;
  Gtk::TextView m_text_view;
  Glib::RefPtr&lt;Gtk::TextBuffer&gt; m_ref_text_buffer;
  Glib::RefPtr&lt;Gtk::TextTag&gt; m_ref_bold_tag;

  Gtk::Button m_button;
  Gtk::Window m_button_tooltip_window;

};

#endif // GTKMM_EXAMPLEWINDOW_H

</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;gtkmm/application.h&gt;

int main(int argc, char *argv[])
{
  auto app = Gtk::Application::create(argc, argv, "org.gtkmm.example");

  ExampleWindow window;

  //Shows the window and returns when it is closed.
  return app-&gt;run(window);
}
</programlisting>
<para lang="en">File: <filename>examplewindow.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"

#include &lt;vector&gt;

const Glib::ustring app_title = "gtkmm tooltips example";
const Glib::ustring non_markedup_tip = "A tooltip without markup.";
const Glib::ustring markedup_tip = "&lt;i&gt;Markup&lt;/i&gt; in a tooltip.";

ExampleWindow::ExampleWindow()
  :
  m_vbox(Gtk::ORIENTATION_VERTICAL, 3),
  m_checkbutton("Click to alternate markup in tooltip"),
  m_label("A label"),
  m_button("Custom widget in tooltip window"),
  m_button_tooltip_window(Gtk::WINDOW_POPUP)
{
  //Set up window and the top-level container:
  set_title(app_title);
  set_border_width(10);

  add(m_vbox);

  //Check button with markup in tooltip:
  m_checkbutton.set_tooltip_text(non_markedup_tip);
  m_vbox.pack_start(m_checkbutton, Gtk::PACK_SHRINK);

  //Label:
  m_label.set_tooltip_text("Another tooltip");
  m_vbox.pack_start(m_label, Gtk::PACK_SHRINK);

  //Textview:
  prepare_textview();

  //Button:
  // set_tooltip_window(), like set_tooltip_text(),
  // will call set_has_tooltip() for us.
  m_button.set_tooltip_window(m_button_tooltip_window);
  m_vbox.pack_start(m_button, Gtk::PACK_SHRINK);

  //Button's custom tooltip window:
  m_button_tooltip_window.set_default_size(250, 30);
  Gtk::Label* label =
    Gtk::manage(new Gtk::Label("A label in a custom tooltip window"));
  label-&gt;show();
  m_button_tooltip_window.add(*label);

  connect_signals();

  show_all_children();
}

ExampleWindow::~ExampleWindow()
{
}

void ExampleWindow::prepare_textview()
{
  Gtk::TextIter iter;
  std::vector&lt; Glib::RefPtr&lt;Gtk::TextTag&gt; &gt; tags;

  //Set up a scrolled window:
  m_scrolled_window.add(m_text_view);
  m_scrolled_window.set_policy(Gtk::POLICY_AUTOMATIC, Gtk::POLICY_AUTOMATIC);
  m_vbox.pack_start(m_scrolled_window);

  //Create a text buffer with some text:
  m_ref_text_buffer = Gtk::TextBuffer::create();

  iter = m_ref_text_buffer-&gt;end();
  m_ref_text_buffer-&gt;insert(iter, "Hover over the text ");

  //Insert some text with a tag.
  //In the tooltip signal handler below, we will show a tooltip
  //when mouse pointer is above this tagged text.
  m_ref_bold_tag = m_ref_text_buffer-&gt;create_tag("bold");
  m_ref_bold_tag-&gt;set_property("weight", Pango::WEIGHT_BOLD);

  tags.push_back(m_ref_bold_tag);

  iter = m_ref_text_buffer-&gt;end();
  m_ref_text_buffer-&gt;insert_with_tags(iter, "in bold", tags);

  iter = m_ref_text_buffer-&gt;end();
  m_ref_text_buffer-&gt;insert(iter, " to see its tooltip");

  m_text_view.set_buffer(m_ref_text_buffer);

  m_text_view.set_size_request(320, 50);

  //When only connecting to the query-tooltip signal, and not using any
  //of set_tooltip_text(), set_tooltip_markup() or set_tooltip_window(),
  //we need to explicitly tell GTK+ that the widget has a tooltip which
  //we'll show.
  m_text_view.set_has_tooltip();
}

void ExampleWindow::connect_signals()
{
  m_checkbutton.signal_clicked().connect(
    sigc::mem_fun(*this, &amp;ExampleWindow::on_markup_checkbutton_click));

  m_text_view.signal_query_tooltip().connect(
    sigc::mem_fun(*this, &amp;ExampleWindow::on_textview_query_tooltip));

  m_button.signal_query_tooltip().connect(
    sigc::mem_fun(*this, &amp;ExampleWindow::on_button_query_tooltip));
}

void ExampleWindow::on_markup_checkbutton_click()
{
  if (m_checkbutton.get_active() == true)
  {
    m_checkbutton.set_tooltip_markup(markedup_tip);
  }
  else
  {
    m_checkbutton.set_tooltip_markup(non_markedup_tip);
  }
}

bool ExampleWindow::on_textview_query_tooltip(int x, int y, bool keyboard_tooltip, const Glib::RefPtr&lt;Gtk::Tooltip&gt;&amp; tooltip)
{
  Gtk::TextIter iter;

  if (keyboard_tooltip)
  {
    int offset = m_ref_text_buffer-&gt;property_cursor_position().get_value();
    iter = m_ref_text_buffer-&gt;get_iter_at_offset(offset);
  }
  else
  {
    int mouse_x, mouse_y, trailing;
    m_text_view.window_to_buffer_coords(Gtk::TEXT_WINDOW_TEXT,
                                        x, y, mouse_x, mouse_y);
    m_text_view.get_iter_at_position(iter, trailing, mouse_x, mouse_y);
  }

  //Show a tooltip if the cursor or mouse pointer is over the text
  //with the specific tag:
  if (iter.has_tag(m_ref_bold_tag))
  {
    tooltip-&gt;set_markup("&lt;b&gt;Information&lt;/b&gt; attached to a text tag");
    tooltip-&gt;set_icon_from_icon_name("dialog-information", Gtk::ICON_SIZE_MENU);
  }
  else
  {
    return false;
  }

  return true;
}

bool ExampleWindow::on_button_query_tooltip(int, int, bool, const Glib::RefPtr&lt;Gtk::Tooltip&gt;&amp;)
{
  //We already have a custom window ready, just return true to show it:
  return true;
}
</programlisting>
<!-- end inserted example code -->

</sect2>

</sect1>

</chapter>

<chapter id="chapter-container-widgets">
<title>Éléments graphiques conteneurs</title>

<para lang="en">
All container widgets derive from <classname>Gtk::Container</classname>, not
always directly. Some container widgets, such as
<classname>Gtk::Grid</classname> can hold many child widgets, so these
typically have more complex interfaces. Others, such as
<classname>Gtk::Frame</classname> contain only one child widget.
</para>

<sect1 id="sec-single-item-containers">
<title>Conteneurs mono-éléments</title>

<para>Les éléments conteneurs mono-éléments dérivent de la classe <classname>Gtk::Bin</classname> ; cette classe comporte les fonctions membres <methodname>add()</methodname> et <methodname>remove()</methodname> pour les éléments graphiques enfants. Notez que les objets de la classe <classname>Gtk::Button</classname> et <classname>Gtk::Window</classname> sont techniquement des conteneurs mono-éléments ; nous l'avons déjà signalé par ailleurs.</para>

<para>Nous évoquerons également l'élément graphique <classname>Gtk::Paned</classname> qui vous permet de partager une fenêtre en deux « volets » séparés. Cet élément graphique comporte en réalité deux éléments graphiques enfants, mais comme ce nombre est fixe, son classement dans les mono-éléments paraît approprié.</para>

<sect2 id="sec-frame">
<title>Cadre</title>

<para>Les cadres, avec un intitulé en option, peuvent entourer un ou un groupe d'éléments graphiques dans une boîte. Par exemple, vous pouvez placer un groupe de <classname>RadioButton</classname> ou de <classname>CheckButton</classname> dans un objet <classname>Frame</classname>.</para>

<para lang="en"><ulink url="http://developer.gnome.org/gtkmm/3.22/classGtk_1_1Frame.html">Reference</ulink></para>

<sect3 id="frame-example"><title>Exemple</title>

<figure id="figure-frame">
  <title>Cadre</title>
  <screenshot>
    <graphic format="PNG" fileref="figures/frame.png"/>
  </screenshot>
</figure>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/frame?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>examplewindow.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLEWINDOW_H
#define GTKMM_EXAMPLEWINDOW_H

#include &lt;gtkmm.h&gt;

class ExampleWindow : public Gtk::Window
{
public:
  ExampleWindow();
  virtual ~ExampleWindow();

protected:

  //Child widgets:
  Gtk::Frame m_Frame;
};

#endif //GTKMM_EXAMPLEWINDOW_H
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;gtkmm/application.h&gt;

int main(int argc, char *argv[])
{
  auto app = Gtk::Application::create(argc, argv, "org.gtkmm.example");

  ExampleWindow window;

  //Shows the window and returns when it is closed.
  return app-&gt;run(window);
}
</programlisting>
<para lang="en">File: <filename>examplewindow.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"

ExampleWindow::ExampleWindow()
{
 /* Set some window properties */
  set_title("Frame Example");
  set_size_request(300, 300);

  /* Sets the border width of the window. */
  set_border_width(10);

  add(m_Frame);

  /* Set the frames label */
  m_Frame.set_label("Gtk::Frame Widget");

  /* Align the label at the right of the frame */
  //m_Frame.set_label_align(Gtk::ALIGN_END, Gtk::ALIGN_START);

  /* Set the style of the frame */
  m_Frame.set_shadow_type(Gtk::SHADOW_ETCHED_OUT);

  show_all_children();
}

ExampleWindow::~ExampleWindow()
{
}

</programlisting>
<!-- end inserted example code -->

</sect3>

</sect2>


<sect2 id="sec-paned">
<title>Volets</title>

<para lang="en">
Panes divide a widget into two halves, separated by a moveable divider.
The two halves (panes) can be oriented either horizontally (side by side) or
vertically (one above the other).
</para>

<para lang="en">
Unlike the other widgets in this section, pane widgets contain not one but two
child widgets, one in each pane. Therefore, you should use
<methodname>add1()</methodname> and <methodname>add2()</methodname> instead of the
<methodname>add()</methodname> method.
</para>

<para>Il est possible d'ajuster la position de la division avec la fonction membre <methodname>set_position()</methodname> ; vous aurez certainement besoin de le faire.</para>

<para lang="en"><ulink url="http://developer.gnome.org/gtkmm/3.22/classGtk_1_1Paned.html">Reference</ulink></para>

<sect3 id="paned-example"><title>Exemple</title>

<figure id="figure-paned">
  <title>Volets</title>
  <screenshot>
    <graphic format="PNG" fileref="figures/paned.png"/>
  </screenshot>
</figure>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/paned?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>messageslist.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLE_MESSAGESLIST_H
#define GTKMM_EXAMPLE_MESSAGESLIST_H

#include &lt;gtkmm.h&gt;

class MessagesList: public Gtk::ScrolledWindow
{
public:
  MessagesList();
  virtual ~MessagesList();

  class ModelColumns : public Gtk::TreeModel::ColumnRecord
  {
  public:

    ModelColumns()
    { add(m_col_text); }

    Gtk::TreeModelColumn&lt;Glib::ustring&gt; m_col_text;
  };

  ModelColumns m_Columns;

protected:
  Glib::RefPtr&lt;Gtk::ListStore&gt; m_refListStore; //The Tree Model.
  Gtk::TreeView m_TreeView; //The Tree View.
};
#endif //GTKMM_EXAMPLE_MESSAGESLIST_H
</programlisting>
<para lang="en">File: <filename>examplewindow.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLEWINDOW_H
#define GTKMM_EXAMPLEWINDOW_H

#include "messageslist.h"
#include "messagetext.h"
#include &lt;gtkmm.h&gt;

class ExampleWindow : public Gtk::Window
{
public:
  ExampleWindow();
  virtual ~ExampleWindow();

protected:

  //Child widgets:
  Gtk::Paned m_VPaned;
  MessagesList m_MessagesList;
  MessageText m_MessageText;
};

#endif //GTKMM_EXAMPLEWINDOW_H
</programlisting>
<para lang="en">File: <filename>messagetext.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLE_MESSAGETEXT_H
#define GTKMM_EXAMPLE_MESSAGETEXT_H

#include &lt;gtkmm.h&gt;

class MessageText : public Gtk::ScrolledWindow
{
public:
  MessageText();
  virtual ~MessageText();

  void insert_text();

protected:
  Gtk::TextView m_TextView;
};

#endif //GTKMM_EXAMPLE_MESSAGETEXT_H
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;gtkmm/application.h&gt;

int main(int argc, char *argv[])
{
  auto app = Gtk::Application::create(argc, argv, "org.gtkmm.example");

  ExampleWindow window;

  //Shows the window and returns when it is closed.
  return app-&gt;run(window);
}
</programlisting>
<para lang="en">File: <filename>messageslist.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "messageslist.h"
#include &lt;sstream&gt;

MessagesList::MessagesList()
{
  /* Create a new scrolled window, with scrollbars only if needed */
  set_policy(Gtk::POLICY_AUTOMATIC, Gtk::POLICY_AUTOMATIC);

  add(m_TreeView);

  /* create list store */
  m_refListStore = Gtk::ListStore::create(m_Columns);

  m_TreeView.set_model(m_refListStore);

  /* Add some messages to the window */
  for(int i = 0; i &lt; 10; ++i)
  {
    std::ostringstream text;
    text &lt;&lt; "message #" &lt;&lt; i;

    Gtk::TreeModel::Row row = *(m_refListStore-&gt;append());
    row[m_Columns.m_col_text] = text.str();
  }

  //Add the Model's column to the View's columns:
  m_TreeView.append_column("Messages", m_Columns.m_col_text);

  show_all_children();
}

MessagesList::~MessagesList()
{
}
</programlisting>
<para lang="en">File: <filename>examplewindow.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"

ExampleWindow::ExampleWindow()
: m_VPaned(Gtk::ORIENTATION_VERTICAL)
{
  set_title ("Paned Windows");
  set_border_width(10);
  set_default_size(450, 400);

  /* Add a vpaned widget to our toplevel window */
  add(m_VPaned);

  /* Now add the contents of the two halves of the window */
  m_VPaned.add1(m_MessagesList);
  m_VPaned.add2(m_MessageText);

  show_all_children();
}

ExampleWindow::~ExampleWindow()
{
}
</programlisting>
<para lang="en">File: <filename>messagetext.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "messagetext.h"

MessageText::MessageText()
{
  set_policy(Gtk::POLICY_AUTOMATIC, Gtk::POLICY_AUTOMATIC);

  add(m_TextView);
  insert_text();

  show_all_children();
}

MessageText::~MessageText()
{
}

void MessageText::insert_text()
{
  auto refTextBuffer = m_TextView.get_buffer();

  Gtk::TextBuffer::iterator iter = refTextBuffer-&gt;get_iter_at_offset(0);
  refTextBuffer-&gt;insert(iter,
    "From: pathfinder@nasa.gov\n"
    "To: mom@nasa.gov\n"
    "Subject: Made it!\n"
    "\n"
    "We just got in this morning. The weather has been\n"
    "great - clear but cold, and there are lots of fun sights.\n"
    "Sojourner says hi. See you soon.\n"
    " -Path\n");
}
</programlisting>
<!-- end inserted example code -->

</sect3>

</sect2>

<sect2 id="sec-scrolledwindow">
<title>Fenêtre à défilement</title>

<para>Les éléments graphiques <classname>ScrolledWindow</classname> créent une zone qu'il est possible de faire défiler. Vous pouvez insérer n'importe quel type d'élément graphique dans une fenêtre de la classe <classname>ScrolledWindow</classname> ; cet élément graphique restera totalement accessible quelle que soit sa taille grâce aux barres de défilement. Notez que la classe <classname>ScrolledWindow</classname> ne dérive pas de la classe <classname>Gtk::Window</classname>, même si les dénominations peuvent prêter à confusion.</para>

<para>La fenêtre déroulante définit une <emphasis>politique de barres de défilement</emphasis> pour indiquer comment son objet <classname>Scrollbar</classname> doit être affiché. Cette politique est définie à l'aide de la fonction membre <methodname>set_policy()</methodname>. Le paramètre <literal>policy</literal> prend l'une des deux valeurs suivantes : <literal>Gtk::POLICY_AUTOMATIC</literal> ou bien <literal>Gtk::POLICY_ALWAYS</literal>. <literal>Gtk::POLICY_AUTOMATIC</literal> déclenche l'affichage de la barre de défilement uniquement si l'élément graphique incorporé est plus grand que la zone visible. Avec <literal>Gtk::POLICY_ALWAYS</literal>, les barres de défilement sont toujours affichées.</para>

<para lang="en"><ulink url="http://developer.gnome.org/gtkmm/3.22/classGtk_1_1ScrolledWindow.html">Reference</ulink></para>

<sect3 id="scrolledwindow-example"><title>Exemple</title>

<para>Voici un exemple simple qui place 100 boutons bascules dans une fenêtre à défilement. Essayez de redimensionner la fenêtre pour voir comment les barres de défilement réagissent.</para>

<figure id="figure-scrolledwindow">
  <title>Fenêtre à défilement</title>
  <screenshot>
    <graphic format="PNG" fileref="figures/scrolledwindow.png"/>
  </screenshot>
</figure>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/scrolledwindow?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>examplewindow.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLEWINDOW_H
#define GTKMM_EXAMPLEWINDOW_H

#include &lt;gtkmm.h&gt;

class ExampleWindow : public Gtk::Dialog
{
public:
  ExampleWindow();
  virtual ~ExampleWindow();

protected:
  //Signal handlers:
  void on_dialog_response(int response_id);

  //Child widgets:
  Gtk::ScrolledWindow m_ScrolledWindow;
  Gtk::Grid m_Grid;
};

#endif //GTKMM_EXAMPLEWINDOW_H
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;gtkmm/application.h&gt;

int main(int argc, char *argv[])
{
  auto app = Gtk::Application::create(argc, argv, "org.gtkmm.example");

  ExampleWindow window;

  //Shows the window and returns when it is closed.
  return app-&gt;run(window);
}
</programlisting>
<para lang="en">File: <filename>examplewindow.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;iostream&gt;

ExampleWindow::ExampleWindow()
{
  set_title("Gtk::ScrolledWindow example");
  set_border_width(0);
  set_size_request(300, 300);

  m_ScrolledWindow.set_border_width(10);

  /* the policy is one of Gtk::POLICY AUTOMATIC, or Gtk::POLICY_ALWAYS.
   * Gtk::POLICY_AUTOMATIC will automatically decide whether you need
   * scrollbars, whereas Gtk::POLICY_ALWAYS will always leave the scrollbars
   * there.  The first one is the horizontal scrollbar, the second,
   * the vertical. */
  m_ScrolledWindow.set_policy(Gtk::POLICY_AUTOMATIC, Gtk::POLICY_ALWAYS);

  get_content_area()-&gt;pack_start(m_ScrolledWindow);

  /* set the spacing to 10 on x and 10 on y */
  m_Grid.set_row_spacing(10);
  m_Grid.set_column_spacing(10);

  /* pack the grid into the scrolled window */
  m_ScrolledWindow.add(m_Grid);

  /* this simply creates a grid of toggle buttons
   * to demonstrate the scrolled window. */
  for(int i = 0; i &lt; 10; i++)
  {
     for(int j = 0; j &lt; 10; j++)
     {
        char buffer[32];
        sprintf(buffer, "button (%d,%d)\n", i, j);
        auto pButton = Gtk::manage(new Gtk::ToggleButton(buffer));
        m_Grid.attach(*pButton, i, j, 1, 1);
     }
  }

  /* Add a "close" button to the bottom of the dialog */
  add_button("_Close", Gtk::RESPONSE_CLOSE);
  signal_response().connect(sigc::mem_fun(*this, &amp;ExampleWindow::on_dialog_response));

  /* This makes it so the button is the default.
   * Simply hitting the "Enter" key will cause this button to activate. */
  set_default_response(Gtk::RESPONSE_CLOSE);

  show_all_children();
}

ExampleWindow::~ExampleWindow()
{
}

void ExampleWindow::on_dialog_response(int response_id)
{
  switch (response_id)
  {
  case Gtk::RESPONSE_CLOSE:
  case Gtk::RESPONSE_DELETE_EVENT:
    hide();
    break;
  default:
    std::cout &lt;&lt; "Unexpected response_id=" &lt;&lt; response_id &lt;&lt; std::endl;
    break;
  }
}
</programlisting>
<!-- end inserted example code -->

</sect3>

</sect2>

<sect2 id="sec-aspectframe">
<title>Cadre proportionné</title>

<para>L'élément graphique de la classe <classname>AspectFrame</classname> est semblable à l'élément graphique <classname>Frame</classname>, mais, en plus, il impose à l'élément graphique enfant de garder un rapport de <emphasis>proportion</emphasis> (rapport de la largeur à la hauteur) constant ; il laisse un espace libre si nécessaire. Par exemple, vous pourrez afficher une photographie sans que l'utilisateur puisse la déformer horizontalement ou verticalement lorsqu'il la redimensionne.</para>

<para lang="en"><ulink url="http://developer.gnome.org/gtkmm/3.22/classGtk_1_1AspectFrame.html">Reference</ulink></para>

<sect3 id="aspectframe-example">
<title>Exemple</title>
<para>Le programme suivant utilise un objet <classname>Gtk::AspectFrame</classname> pour afficher une surface de tracé dont les proportions sont toujours égales à 2:1 quelles que soient les dimensions données à la fenêtre principale par l'utilisateur.</para>

<figure id="figure-aspectframe">
  <title>Cadre proportionné</title>
  <screenshot>
    <graphic format="PNG" fileref="figures/aspectframe.png"/>
  </screenshot>
</figure>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/aspectframe?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>examplewindow.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLEWINDOW_H
#define GTKMM_EXAMPLEWINDOW_H

#include &lt;gtkmm.h&gt;

class ExampleWindow : public Gtk::Window
{
public:
  ExampleWindow();
  virtual ~ExampleWindow();

protected:

  //Child widgets:
  Gtk::AspectFrame m_AspectFrame;
  Gtk::DrawingArea m_DrawingArea;
};

#endif //GTKMM_EXAMPLEWINDOW_H
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;gtkmm/application.h&gt;

int main(int argc, char *argv[])
{
  auto app = Gtk::Application::create(argc, argv, "org.gtkmm.example");

  ExampleWindow window;

  //Shows the window and returns when it is closed.
  return app-&gt;run(window);
}
</programlisting>
<para lang="en">File: <filename>examplewindow.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"

ExampleWindow::ExampleWindow()
: m_AspectFrame("2x1", /* label */
    Gtk::ALIGN_CENTER, /* center x */
    Gtk::ALIGN_CENTER, /* center y */
    2.0, /* xsize/ysize = 2 */
    false /* ignore child's aspect */)
{
  set_title("Aspect Frame");
  set_border_width(10);

  // Add a child widget to the aspect frame */
  // Ask for a 200x200 window, but the AspectFrame will give us a 200x100
  // window since we are forcing a 2x1 aspect ratio */
  m_DrawingArea.set_size_request(200, 200);
  m_AspectFrame.add(m_DrawingArea);

  // Add the aspect frame to our toplevel window:
  add(m_AspectFrame);

  show_all_children();
}

ExampleWindow::~ExampleWindow()
{
}

</programlisting>
<!-- end inserted example code -->
</sect3>

</sect2>


<sect2 id="sec-alignment">
<title>Alignement</title>

<para>L'élément conteneur <classname>Alignment</classname> vous permet de placer dans une fenêtre un élément graphique dont la taille et la position sont mesurés en rapport de celle du conteneur <classname>Alignment</classname> lui-même. Par exemple, vous pourrez l'utiliser pour centrer un contrôle.</para>

<para lang="en">
The <classname>Alignment</classname> widget is deprecated from <application>gtkmm</application> version 3.14
and should not be used in newly-written code. Use <classname>Gtk::Widget</classname>'s
alignment and margin methods instead.
</para>

<sect3 id="alignment-example">
<title>Exemple</title>
<para lang="en">
This example right-aligns a button in a window by using
<methodname>Gtk::Widget::set_halign()</methodname>.
</para>

<figure id="figure-alignment">
  <title>Alignement</title>
  <screenshot>
    <graphic format="PNG" fileref="figures/alignment.png"/>
  </screenshot>
</figure>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/alignment?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>examplewindow.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLEWINDOW_H
#define GTKMM_EXAMPLEWINDOW_H

#include &lt;gtkmm.h&gt;

class ExampleWindow : public Gtk::Window
{
public:
  ExampleWindow();
  virtual ~ExampleWindow();

protected:
  //Signal handlers:
  void on_button_clicked();

  //Child widgets:
  Gtk::Button m_Button;
};

#endif //GTKMM_EXAMPLEWINDOW_H
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;gtkmm/application.h&gt;

int main(int argc, char *argv[])
{
  auto app = Gtk::Application::create(argc, argv, "org.gtkmm.example");

  ExampleWindow window;

  //Shows the window and returns when it is closed.
  return app-&gt;run(window);
}
</programlisting>
<para lang="en">File: <filename>examplewindow.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"

ExampleWindow::ExampleWindow()
: m_Button("_Close", /* mnemonic= */ true)
{
  set_title("Alignment");
  set_border_width(10);
  set_default_size(200, 50);

  m_Button.set_halign(Gtk::ALIGN_END);
  m_Button.set_valign(Gtk::ALIGN_CENTER);
  add(m_Button);

  m_Button.signal_clicked().connect( sigc::mem_fun(*this,
              &amp;ExampleWindow::on_button_clicked) );

  show_all_children();
}

ExampleWindow::~ExampleWindow()
{
}

void ExampleWindow::on_button_clicked()
{
  hide();
}

</programlisting>
<!-- end inserted example code -->

<para lang="en">
See the <link linkend="sec-progressbar">ProgressBar</link> section for another
example that uses <methodname>set_halign()</methodname>.
</para>

</sect3>

</sect2>

</sect1>

<sect1 id="sec-multi-item-containers">
<title>Conteneurs multi-éléments</title>

<para>Les éléments graphiques conteneurs multi-éléments héritent de la classe <classname>Gtk::Container</classname> ; comme avec <classname>Gtk::Bin</classname>, vous utilisez les fonctions membres <methodname>add()</methodname> et <methodname>remove()</methodname> pour ajouter ou supprimer des éléments graphiques du conteneur. Mais, contrairement à <methodname>Gtk::Bin::remove()</methodname>, la fonction membre <methodname>remove()</methodname> de la classe <classname>Gtk::Container</classname> exige un paramètre désignant l'élément graphique à enlever.</para>

<sect2 id="container-packing">
<title>Empaquetage</title>
<para>Vous avez probablement remarqué que les fenêtres <application>gtkmm</application> semblent « élastiques » — elles peuvent être étirées de diverses manières. Cette propriété résulte du système « d'empaquetage des éléments graphiques ».</para>

<para>Beaucoup de boîtes à outils GUI exigent que les éléments graphiques soient placés avec précision dans une fenêtre, avec un positionnement absolu, souvent en utilisant un utilitaire visuel. Plusieurs problèmes en découlent :</para>

<itemizedlist>

<listitem>
<para>Les éléments graphiques ne se réarrangent pas par eux-mêmes quand la fenêtre est redimensionnée. Certains éléments graphiques sont masqués quand la fenêtre est rapetissée et des espaces libres inutiles apparaissent quand la fenêtre est agrandie.</para>
</listitem>

<listitem>
<para>Il n'est pas possible de prévoir l'espace nécessaire à un texte après traduction en d'autres langues ou après affichage avec une police différente. Sur Unix, il est également impossible d'anticiper les effets de chaque thème ou de chaque gestionnaire de fenêtres.</para>
</listitem>

<listitem>
<para>Modifier la disposition d'une fenêtre « à la volée », pour faire apparaître quelques éléments graphiques supplémentaires, par exemple, est compliqué. Cela demande un nouveau calcul ennuyeux de la position de chaque élément graphique.</para>
</listitem>

</itemizedlist>

<para lang="en">
<application>gtkmm</application> uses the packing system to solve these problems. Rather than specifying the position and size of each widget in the window,
you can arrange your widgets in rows, columns,
and/or grids. <application>gtkmm</application> can size your window automatically, based on the
sizes of the widgets it contains. And the sizes of the widgets are, in turn, determined by the amount of text they contain, or the minimum and maximum sizes that you specify, and/or how you have requested that the available space should be shared between sets of widgets.
You can perfect your layout by
specifying padding distance and centering values for each of your widgets. <application>gtkmm</application> then uses
all this information to resize and reposition everything sensibly and smoothly when the user manipulates the window. </para>

<para><application>gtkmm</application> dispose les éléments graphiques de manière hiérarchique en utilisant des <emphasis>conteneurs</emphasis>. Un élément graphique conteneur contient d'autres éléments graphiques. La plupart des éléments graphiques <application>gtkmm</application> sont des conteneurs. Fenêtres, onglets de bloc-notes et boutons sont tous des éléments graphiques conteneurs. Il existe deux sortes de conteneurs : les conteneurs mono-enfant, qui dérivent tous de la classe <classname>Gtk::Bin</classname> et les conteneurs multi-enfants qui héritent de la classe <classname>Gtk::Container</classname>. La plupart des éléments graphiques de <application>gtkmm</application> dérivent de la classe <classname>Gtk::Bin</classname>, y compris <classname>Gtk::Window</classname>.</para>

<para lang="en">
Yes, that's correct: a Window can contain at most one widget. How, then, can
we use a window for anything useful?  By placing a multiple-child container in
the window. The most useful container widgets are
<classname>Gtk::Grid</classname> and <classname>Gtk::Box</classname>.
</para>


<itemizedlist>

<listitem>
<para><classname>Gtk::Grid</classname> disposent respectivement leurs éléments graphiques enfants en lignes et en colonnes. Utilisez <methodname>attach()</methodname>, <methodname>attach_next_to()</methodname> et <methodname>add()</methodname> pour insérer des éléments graphiques enfants.</para>
</listitem>

<listitem>
<para lang="en">
<classname>Gtk::Box</classname> arranges its child widgets vertically or horizontally. Use
<methodname>pack_start()</methodname> and <methodname>pack_end()</methodname> to insert
child widgets.
</para>
</listitem>

</itemizedlist>

<para>Il existe plusieurs autres conteneurs. Nous en parlerons également.</para>

<para>Si vous n'avez jamais utilisé auparavant un utilitaire d'empaquetage, son utilisation nécessitera une prise en main. Toutefois, vous constaterez probablement que, contrairement à d'autres boîtes à outils, il n'y a pas besoin de faire appel à un éditeur de type visuel.</para>

</sect2>

<sect2 id="sec-helloworld2">
<title>Un Hello World amélioré</title>

<para>Regardons un <literal>helloworld</literal> légèrement perfectionné en se servant de nos nouvelles connaissances.</para>

<figure id="figure-helloworld2">
  <title>Hello World 2</title>
  <screenshot>
    <graphic format="PNG" fileref="figures/helloworld2.png"/>
  </screenshot>
</figure>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/helloworld2?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>helloworld.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLE_HELLOWORLD_H
#define GTKMM_EXAMPLE_HELLOWORLD_H

#include &lt;gtkmm/box.h&gt;
#include &lt;gtkmm/button.h&gt;
#include &lt;gtkmm/window.h&gt;

class HelloWorld : public Gtk::Window
{
public:
  HelloWorld();
  virtual ~HelloWorld();

protected:

  // Signal handlers:
  // Our new improved on_button_clicked(). (see below)
  void on_button_clicked(Glib::ustring data);

  // Child widgets:
  Gtk::Box m_box1;
  Gtk::Button m_button1, m_button2;
};

#endif // GTKMM_EXAMPLE_HELLOWORLD_H
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "helloworld.h"
#include &lt;gtkmm/application.h&gt;

int main (int argc, char *argv[])
{
  auto app = Gtk::Application::create(argc, argv, "org.gtkmm.example");

  HelloWorld helloworld;

  //Shows the window and returns when it is closed.
  return app-&gt;run(helloworld);
}
</programlisting>
<para lang="en">File: <filename>helloworld.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "helloworld.h"
#include &lt;iostream&gt;

HelloWorld::HelloWorld()
: m_button1("Button 1"),
  m_button2("Button 2")
{
  // This just sets the title of our new window.
  set_title("Hello Buttons!");

  // sets the border width of the window.
  set_border_width(10);

  // put the box into the main window.
  add(m_box1);

  // Now when the button is clicked, we call the "on_button_clicked" function
  // with a pointer to "button 1" as it's argument
  m_button1.signal_clicked().connect(sigc::bind&lt;Glib::ustring&gt;(
              sigc::mem_fun(*this, &amp;HelloWorld::on_button_clicked), "button 1"));

  // instead of gtk_container_add, we pack this button into the invisible
  // box, which has been packed into the window.
  // note that the pack_start default arguments are Gtk::EXPAND | Gtk::FILL, 0
  m_box1.pack_start(m_button1);

  // always remember this step, this tells GTK that our preparation
  // for this button is complete, and it can be displayed now.
  m_button1.show();

  // call the same signal handler with a different argument,
  // passing a pointer to "button 2" instead.
  m_button2.signal_clicked().connect(sigc::bind&lt;-1, Glib::ustring&gt;(
              sigc::mem_fun(*this, &amp;HelloWorld::on_button_clicked), "button 2"));

  m_box1.pack_start(m_button2);

  // Show the widgets.
  // They will not really be shown until this Window is shown.
  m_button2.show();
  m_box1.show();
}

HelloWorld::~HelloWorld()
{
}

// Our new improved signal handler.  The data passed to this method is
// printed to stdout.
void HelloWorld::on_button_clicked(Glib::ustring data)
{
  std::cout &lt;&lt; "Hello World - " &lt;&lt; data &lt;&lt; " was pressed" &lt;&lt; std::endl;
}

</programlisting>
<!-- end inserted example code -->

<para>Après avoir construit et lancé ce programme, essayez de redimensionner la fenêtre pour voir son comportement. Également, essayez de jouer avec les options de la fonction membre <methodname>pack_start()</methodname> après avoir lu le paragraphe relatif aux <link linkend="sec-boxes">boîtes</link>.</para>

</sect2>

<sect2 id="sec-boxes">
<title>Boîtes</title>

<para>Beaucoup d'empaquetages utilisent des boîtes comme dans l'exemple précédent. Ce sont des conteneurs invisibles dans lesquels nous pouvons placer les éléments graphiques. Si nous empaquetons dans une boîte horizontale, les objets seront insérés horizontalement de la gauche vers la droite ou inversement selon que l'on utilise <methodname>pack_start()</methodname> ou <methodname>pack_end()</methodname>. Dans une boîte verticale, les éléments graphiques sont empaquetés du haut vers le bas ou vice versa. Vous pouvez utiliser toute combinaison de boîtes dans ou à côté d'autres boîtes pour créer les effets voulus.</para>

<sect3 id="boxes-adding-widgets"><title>Ajout d'éléments graphiques</title>
<sect4 id="per-child-packing-options"><title>Options d'empaquetage par enfant</title>
<para lang="en">
The <methodname>pack_start()</methodname> and
<methodname>pack_end()</methodname> methods place widgets inside these
containers. The <methodname>pack_start()</methodname> method will start at
the top and work its way down in a <classname>Box</classname> with vertical
orientation, or pack left to right in a <classname>Box</classname> with horizontal
orientation. <methodname>pack_end()</methodname> will do the opposite, packing from
bottom to top or from right to left. Using these methods allows us to right justify or
left justify our widgets. We will use <methodname>pack_start()</methodname>
in most of our examples.
</para>

<para>Il y a plusieurs options régissant la manière dont les éléments graphiques doivent être empaquetés ; cela peut sembler confus au début. Si vous avez des difficultés, nous vous suggérons l'idée de manipuler le concepteur GUI <application>glade</application> pour voir ce qui est possible. Vous pourrez même décider d'utiliser l'API <application>Gtk::Builder</application> pour charger les interfaces utilisateur au lancement du programme.</para>

<para>À la base, il y cinq styles différents comme illustré dans cette figure :</para>

<figure id="figure-box-packing1">
  <title>Empaquetage dans boîte n°1</title>
  <screenshot>
    <graphic format="PNG" fileref="figures/box_packing1.png"/>
  </screenshot>
</figure>

<para lang="en">
Each line contains one horizontal <classname>Box</classname> with
several buttons. Each of the buttons on a line is packed into the
<classname>Box</classname> with the same arguments to the
<methodname>pack_start()</methodname> method.
</para>

<para>Voici la déclaration de la fonction membre <methodname>pack_start()</methodname> :</para>
<programlisting lang="en">void pack_start(Gtk::Widget&amp; child,
                Gtk::PackOptions options = Gtk::PACK_EXPAND_WIDGET,
                guint padding = 0);</programlisting>

<para>Le premier paramètre désigne l'élément graphique à empaquer. Dans notre exemple, ce sont tous des objets <classname>Button</classname>.</para>

<para lang="en">
The <parameter>options</parameter> argument can take one of these three options:
<itemizedlist>
<listitem><para lang="en"><literal>Gtk::PACK_SHRINK</literal>: Space is contracted to the child widget size. The widget will take up just-enough space and never expand.</para></listitem>
<listitem><para lang="en"><literal>Gtk::PACK_EXPAND_PADDING</literal>: Extra space is filled with padding. The widgets will be spaced out evenly, but their sizes won't change - there will be empty space between the widgets instead. </para></listitem>
<listitem><para lang="en"><literal>Gtk::PACK_EXPAND_WIDGET</literal>: Extra space is taken up by increasing the child widget size, without changing the amount of space between widgets.</para></listitem>
</itemizedlist>
</para>

<para>Le paramètre <parameter>padding</parameter> définit la largeur de la bordure libre autour de l'élément graphique empaqueté.</para>

<para lang="en"><ulink url="http://developer.gnome.org/gtkmm/3.22/classGtk_1_1Box.html">Reference</ulink></para>

</sect4>

<sect4 id="per-container-packing-options"><title>Options d'empaquetage par conteneur</title>
<para lang="en">
Here's the constructor for the <classname>Box</classname> widget,
and methods that set per-container packing options:
<programlisting lang="en">Gtk::Box(Gtk::Orientation orientation = Gtk::ORIENTATION_HORIZONTAL, int spacing = 0);
void set_spacing(int spacing);
void set_homogeneous(bool homogeneous = true);</programlisting>
Passing <literal>true</literal> to <methodname>set_homogeneous()</methodname> will
cause all of the contained widgets to be the same size.
<parameter>spacing</parameter> is a (minimum) number of pixels to leave between
each widget.
</para>

<para>Quelle est la différence entre espacement (déterminé quand la boîte est crée) et remplissage (défini quand les éléments sont empaquetés) ? L'espacement est inséré entre les objets alors que le remplissage est ajouté sur les côtés du élément graphique. L'illustration ci-après clarifie cela :</para>

<figure id="figure-box-packing2">
  <title>Empaquetage dans boîte n°2</title>
  <screenshot>
    <graphic format="PNG" fileref="figures/box_packing2.png"/>
  </screenshot>
</figure>

</sect4>
</sect3>

<sect3 id="boxes-command-line-options">
<title lang="en">Gtk::Application and command-line options</title>
<para lang="en">The following example program requires a command-line option.
The source code shows two ways of handling command-line options in combination
with <classname>Gtk::Application</classname>.
</para>

<itemizedlist>
<listitem><para lang="en">
Handle the options in <function>main()</function> and hide them from
<classname>Gtk::Application</classname> by setting <literal>argc = 1</literal>
in the call to <methodname>Gtk::Application::create()</methodname>.
</para></listitem>

<listitem><para lang="en">
Give all command-line options to <methodname>Gtk::Application::create()</methodname>
and add the flag <literal>Gio::APPLICATION_HANDLES_COMMAND_LINE</literal>.
Connect a signal handler to the <literal>command_line</literal> signal, and
handle the command-line options in the signal handler.</para>

<para lang="en">You must set the optional parameter <literal>after = false</literal> in
the call to <literal>signal_command_line().connect()</literal>, because your signal
handler must be called before the default signal handler. You must also call
<methodname>Gio::Application::activate()</methodname> in the signal handler,
unless you want your application to exit without showing its main window.
(<classname>Gio::Application</classname> is a base class of
<classname>Gtk::Application</classname>.)
</para></listitem>
</itemizedlist>
</sect3>

<sect3 id="box-packing-example">
<title>Exemple</title>
<para>Voici le code source de l'exemple qui a servi à générer la capture d'écran ci-dessus. Quand vous lancez cet exemple, indiquez un nombre entre 1 et 3 en option de ligne de commande pour voir les diverses options d'empaquetage utilisées.</para>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/box?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>packbox.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLE_PACKBOX_H
#define GTKMM_EXAMPLE_PACKBOX_H

#include &lt;gtkmm.h&gt;

class PackBox : public Gtk::Box
{
public:
  PackBox(bool homogeneous, int spacing, Gtk::PackOptions options, int padding = 0);
  virtual ~PackBox();

protected:
  Gtk::Button m_button1, m_button2, m_button3;
  Gtk::Button* m_pbutton4;
};

#endif //GTKMM_EXAMPLE_PACKBOX_H
</programlisting>
<para lang="en">File: <filename>examplewindow.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLEWINDOW_H
#define GTKMM_EXAMPLEWINDOW_H

#include &lt;gtkmm.h&gt;

class ExampleWindow : public Gtk::Window
{
public:
  ExampleWindow(int which);
  virtual ~ExampleWindow();

protected:
  //Signal handlers:
  void on_button_quit_clicked();

  //Child widgets:
  Gtk::Button m_button;
  Gtk::Box m_box1;
  Gtk::Box m_boxQuit;
  Gtk::Button m_buttonQuit;

  Gtk::Label m_Label1, m_Label2;

  Gtk::Separator m_separator1, m_separator2;
};

#endif //GTKMM_EXAMPLEWINDOW_H
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;gtkmm/application.h&gt;
#include &lt;iostream&gt;
#include &lt;cstdlib&gt;

#define GTK_APPLICATION_RECEIVES_COMMAND_LINE_ARGUMENTS 0

#if GTK_APPLICATION_RECEIVES_COMMAND_LINE_ARGUMENTS
namespace
{
int on_command_line(const Glib::RefPtr&lt;Gio::ApplicationCommandLine&gt;&amp; command_line,
                    Glib::RefPtr&lt;Gtk::Application&gt;&amp; app)
{
  int argc = 0;
  char** argv = command_line-&gt;get_arguments(argc);

  for (int i = 0; i &lt; argc; ++i)
    std::cout &lt;&lt; "argv[" &lt;&lt; i &lt;&lt; "] = " &lt;&lt; argv[i] &lt;&lt; std::endl;

  app-&gt;activate(); // Without activate() the window won't be shown.
  return EXIT_SUCCESS;
}
} // anonymous namespace
#endif


int main(int argc, char *argv[])
{
  if (argc != 2)
  {
    std::cerr &lt;&lt; "Usage: example &lt;num&gt;, where &lt;num&gt; is 1, 2, or 3." &lt;&lt; std::endl;
    return EXIT_FAILURE;
  }

#if GTK_APPLICATION_RECEIVES_COMMAND_LINE_ARGUMENTS
  // The command line arguments must be checked before Gtk::Application::run()
  // is called. The Gio::APPLICATION_HANDLES_COMMAND_LINE flag and the
  // on_command_line() signal handler are not necessary. This program is simpler
  // without them, and with argc = 1 in the call to Gtk::Application::create().
  // They are included to show a program with Gio::APPLICATION_HANDLES_COMMAND_LINE.
  // Gio::APPLICATION_NON_UNIQUE makes it possible to run several instances of
  // this application simultaneously.
  auto app = Gtk::Application::create(argc, argv,
    "org.gtkmm.example", Gio::APPLICATION_HANDLES_COMMAND_LINE | Gio::APPLICATION_NON_UNIQUE);

  // Note after = false.
  // Only one signal handler is invoked. This signal handler must run before
  // the default signal handler, or else it won't run at all.
  app-&gt;signal_command_line().connect(sigc::bind(sigc::ptr_fun(&amp;on_command_line), app), false);
#else
  // Gio::APPLICATION_NON_UNIQUE makes it possible to run several instances of
  // this application simultaneously.
  int argc1 = 1; // Don't give the command line arguments to Gtk::Application.
  auto app = Gtk::Application::create(argc1, argv,
    "org.gtkmm.example", Gio::APPLICATION_NON_UNIQUE);
#endif

  ExampleWindow window(std::atoi(argv[1]));
  return app-&gt;run(window); //Shows the window and returns when it is closed.
}
</programlisting>
<para lang="en">File: <filename>packbox.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "packbox.h"

PackBox::PackBox(bool homogeneous, int spacing, Gtk::PackOptions options,
        int padding)
: Gtk::Box(Gtk::ORIENTATION_HORIZONTAL, spacing),
  m_button1("box.pack_start("),
  m_button2("button,"),
  m_button3((options == Gtk::PACK_SHRINK) ? "Gtk::PACK_SHRINK" :
            ((options == Gtk::PACK_EXPAND_PADDING) ?
             "Gtk::PACK_EXPAND_PADDING" : "Gtk::PACK_EXPAND_WIDGET"))
{
  set_homogeneous(homogeneous);

  pack_start(m_button1, options, padding);
  pack_start(m_button2, options, padding);
  pack_start(m_button3, options, padding);

  m_pbutton4 = new Gtk::Button(Glib::ustring::format(padding) + ");");
  pack_start(*m_pbutton4, options, padding);
}

PackBox::~PackBox()
{
  delete m_pbutton4;
}

</programlisting>
<para lang="en">File: <filename>examplewindow.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include &lt;iostream&gt;
#include "examplewindow.h"
#include "packbox.h"

ExampleWindow::ExampleWindow(int which)
: m_box1(Gtk::ORIENTATION_VERTICAL),
  m_buttonQuit("Quit")
{
  set_title("Gtk::Box example");

  PackBox *pPackBox1, *pPackBox2, *pPackBox3, *pPackBox4, *pPackBox5;

  switch(which)
  {
    case 1:
    {
      m_Label1.set_text("Gtk::Box(Gtk::ORIENTATION_HORIZONTAL); set_homogeneous(false);");

      // Align the label to the left side.
      m_Label1.set_halign(Gtk::ALIGN_START);
      m_Label1.set_valign(Gtk::ALIGN_START);

      // Pack the label into the vertical box (vbox box1).  Remember that
      // widgets added to a vbox will be packed one on top of the other in
      // order.
      m_box1.pack_start(m_Label1, Gtk::PACK_SHRINK);

      // Create a PackBox - homogeneous = false, spacing = 0,
      // options = Gtk::PACK_SHRINK, padding = 0
      pPackBox1 = Gtk::manage(new PackBox(false, 0, Gtk::PACK_SHRINK));
      m_box1.pack_start(*pPackBox1, Gtk::PACK_SHRINK);

      // Create a PackBox - homogeneous = false, spacing = 0,
      // options = Gtk::PACK_EXPAND_PADDING, padding = 0
      pPackBox2 = Gtk::manage(new PackBox(false, 0, Gtk::PACK_EXPAND_PADDING));
      m_box1.pack_start(*pPackBox2, Gtk::PACK_SHRINK);

      // Create a PackBox - homogeneous = false, spacing = 0,
      // options = Gtk::PACK_EXPAND_WIDGET, padding = 0
      pPackBox3 = Gtk::manage(new PackBox(false, 0, Gtk::PACK_EXPAND_WIDGET));
      m_box1.pack_start(*pPackBox3, Gtk::PACK_SHRINK);

      // pack the separator into the vbox.  Remember each of these
      // widgets are being packed into a vbox, so they'll be stacked
      // vertically.
      m_box1.pack_start(m_separator1, Gtk::PACK_SHRINK, 5);

      // create another new label, and show it.
      m_Label2.set_text("Gtk::Box(Gtk::ORIENTATION_HORIZONTAL); set_homogeneous(true);");
      m_Label2.set_halign(Gtk::ALIGN_START);
      m_Label2.set_valign(Gtk::ALIGN_START);
      m_box1.pack_start(m_Label2, Gtk::PACK_SHRINK);

      // Args are: homogeneous, spacing, options, padding
      pPackBox4 = Gtk::manage(new PackBox(true, 0, Gtk::PACK_EXPAND_PADDING));
      m_box1.pack_start(*pPackBox4, Gtk::PACK_SHRINK);

      // Args are: homogeneous, spacing, options, padding
      pPackBox5 = Gtk::manage(new PackBox(true, 0, Gtk::PACK_EXPAND_WIDGET));
      m_box1.pack_start(*pPackBox5, Gtk::PACK_SHRINK);

      m_box1.pack_start(m_separator2, Gtk::PACK_SHRINK, 5);

      break;
    }

    case 2:
    {

      m_Label1.set_text("Gtk::Box(Gtk::ORIENTATION_HORIZONTAL, 10); set_homogeneous(false);");
      m_Label1.set_halign(Gtk::ALIGN_START);
      m_Label1.set_valign(Gtk::ALIGN_START);
      m_box1.pack_start(m_Label1, Gtk::PACK_SHRINK);

      pPackBox1 = Gtk::manage(new PackBox(false, 10, Gtk::PACK_EXPAND_PADDING));
      m_box1.pack_start(*pPackBox1, Gtk::PACK_SHRINK);

      pPackBox2 = Gtk::manage(new PackBox(false, 10, Gtk::PACK_EXPAND_WIDGET));
      m_box1.pack_start(*pPackBox2, Gtk::PACK_SHRINK);

      m_box1.pack_start(m_separator1, Gtk::PACK_SHRINK, 5);

      m_Label2.set_text("Gtk::Box(Gtk::ORIENTATION_HORIZONTAL); set_homogeneous(false);");
      m_Label2.set_halign(Gtk::ALIGN_START);
      m_Label2.set_valign(Gtk::ALIGN_START);
      m_box1.pack_start(m_Label2, Gtk::PACK_SHRINK);

      pPackBox3 = Gtk::manage(new PackBox(false, 0, Gtk::PACK_SHRINK, 10));
      m_box1.pack_start(*pPackBox3, Gtk::PACK_SHRINK);

      pPackBox4 = Gtk::manage(new PackBox(false, 0, Gtk::PACK_EXPAND_WIDGET, 10));
      m_box1.pack_start(*pPackBox4, Gtk::PACK_SHRINK);

      m_box1.pack_start(m_separator2, Gtk::PACK_SHRINK, 5);

      break;
    }

    case 3:
    {
      // This demonstrates the ability to use Gtk::Box::pack_end() to
      // right justify widgets.  First, we create a new box as before.
      pPackBox1 = Gtk::manage(new PackBox(false, 0, Gtk::PACK_SHRINK));

      // create the label that will be put at the end.
      m_Label1.set_text("end");

      // pack it using pack_end(), so it is put on the right side
      // of the PackBox.
      pPackBox1-&gt;pack_end(m_Label1, Gtk::PACK_SHRINK);

      m_box1.pack_start(*pPackBox1, Gtk::PACK_SHRINK);

      // this explicitly sets the separator to 500 pixels wide by 5 pixels
      // high.  This is so the hbox we created will also be 500 pixels wide,
      // and the "end" label will be separated from the other labels in the
      // hbox.  Otherwise, all the widgets in the hbox would be packed as
      // close together as possible.
      m_separator1.set_size_request(500, 5);

      // pack the separator into the vbox.
      m_box1.pack_start(m_separator1, Gtk::PACK_SHRINK, 5);

      break;
    }

    default:
    {
      std::cerr &lt;&lt; "Unexpected command-line option." &lt;&lt; std::endl;
      break;
    }
  }

  // Connect the signal to hide the window:
  m_buttonQuit.signal_clicked().connect( sigc::mem_fun(*this,
              &amp;ExampleWindow::on_button_quit_clicked) );

  // pack the button into the quitbox.
  // The last 2 arguments to Box::pack_start are: options, padding.
  m_boxQuit.pack_start(m_buttonQuit, Gtk::PACK_EXPAND_PADDING);
  m_box1.pack_start(m_boxQuit, Gtk::PACK_SHRINK);

  // pack the vbox (box1) which now contains all our widgets, into the
  // main window.
  add(m_box1);

  show_all_children();
}

ExampleWindow::~ExampleWindow()
{
}

void ExampleWindow::on_button_quit_clicked()
{
  hide();
}

</programlisting>
<!-- end inserted example code -->
</sect3>

</sect2>

<sect2 id="sec-buttonbox">
<title>Boîtes à boutons</title>

<para lang="en">
Button boxes are a convenient way to quickly arrange a group of buttons. Their
orientation can be either horizontal or vertical.
</para>

<para>Les <classname>ButtonBox</classname> donnent une apparence homogène aux applications en utilisant des réglages normalisés pour l'espacement entre boutons et pour l'empaquetage.</para>

<para>Les boutons sont insérés dans l'objet <classname>ButtonBox</classname> à l'aide de la fonction membre <methodname>add()</methodname>.</para>

<para>Les boîtes à boutons prennent en charge divers styles de dispositions. Le style peut être obtenu et modifié avec les fonctions membres <methodname>get_layout()</methodname> et <methodname>set_layout()</methodname>.</para>

<para lang="en"><ulink url="http://developer.gnome.org/gtkmm/3.22/classGtk_1_1ButtonBox.html">Reference</ulink></para>

<sect3 id="buttonbox-example">
<title>Exemple</title>

<figure id="figure-buttonbox">
  <title>Boîte à bouton</title>
  <screenshot>
    <graphic format="PNG" fileref="figures/buttonbox.png"/>
  </screenshot>
</figure>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/buttonbox?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>examplewindow.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLEWINDOW_H
#define GTKMM_EXAMPLEWINDOW_H

#include &lt;gtkmm.h&gt;

class ExampleWindow : public Gtk::Window
{
public:
  ExampleWindow();
  virtual ~ExampleWindow();

protected:
  //Signal handlers:
  void on_button_clicked();

  //Child widgets:
  Gtk::Box m_VBox_Main, m_VBox;
  Gtk::Box m_HBox;
  Gtk::Frame m_Frame_Horizontal, m_Frame_Vertical;
};

#endif //GTKMM_EXAMPLEWINDOW_H
</programlisting>
<para lang="en">File: <filename>examplebuttonbox.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLE_BUTTONBOX_H
#define GTKMM_EXAMPLE_BUTTONBOX_H

#include &lt;gtkmm.h&gt;

class ExampleButtonBox : public Gtk::Frame
{
public:
  ExampleButtonBox(bool horizontal,
       const Glib::ustring&amp; title,
       gint spacing,
       Gtk::ButtonBoxStyle layout);

protected:
  Gtk::Button m_Button_OK, m_Button_Cancel, m_Button_Help;
};

#endif //GTKMM_EXAMPLE_BUTTONBOX_H
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;gtkmm/application.h&gt;

int main(int argc, char *argv[])
{
  auto app = Gtk::Application::create(argc, argv, "org.gtkmm.example");

  ExampleWindow window;

  //Shows the window and returns when it is closed.
  return app-&gt;run(window);
}
</programlisting>
<para lang="en">File: <filename>examplebuttonbox.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplebuttonbox.h"

ExampleButtonBox::ExampleButtonBox(bool horizontal,
       const Glib::ustring&amp; title,
       gint spacing,
       Gtk::ButtonBoxStyle layout)
: Gtk::Frame(title),
  m_Button_OK("OK"),
  m_Button_Cancel("Cancel"),
  m_Button_Help("Help")
{
  Gtk::ButtonBox* bbox = nullptr;

  if(horizontal)
    bbox = Gtk::manage( new Gtk::ButtonBox(Gtk::ORIENTATION_HORIZONTAL) );
  else
    bbox = Gtk::manage( new Gtk::ButtonBox(Gtk::ORIENTATION_VERTICAL) );

  bbox-&gt;set_border_width(5);

  add(*bbox);

  /* Set the appearance of the Button Box */
  bbox-&gt;set_layout(layout);
  bbox-&gt;set_spacing(spacing);

  bbox-&gt;add(m_Button_OK);
  bbox-&gt;add(m_Button_Cancel);
  bbox-&gt;add(m_Button_Help);
}

</programlisting>
<para lang="en">File: <filename>examplewindow.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include "examplebuttonbox.h"

ExampleWindow::ExampleWindow()
: m_VBox_Main(Gtk::ORIENTATION_VERTICAL),
  m_VBox(Gtk::ORIENTATION_VERTICAL),
  m_Frame_Horizontal("Horizontal Button Boxes"),
  m_Frame_Vertical("Vertical Button Boxes")
{
  set_title("Gtk::ButtonBox");
  add(m_VBox_Main);

  m_VBox_Main.pack_start(m_Frame_Horizontal, Gtk::PACK_EXPAND_WIDGET, 10);

  //The horizontal ButtonBoxes:
  m_VBox.set_border_width(10);
  m_Frame_Horizontal.add(m_VBox);

  m_VBox.pack_start(*Gtk::manage(
              new ExampleButtonBox(true, "Spread (spacing 40)", 40,
                  Gtk::BUTTONBOX_SPREAD)),
          Gtk::PACK_EXPAND_WIDGET);

  m_VBox.pack_start(*Gtk::manage(
              new ExampleButtonBox(true, "Edge (spacing 30)", 30,
                  Gtk::BUTTONBOX_EDGE)),
          Gtk::PACK_EXPAND_WIDGET, 5);

  m_VBox.pack_start(*Gtk::manage(
              new ExampleButtonBox(true, "Start (spacing 20)", 20,
                  Gtk::BUTTONBOX_START)),
          Gtk::PACK_EXPAND_WIDGET, 5);

  m_VBox.pack_start(*Gtk::manage(
              new ExampleButtonBox(true, "end (spacing 10)", 10,
                  Gtk::BUTTONBOX_END)),
          Gtk::PACK_EXPAND_WIDGET, 5);


  //The vertical ButtonBoxes:
  m_VBox_Main.pack_start(m_Frame_Vertical, Gtk::PACK_EXPAND_WIDGET, 10);

  m_HBox.set_border_width(10);
  m_Frame_Vertical.add(m_HBox);

  m_HBox.pack_start(*Gtk::manage(
              new ExampleButtonBox(false, "Spread (spacing 5)", 5,
                  Gtk::BUTTONBOX_SPREAD)),
          Gtk::PACK_EXPAND_WIDGET);

  m_HBox.pack_start(*Gtk::manage(
              new ExampleButtonBox(false, "Edge (spacing 30)", 30,
                  Gtk::BUTTONBOX_EDGE)),
          Gtk::PACK_EXPAND_WIDGET, 5);

  m_HBox.pack_start(*Gtk::manage(
              new ExampleButtonBox(false, "Start (spacing 20)", 20,
                  Gtk::BUTTONBOX_START)),
          Gtk::PACK_EXPAND_WIDGET, 5);

  m_HBox.pack_start(*Gtk::manage(new ExampleButtonBox(false, "End (spacing 10)",
                  10, Gtk::BUTTONBOX_END)),
          Gtk::PACK_EXPAND_WIDGET, 5);

  show_all_children();
}

ExampleWindow::~ExampleWindow()
{
}

void ExampleWindow::on_button_clicked()
{
  hide();
}
</programlisting>
<!-- end inserted example code -->

</sect3>

</sect2>

<sect2 id="sec-grid">
<title>Grille</title>

<para lang="en">
A <classname>Grid</classname> dynamically lays out child widgets in rows and
columns. The dimensions of the grid do not need to be specified in the constructor.
</para>

<para lang="en">
Child widgets can span multiple rows or columns, using
<methodname>attach()</methodname>, or added next to an existing widget inside
the grid with <methodname>attach_next_to()</methodname>. Individual rows and columns of the grid can be set to have uniform height or width with
<methodname>set_row_homogeneous()</methodname> and
<methodname>set_column_homogeneous()</methodname>.
</para>
<para lang="en">You can set the <emphasis>margin</emphasis> and <emphasis>expand</emphasis> properties of the
child <classname>Widget</classname>s to control their spacing and their behaviour when the Grid is resized.
</para>

<para lang="en"><ulink url="http://developer.gnome.org/gtkmm/3.22/classGtk_1_1Grid.html">Reference</ulink></para>

<sect3 id="grid-example"><title>Exemple</title>
<para lang="en">
This example creates a window with three buttons in a grid.
The first two buttons are in the upper row, from left to right. A
third button is attached underneath the first button, in a new lower row,
spanning two columns.
</para>

<figure id="figure-grid">
  <title>Grille</title>
  <screenshot>
    <graphic format="PNG" fileref="figures/grid.png"/>
  </screenshot>
</figure>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/grid?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>examplewindow.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLEWINDOW_H
#define GTKMM_EXAMPLEWINDOW_H

#include &lt;gtkmm.h&gt;

class ExampleWindow : public Gtk::Window
{
public:
  ExampleWindow();
  virtual ~ExampleWindow();

private:
  // Signal handlers:
  void on_button_quit();
  void on_button_numbered(const Glib::ustring&amp; data);

  // Child widgets:
  Gtk::Grid m_grid;
  Gtk::Button m_button_1, m_button_2, m_button_quit;
};

#endif /* GTKMM_EXAMPLEWINDOW_H */
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;gtkmm/application.h&gt;

int main(int argc, char *argv[])
{
  auto app = Gtk::Application::create(argc, argv, "org.gtkmm.example");

  ExampleWindow window;

  // Shows the window and returns when it is closed.
  return app-&gt;run(window);
}
</programlisting>
<para lang="en">File: <filename>examplewindow.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include &lt;iostream&gt;
#include "examplewindow.h"

ExampleWindow::ExampleWindow()
: m_button_1("button 1"),
  m_button_2("button 2"),
  m_button_quit("Quit")
{
  set_title("Gtk::Grid");
  set_border_width(12);

  add(m_grid);

  m_grid.add(m_button_1);
  m_grid.add(m_button_2);
  m_grid.attach_next_to(m_button_quit, m_button_1, Gtk::POS_BOTTOM, 2, 1);

  m_button_1.signal_clicked().connect(
    sigc::bind&lt;Glib::ustring&gt;( sigc::mem_fun(*this,
      &amp;ExampleWindow::on_button_numbered), "button 1") );
  m_button_2.signal_clicked().connect(
    sigc::bind&lt;Glib::ustring&gt;( sigc::mem_fun(*this,
      &amp;ExampleWindow::on_button_numbered), "button 2") );

  m_button_quit.signal_clicked().connect(sigc::mem_fun(*this,
    &amp;ExampleWindow::on_button_quit) );

  show_all_children();
}

ExampleWindow::~ExampleWindow()
{
}

void ExampleWindow::on_button_quit()
{
  hide();
}

void
ExampleWindow::on_button_numbered(const Glib::ustring&amp; data)
{
  std::cout &lt;&lt; data &lt;&lt; " was pressed" &lt;&lt; std::endl;
}
</programlisting>
<!-- end inserted example code -->

</sect3>

</sect2>

<sect2 id="sec-table">
<title>Tableau</title>

<para lang="en">
<classname>Gtk::Table</classname> allows us to place widgets in a grid,
similar to <classname>Gtk::Grid</classname>.
</para>
<para lang="en">
<classname>Gtk::Table</classname> is deprecated from <application>gtkmm</application> version 3.4 and should
not be used in newly-written code. Use <classname>Gtk::Grid</classname> instead.
</para>
</sect2>

<sect2 id="sec-notebook">
<title>Bloc-note</title>

<para>L'objet <classname>Notebook</classname> est constitué d'un jeu de <literal>pages</literal> empilées, chacune contenant des éléments graphiques. Les onglets étiquetés permettent à l'utilisateur de choisir les pages. <classname>Notebook</classname> permet de placer plusieurs jeux d'éléments graphiques dans un espace réduit, mais en ne montrant qu'une seule page à la fois. Cet objet est souvent utilisé, par exemple, dans les boîtes de dialogue de préférences.</para>

<para>Servez-vous des fonctions membres <methodname>append_page()</methodname>, <methodname>prepend_page()</methodname> et <methodname>insert_page()</methodname> pour ajouter des pages à onglets dans l'objet <literal>Notebook</literal> en précisant l'élément graphique enfant et le nom de l'onglet.</para>

<para>Pour connaître la page actuellement affichée, utilisez la fonction membre <methodname>get_current_page()</methodname>. Elle renvoie un numéro de page, puis, en appelant <methodname>get_nth_page()</methodname> avec ce numéro de page, vous obtiendrez un pointeur sur l'élément graphique enfant de la page.</para>

<para>Pour changer de page sélectionnée au cours du programme, utilisez la fonction membre <methodname>set_current_page()</methodname>.</para>

<para lang="en"><ulink url="http://developer.gnome.org/gtkmm/3.22/classGtk_1_1Notebook.html">Reference</ulink></para>

<sect3 id="notebook-example"><title>Exemple</title>

<figure id="figure-notebook">
  <title>Bloc-note</title>
  <screenshot>
    <graphic format="PNG" fileref="figures/notebook.png"/>
  </screenshot>
</figure>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/notebook/?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>examplewindow.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLEWINDOW_H
#define GTKMM_EXAMPLEWINDOW_H

#include &lt;gtkmm.h&gt;

class ExampleWindow : public Gtk::Window
{
public:
  ExampleWindow();
  virtual ~ExampleWindow();

protected:
  //Signal handlers:
  void on_button_quit();
  void on_notebook_switch_page(Gtk::Widget* page, guint page_num);

  //Child widgets:
  Gtk::Box m_VBox;
  Gtk::Notebook m_Notebook;
  Gtk::Label m_Label1, m_Label2;

  Gtk::ButtonBox m_ButtonBox;
  Gtk::Button m_Button_Quit;
};

#endif //GTKMM_EXAMPLEWINDOW_H
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;gtkmm/application.h&gt;

int main(int argc, char *argv[])
{
  auto app = Gtk::Application::create(argc, argv, "org.gtkmm.example");

  ExampleWindow window;

  //Shows the window and returns when it is closed.
  return app-&gt;run(window);
}
</programlisting>
<para lang="en">File: <filename>examplewindow.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include &lt;iostream&gt;
#include "examplewindow.h"

ExampleWindow::ExampleWindow()
: m_VBox(Gtk::ORIENTATION_VERTICAL),
  m_Label1("Contents of tab 1"),
  m_Label2("Contents of tab 2"),
  m_Button_Quit("Quit")
{
  set_title("Gtk::Notebook example");
  set_border_width(10);
  set_default_size(400, 200);


  add(m_VBox);

  //Add the Notebook, with the button underneath:
  m_Notebook.set_border_width(10);
  m_VBox.pack_start(m_Notebook);
  m_VBox.pack_start(m_ButtonBox, Gtk::PACK_SHRINK);

  m_ButtonBox.pack_start(m_Button_Quit, Gtk::PACK_SHRINK);
  m_Button_Quit.signal_clicked().connect(sigc::mem_fun(*this,
              &amp;ExampleWindow::on_button_quit) );

  //Add the Notebook pages:
  m_Notebook.append_page(m_Label1, "First");
  m_Notebook.append_page(m_Label2, "Second");

  m_Notebook.signal_switch_page().connect(sigc::mem_fun(*this,
              &amp;ExampleWindow::on_notebook_switch_page) );

  show_all_children();
}

ExampleWindow::~ExampleWindow()
{
}

void ExampleWindow::on_button_quit()
{
  hide();
}

void ExampleWindow::on_notebook_switch_page(Gtk::Widget* /* page */, guint page_num)
{
  std::cout &lt;&lt; "Switched to tab with index " &lt;&lt; page_num &lt;&lt; std::endl;

  //You can also use m_Notebook.get_current_page() to get this index.
}
</programlisting>
<!-- end inserted example code -->

</sect3>

</sect2>

<sect2 id="sec-assistant">
<title>Assistant</title>

<para>Un objet <classname>Assistant</classname> divise une opération complexe en étapes successives. À chaque étape correspond une page, avec un en-tête, un élément graphique enfant et une zone d'action. La zone d'action de l'assistant possède des boutons de navigation qui se mettent à jour automatiquement selon le type de page fixé avec <methodname>set_page_type()</methodname>.</para>

<para>Utilisez les fonctions membres <methodname>append_page()</methodname>, <methodname>prepend_page</methodname> et <methodname>insert_page()</methodname> pour ajouter des pages à un objet <classname>Assistant</classname>, tout en indiquant l'élément graphique enfant pour chacune d'entre elles.</para>

<para>Pour connaître la page en cours d'utilisation, servez-vous de la fonction membre <methodname>get_current_page()</methodname>, passez le résultat à <methodname>get_nth_page()</methodname> qui vous renverra un pointeur sur l'élément graphique affiché. Pour changer en cours de programme la page active, utilisez la fonction membre <methodname>set_current_page()</methodname>.</para>

<para>Pour définir le titre de la page, servez-vous de la fonction membre <methodname>set_page_title()</methodname>. Les images de l'en-tête et du côté de la page sont insérées avec les fonctions membres <methodname>set_page_header_image()</methodname> et <methodname>set_page_side_image()</methodname>.</para>

<para>Pour ajouter des éléments graphiques dans la zone d'action, utilisez la fonction membre <methodname>add_action_widget()</methodname>. Ils seront empaquetés à côté des boutons par défaut. Servez-vous de la fonction membre <methodname>remove_action_widget()</methodname> pour enlever des éléments graphiques.</para>

<para lang="en"><ulink url="http://developer.gnome.org/gtkmm/3.22/classGtk_1_1Assistant.html">Reference</ulink></para>

<sect3 id="assistant-example"><title>Exemple</title>

<figure id="figure-assistant">
  <title>Assistant</title>
  <screenshot>
    <graphic format="PNG" fileref="figures/assistant.png"/>
  </screenshot>
</figure>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/assistant/?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>exampleassistant.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLEASSISTANT_H
#define GTKMM_EXAMPLEASSISTANT_H

#include &lt;gtkmm.h&gt;

class ExampleAssistant : public Gtk::Assistant
{
public:
  ExampleAssistant();
  virtual ~ExampleAssistant();

  void get_result(bool&amp; check_state, Glib::ustring&amp; entry_text);

private:
  // Signal handlers:
  void on_assistant_apply();
  void on_assistant_cancel();
  void on_assistant_close();
  void on_assistant_prepare(Gtk::Widget* widget);
  void on_entry_changed();

  // Member functions:
  void print_status();

  // Child widgets:
  Gtk::Box m_box;
  Gtk::Label m_label1, m_label2;
  Gtk::CheckButton m_check;
  Gtk::Entry m_entry;
};

#endif /* GTKMM_EXAMPLEASSISTANT_H */
</programlisting>
<para lang="en">File: <filename>examplewindow.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLEWINDOW_H
#define GTKMM_EXAMPLEWINDOW_H

#include "exampleassistant.h"
#include &lt;gtkmm.h&gt;

class ExampleWindow : public Gtk::Window
{
public:
  ExampleWindow();
  virtual ~ExampleWindow();

private:
  // Signal handlers:
  void on_button_clicked();
  void on_assistant_apply();

  // Child widgets:
  Gtk::Grid m_grid;
  Gtk::Button m_button;
  Gtk::Label m_label1, m_label2;
  Gtk::CheckButton m_check;
  Gtk::Entry m_entry;
  ExampleAssistant m_assistant;
};

#endif /* GTKMM_EXAMPLEWINDOW_H */
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;gtkmm/application.h&gt;

int main(int argc, char *argv[])
{
  auto app = Gtk::Application::create(argc, argv, "org.gtkmm.example");

  ExampleWindow window;

  // Shows the window and returns when it is closed.
  return app-&gt;run(window);
}
</programlisting>
<para lang="en">File: <filename>examplewindow.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include "exampleassistant.h"

ExampleWindow::ExampleWindow()
: m_button("Show the assistant"),
  m_label1("State of assistant checkbutton:", Gtk::ALIGN_START, Gtk::ALIGN_CENTER),
  m_label2("Contents of assistant entry:", Gtk::ALIGN_START, Gtk::ALIGN_CENTER)
{
  set_title("Gtk::Assistant example");
  set_border_width(12);

  m_grid.set_row_homogeneous(true);

  m_grid.attach(m_button, 0, 0, 2, 1);
  m_button.set_hexpand(true);
  m_button.set_valign(Gtk::ALIGN_CENTER);

  m_grid.attach(m_label1, 0, 1, 1, 1);

  m_grid.attach(m_label2, 0, 2, 1, 1);

  m_grid.attach(m_check, 1, 1, 1, 1);
  m_check.set_halign(Gtk::ALIGN_START);

  m_grid.attach(m_entry, 1, 2, 1, 1);
  m_entry.set_hexpand(true);

  add(m_grid);

  m_button.signal_clicked().connect(sigc::mem_fun(*this,
    &amp;ExampleWindow::on_button_clicked));
  m_assistant.signal_apply().connect(sigc::mem_fun(*this,
    &amp;ExampleWindow::on_assistant_apply));

  m_check.set_sensitive(false);
  m_entry.set_sensitive(false);

  show_all_children();
}

ExampleWindow::~ExampleWindow()
{
}

void ExampleWindow::on_assistant_apply()
{
  bool check_state;
  Glib::ustring entry_text;

  m_assistant.get_result(check_state, entry_text);
  m_check.set_active(check_state);
  m_entry.set_text(entry_text);
}

void ExampleWindow::on_button_clicked()
{
  m_assistant.show();
}
</programlisting>
<para lang="en">File: <filename>exampleassistant.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include &lt;iostream&gt;
#include "exampleassistant.h"

ExampleAssistant::ExampleAssistant()
: m_box(Gtk::ORIENTATION_HORIZONTAL, 12),
  m_label1("Type text to allow the assistant to continue:"),
  m_label2("Confirmation page"),
  m_check("Optional extra information")
{
  set_title("Gtk::Assistant example");
  set_border_width(12);
  set_default_size(400, 300);

  m_box.pack_start(m_label1);
  m_box.pack_start(m_entry);

  append_page(m_box);
  append_page(m_check);
  append_page(m_label2);

  set_page_title(*get_nth_page(0), "Page 1");
  set_page_title(*get_nth_page(1), "Page 2");
  set_page_title(*get_nth_page(2), "Confirmation");

  set_page_complete(m_check, true);
  set_page_complete(m_label2, true);

  set_page_type(m_box, Gtk::ASSISTANT_PAGE_INTRO);
  set_page_type(m_label2, Gtk::ASSISTANT_PAGE_CONFIRM);

  signal_apply().connect(sigc::mem_fun(*this,
    &amp;ExampleAssistant::on_assistant_apply));
  signal_cancel().connect(sigc::mem_fun(*this,
    &amp;ExampleAssistant::on_assistant_cancel));
  signal_close().connect(sigc::mem_fun(*this,
    &amp;ExampleAssistant::on_assistant_close));
  signal_prepare().connect(sigc::mem_fun(*this,
    &amp;ExampleAssistant::on_assistant_prepare));

  m_entry.signal_changed().connect(sigc::mem_fun(*this,
    &amp;ExampleAssistant::on_entry_changed));

  show_all_children();
}

ExampleAssistant::~ExampleAssistant()
{
}

void ExampleAssistant::get_result(bool&amp; check_state, Glib::ustring&amp; entry_text)
{
  check_state = m_check.get_active();
  entry_text = m_entry.get_text();
}

void ExampleAssistant::on_assistant_apply()
{
  std::cout &lt;&lt; "Apply was clicked";
  print_status();
}

void ExampleAssistant::on_assistant_cancel()
{
  std::cout &lt;&lt; "Cancel was clicked";
  print_status();
  hide();
}

void ExampleAssistant::on_assistant_close()
{
  std::cout &lt;&lt; "Assistant was closed";
  print_status();
  hide();
}

void ExampleAssistant::on_assistant_prepare(Gtk::Widget* /* widget */)
{
  set_title(Glib::ustring::compose("Gtk::Assistant example (Page %1 of %2)",
    get_current_page() + 1, get_n_pages()));
}

void ExampleAssistant::on_entry_changed()
{
  // The page is only complete if the entry contains text.
  if(m_entry.get_text_length())
    set_page_complete(m_box, true);
  else
    set_page_complete(m_box, false);
}

void ExampleAssistant::print_status()
{
  std::cout &lt;&lt; ", entry contents: \"" &lt;&lt; m_entry.get_text()
    &lt;&lt; "\", checkbutton status: " &lt;&lt; m_check.get_active() &lt;&lt; std::endl;
}
</programlisting>
<!-- end inserted example code -->

</sect3>

</sect2>

</sect1>

</chapter>

<chapter id="chapter-treeview">

<title>L'élément graphique arborescence</title>
<para>L'élément graphique <classname>Gtk::TreeView</classname> peut incorporer des listes ou des arborescences de données, disposées en colonnes.</para>

<sect1 id="sec-treeview-model">
<title>Le modèle</title>
<para>Chaque objet <classname>Gtk::TreeView</classname> possède un objet <classname>Gtk::TreeModel</classname> associé ; il contient les données à afficher par l'objet <classname>TreeView</classname>. Tout <classname>Gtk::TreeModel</classname> peut être utilisé par plus d'un <classname>Gtk::TreeView</classname>. Par exemple, il est possible d'afficher et modifier simultanément sous deux formes différentes les mêmes données sous-jacentes ; ou bien encore, les deux vues peuvent afficher des colonnes différentes à partir du même modèle de données, tout comme deux requêtes SQL (ou « vues ») sont susceptibles d'afficher des champs différents à partir d'une même base de données.</para>
<para>Même si vous pouvez théoriquement implémenter votre propre modèle, vous utiliserez normalement, soit la classe modèle <classname>ListStore</classname>, soit la classe modèle <classname>TreeStore</classname>.</para>

<para lang="en"><ulink url="http://developer.gnome.org/gtkmm/3.22/classGtk_1_1TreeModel.html">Reference</ulink></para>

<sect2 id="treeview-model-liststore">
<title>Modèle listStore, pour des colonnes</title>
<para>Un objet <classname>ListStore</classname> contient de simples colonnes de données et chaque colonne n'a pas d'enfant.</para>

<figure id="figure-treeview-liststore-model">
  <title>TreeView - ListStore</title>
  <screenshot>
    <graphic format="PNG" fileref="figures/treeview_list.png"/>
  </screenshot>
</figure>

<para lang="en"><ulink url="http://developer.gnome.org/gtkmm/3.22/classGtk_1_1ListStore.html">Reference</ulink></para>

</sect2>

<sect2 id="treeview-model-treestore">
<title>Modèle treeStore, pour une hiérarchie</title>
<para>L'objet <classname>TreeStore</classname> contient des colonnes de données et chaque colonne peut avoir des colonnes enfants.</para>

<figure id="figure-treeview-treestore-model">
  <title>TreeView - TreeStore</title>
  <screenshot>
    <graphic format="PNG" fileref="figures/treeview_tree.png"/>
  </screenshot>
</figure>

<para lang="en"><ulink url="http://developer.gnome.org/gtkmm/3.22/classGtk_1_1TreeStore.html">Reference</ulink></para>

</sect2>

<sect2 id="treeview-model-columns">
<title>Modèle colonnes</title>
<para>La classe <classname>TreeModelColumnRecord</classname> s'utilise pour enregistrer les colonnes et leurs types de données. Vous ajoutez des exemplaires de <classname>TreeModelColumn</classname> au <classname>ColumnRecord</classname>, puis utilisez ces <classname>TreeModelColumns</classname> pour obtenir ou placer les données dans les colonnes du modèle. Vous trouverez certainement commode de dériver un nouveau <classname>TreeModelColumnRecord</classname> incorporant vos exemplaires de <classname>TreeModelColumn</classname> en tant que données membres.</para>

<programlisting>class ModelColumns : public Gtk::TreeModelColumnRecord
{
public:

  ModelColumns()
    { add(m_col_text); add(m_col_number); }

  Gtk::TreeModelColumn&lt;Glib::ustring&gt; m_col_text;
  Gtk::TreeModelColumn&lt;int&gt; m_col_number;
};

ModelColumns m_Columns;</programlisting>

<para>Vous précisez le <classname>ColumnRecord</classname> à la création du modèle, ainsi :</para>
<programlisting>Glib::RefPtr&lt;Gtk::ListStore&gt; refListStore =
    Gtk::ListStore::create(m_Columns);</programlisting>
<para>Notez que les exemplaires de colonnes (tels que m_Columns ici) ne sont habituellement pas qualifiés « static », étant donné qu'ils doivent être instanciés après que glibmm l'ait été lui-même.</para>
</sect2>

<sect2 id="treeview-adding-rows">
<title>Ajout de lignes</title>
<para>Ajoutez des lignes au modèle avec les fonctions membres <methodname>append()</methodname>, <methodname>prepend()</methodname> ou <methodname>insert()</methodname>.</para>
<programlisting>Gtk::TreeModel::iterator iter = m_refListStore-&gt;append();</programlisting>
<para>Vous pouvez déréférencer l'itérateur pour obtenir la ligne :</para>
<programlisting>Gtk::TreeModel::Row row = *iter;</programlisting>
<sect3 id="treeview-adding-child-rows"><title>Ajout de colonnes enfants</title>
<para>Les modèles <classname>Gtk::TreeStore</classname> peuvent avoir des éléments enfants. Pour les ajouter, servez-vous des fonctions membres <methodname>append()</methodname>, <methodname>prepend()</methodname> ou <methodname>insert()</methodname>, ainsi : </para>
<programlisting lang="en">Gtk::TreeModel::iterator iter_child =
    m_refTreeStore-&gt;append(row.children());</programlisting>
</sect3>

</sect2>

<sect2 id="treeview-setting-values">
<title>Définition des valeurs</title>
<para>Vous pouvez utiliser la surdéfinition de <methodname>operator[]</methodname> pour définir les données d'une colonne désignée dans la ligne en indiquant le <classname>TreeModelColumn</classname> utilisé pour créer le modèle.</para>
<programlisting>row[m_Columns.m_col_text] = "textedonné";</programlisting>
</sect2>

<sect2 id="treeview-getting-values">
<title>Obtention des valeurs</title>
<para>Vous pouvez utiliser la surdéfinition de <methodname>operator[]</methodname> pour obtenir les données d'une colonne particulière dans une ligne, en précisant le <classname>TreeModelColumn</classname> qui a été utilisé pour créer le modèle.</para>
<programlisting>Glib::ustring strText = row[m_Columns.m_col_text];
int number = row[m_Columns.m_col_number];</programlisting>
<para>Le compilateur se plaint si vous utilisez un type inapproprié et génère, par exemple, l'erreur de compilation suivante :</para>
<programlisting>//compiler error - no conversion from ustring to int.
int number = row[m_Columns.m_col_text];</programlisting>
</sect2>

<sect2 id="treeview-hidden-columns">
<title>Colonnes « cachées »</title>
<para>Vous pouvez associer des données supplémentaires à chaque ligne. Pour ce faire, ajoutez-les en tant que colonne du modèle, mais sans les placer dans la vue.</para>
</sect2>

</sect1>

<sect1 id="sec-treeview">
<title>La vue</title>
<para>La vue est l'élément graphique (<classname>Gtk::TreeView</classname>) qui affiche concrètement les données du modèle (<classname>Gtk::TreeModel</classname>) et qui autorise l'utilisateur à interagir. Elle peut afficher, de diverses manières, toutes les colonnes du modèle ou seulement quelques unes.</para>

<para lang="en"><ulink url="http://developer.gnome.org/gtkmm/3.22/classGtk_1_1TreeView.html">Reference</ulink></para>

<sect2 id="sec-treeview-using-a-model">
<title>Utilisation d'un modèle</title>
<para>Vous pouvez définir le modèle <classname>Gtk::TreeModel</classname> à la construction de l'objet vue <classname>Gtk::TreeView</classname> ou bien vous pouvez utiliser la fonction membre <methodname>set_model()</methodname>, comme suit :</para>
<programlisting>m_TreeView.set_model(m_refListStore);</programlisting>
</sect2>

<sect2 id="treeview-adding-view-columns">
<title>Ajout de colonnes à la vue</title>
<para>Vous pouvez utiliser la fonction membre <methodname>append_column()</methodname> pour demander à la vue d'afficher certaines colonnes du modèle, dans un certain ordre, avec un certain intitulé.</para>
<programlisting>m_TreeView.append_column("Messages", m_Columns.m_col_text);</programlisting>
<para>En utilisant cette simple surdéfinition de <methodname>append_column()</methodname>, l'objet <classname>TreeView</classname> affiche la donnée du modèle avec un <classname>CellRenderer</classname> approprié. Par exemple, les chaînes littérales et les nombres sont affichés dans un simple contrôle <classname>Gtk::Entry</classname> et les booléens dans un <classname>Gtk::CheckButton</classname>. Cela correspond aux besoins habituels. Pour des colonnes relatives à d'autres types, vous pouvez, soit connecter une fonction de rappel qui convertit avec <methodname>TreeViewColumn::set_cell_data_func()</methodname> le type en chaîne littérale le représentant, soit créer par dérivation un <classname>CellRenderer</classname> personnalisé. Notez que le type <literal>(unsigned) short</literal> n'est pas pris en charge par défaut — à la place, vous pouvez utiliser le type <literal>(unsigned) int</literal> ou <literal>(unsigned) long</literal>.</para>
</sect2>

<sect2 id="treeview-multiple-model-columns-per-view-column">
<title>Plus d'une colonne de modèle par colonne de vue</title>
<para>Pour afficher à l'écran plus d'une colonne du modèle dans une colonne de vue, vous aurez besoin de créer un élément graphique <classname>TreeView::Column</classname> manuellement et d'utiliser la fonction membre <methodname>pack_start()</methodname> pour y ajouter les colonnes du modèle.</para>

<para lang="en">
Then use <methodname>append_column()</methodname> to add the view Column to the
View. Notice that <methodname>Gtk::TreeView::append_column()</methodname> is overridden
to accept either a prebuilt <classname>Gtk::TreeView::Column</classname> widget, or
just the <classname>TreeModelColumn</classname> from which it generates an
appropriate <classname>Gtk::TreeView::Column</classname> widget.
</para>
<para lang="en">
Here is some example code from
<filename>gtkmm/demos/gtk-demo/example_icontheme.cc</filename>, which has a pixbuf
icon and a text name in the same column:
</para>
<programlisting lang="en">Gtk::TreeView::Column* pColumn =
  Gtk::manage(new Gtk::TreeView::Column("Icon Name"));

// m_columns.icon and m_columns.iconname are columns in the model.
// pColumn is the column in the TreeView:
pColumn-&gt;pack_start(m_columns.icon, /* expand= */ false);
pColumn-&gt;pack_start(m_columns.iconname);

m_TreeView.append_column(*pColumn);</programlisting>
</sect2>

<sect2 id="treeview-cellrenderer-details">
<title>Détails pour la définition du CellRenderer</title>
<para lang="en">
The default <classname>CellRenderers</classname> and their default behaviour
will normally suffice, but you might occasionally need finer control. For
instance, this example code from
<filename>gtkmm/demos/gtk-demo/example_treeview_treestore.cc</filename>, appends a
<classname>Gtk::CellRenderer</classname> widget and instructs it to render the
data from various model columns through various aspects of its appearance.
</para>
<programlisting lang="en">int cols_count = m_TreeView.append_column_editable("Alex", m_columns.alex);
Gtk::TreeViewColumn* pColumn = m_TreeView.get_column(cols_count-1);
if(pColumn)
{
  Gtk::CellRendererToggle* pRenderer =
    static_cast&lt;Gtk::CellRendererToggle*&gt;(pColumn-&gt;get_first_cell());
  pColumn-&gt;add_attribute(pRenderer-&gt;property_visible(), m_columns.visible);
  pColumn-&gt;add_attribute(pRenderer-&gt;property_activatable(), m_columns.world);</programlisting>

<para>Vous pouvez aussi connecter les signaux du <classname>CellRenderer</classname> pour détecter des actions utilisateur. Par exemple :</para>
<programlisting>Gtk::CellRendererToggle* pRenderer =
    Gtk::manage( new Gtk::CellRendererToggle() );
pRenderer-&gt;signal_toggled().connect(
    sigc::bind( sigc::mem_fun(*this,
        &amp;Example_TreeView_TreeStore::on_cell_toggled), m_columns.dave)
);</programlisting>
</sect2>

<sect2 id="treeview-editable-cells">
<title>Cellules modifiables</title>

<sect3 id="treeview-editable-cells-automatic">
<title>Cellules modifiables à enregistrement automatique.</title>
<para lang="en">
Cells in a <classname>TreeView</classname> can be edited in-place by the user.
To allow this, use the <classname>Gtk::TreeView</classname>
<methodname>insert_column_editable()</methodname> and
<methodname>append_column_editable()</methodname> methods instead of
<methodname>insert_column()</methodname> and <methodname>append_column()</methodname>.
When these cells are edited the new values will be stored immediately in the
Model. Note that these methods are templates which can only be instantiated for
simple column types such as <classname>Glib::ustring</classname>, int, and
long.
</para>
</sect3>

<sect3 id="treeview-editable-cells-custom">
<title>Implémentation d'une logique personnalisée pour les cellules modifiables.</title>
<para>Toutefois, vous pouvez vouloir que les nouvelles valeurs ne soient pas immédiatement enregistrées. Vous voulez, par exemple, limiter la saisie à certains caractères ou plages de valeurs.</para>
<para lang="en">
To achieve this, you should use the normal <classname>Gtk::TreeView</classname>
<methodname>insert_column()</methodname> and <methodname>append_column()</methodname>
methods, then use <methodname>get_column_cell_renderer()</methodname> to get the
<classname>Gtk::CellRenderer</classname> used by that column.
</para>
<para>Ensuite vous ferez un forçage du type de ce pointeur <classname>Gtk::CellRenderer*</classname> vers un <classname>CellRenderer</classname> donné, conforme à vos attentes. Vous utilisez ainsi une API particulière.</para>
<para>Par exemple, pour un CellRendererText, vous définissez la propriété <emphasis>editable</emphasis> égale à <literal>true</literal>, comme ceci :</para>
<programlisting>cell.property_editable() = true;</programlisting>
<para>Pour un « CellRendererToggle », vous paramétrez la propriété <emphasis>activatable</emphasis> à la place.</para>
<para>Vous pouvez alors connecter le signal « edited » approprié, par exemple, connecter à <methodname>Gtk::CellRendererText::signal_edited()</methodname> ou <methodname>Gtk::CellRendererToggle::signal_toggled()</methodname>. Si la colonne comprend plus d'un <classname>CellRenderer</classname>, vous aurez besoin d'utiliser <methodname>Gtk::TreeView::get_column()</methodname>, puis d'appeler <methodname>get_cell_renderers()</methodname> sur cette colonne de la vue.</para>
<para>Dans le gestionnaire de signal, vous devriez examiner la nouvelle valeur et l'enregistrer dans le modèle si vous la jugez appropriée pour l'application.</para>
</sect3>

</sect2>


</sect1>

<sect1 id="sec-iterating-over-model-rows">
<title>Itération parmi les colonnes du modèle</title>
<para><classname>Gtk::TreeModel</classname> fournit un conteneur dans le style de la bibliothèque standard C++ pour ses enfants par l'intermédiaire de la fonction membre <methodname>children()</methodname>. Vous pouvez utiliser les fonctions membres habituelles <methodname>begin()</methodname> et <methodname>end()</methodname> pour incrémenter un itérateur, comme ceci :</para>
<programlisting>typedef Gtk::TreeModel::Children type_children; // minimise la longueur du code.
type_children children = refModel-&gt;children();
for(type_children::iterator iter = children.begin();
    iter != children.end(); ++iter)
{
  Gtk::TreeModel::Row row = *iter;
  // Faire quelque chose avec la ligne - voir plus haut pour set/get.
}</programlisting>

<sect2 id="treeview-row-children">
<title>Ligne enfant</title>
<para lang="en">
When using a <classname>Gtk::TreeStore</classname>, the rows can have child
rows, which can have their own children in turn. Use
<methodname>Gtk::TreeModel::Row::children()</methodname> to get the container of child <classname>Row</classname>s:
<programlisting lang="en">Gtk::TreeModel::Children children = row.children();</programlisting>
</para>
</sect2>

</sect1>

<sect1 id="sec-treeview-selection">
<title>La sélection</title>
<para>Pour retrouver quelles sont les lignes sélectionnées par l'utilisateur, obtenez l'objet <classname>Gtk::TreeView::Selection</classname> du <classname>TreeView</classname> ainsi :</para>
<programlisting>Glib::RefPtr&lt;Gtk::TreeSelection&gt; refTreeSelection =
    m_TreeView.get_selection();</programlisting>

<sect2 id="treeview-selection-mode">
<title>Sélection simple ou multiple</title>
<para lang="en">
By default, only single rows can be selected, but you can allow
multiple selection by setting the mode, like so:
<programlisting lang="en">refTreeSelection-&gt;set_mode(Gtk::SELECTION_MULTIPLE);</programlisting>
</para>
</sect2>

<sect2 id="treeview-selected-rows">
<title>Les lignes sélectionnées</title>
<para>Pour une simple sélection, appelez simplement la fonction membre <methodname>get_selected()</methodname>, comme suit :</para>
<programlisting>TreeModel::iterator iter = refTreeSelection-&gt;get_selected();
if(iter) // si quelque chose est sélectionné
{
  TreeModel::Row row = *iter;
  // Faire quelque chose avec la ligne.
}</programlisting>

<para>Pour une sélection multiple, vous aurez besoin de définir une fonction de rappel et de la fournir en paramètre à <methodname>selected_foreach()</methodname>, <methodname>selected_foreach_path()</methodname> ou <methodname>selected_foreach_iter()</methodname>, ainsi :</para>
<programlisting>refTreeSelection-&gt;selected_foreach_iter(
    sigc::mem_fun(*this, &amp;TheClass::selected_row_callback) );

void TheClass::selected_row_callback(
    const Gtk::TreeModel::iterator&amp; iter)
{
  TreeModel::Row row = *iter;
  // Faire quelque chose avec la ligne.
}</programlisting>

</sect2>

<sect2 id="treeview-selection-changed-signal">
<title>Le signal « changed »</title>
<para>Pour répondre à l'utilisateur qui clique sur une ligne ou une plage de lignes, connectez le signal ainsi :</para>
<programlisting lang="en">refTreeSelection-&gt;signal_changed().connect(
    sigc::mem_fun(*this, &amp;Example_IconTheme::on_selection_changed)
);</programlisting>
</sect2>

<sect2 id="treeview-selection-preventing">
<title>Empêcher la sélection de lignes</title>
<para>Il est possible que l'utilisateur n'ait pas le droit de sélectionner tous les éléments d'une liste ou d'une arborescence. Ainsi, dans le programme gtk-demo, vous pouvez choisir un exemple pour voir le code source, mais choisir une catégorie d'exemples n'a pas de sens.</para>
<para>Pour contrôler quelles lignes peuvent être sélectionnées, utilisez la fonction membre <methodname>set_select_function()</methodname> et passez lui en paramètre un signal de rappel <classname>sigc::slot</classname>. Par exemple :</para>
<programlisting>m_refTreeSelection-&gt;set_select_function( sigc::mem_fun(*this,
    &amp;DemoWindow::select_function) );</programlisting>
<para>puis</para>
<programlisting>bool DemoWindow::select_function(
    const Glib::RefPtr&lt;Gtk::TreeModel&gt;&amp; model,
    const Gtk::TreeModel::Path&amp; path, bool)
{
  const Gtk::TreeModel::iterator iter = model-&gt;get_iter(path);
  // n'autoriser que la sélection des nœuds d'extrémité
  return iter-&gt;children().empty(); 
}</programlisting>
</sect2>

<sect2 id="treeview-selection-changing">
<title>Modification de la sélection</title>
<para>Pour modifier la sélection, précisez un <classname>Gtk::TreeModel::iterator</classname> ou <classname>Gtk::TreeModel::Row</classname>, ainsi :</para>
<programlisting>Gtk::TreeModel::Row row = m_refModel-&gt;children()[5]; // 5ième ligne.
if(row)
  refTreeSelection-&gt;select(row);</programlisting>
<para>ou</para>
<programlisting>Gtk::TreeModel::iterator iter = m_refModel-&gt;children().begin()
if(iter)
  refTreeSelection-&gt;select(iter);</programlisting>
</sect2>

</sect1>


<sect1 id="sec-treeview-sort">
<title>Tris</title>
<para lang="en">
The standard tree models (<classname>TreeStore</classname> and <classname>ListStore</classname>) derive from <classname>TreeSortable</classname>, so they offer sorting functionality. For instance, call <methodname>set_sort_column()</methodname>, to sort the model by the specified column. Or supply a callback function to <methodname>set_sort_func()</methodname> to implement a more complicated sorting algorithm.
</para>

<para lang="en"><ulink url="http://developer.gnome.org/gtkmm/3.22/classGtk_1_1TreeSortable.html">TreeSortable Reference</ulink></para>

<sect2 id="treeview-sort-headers">
<title>Tri en cliquant sur l'en-tête de colonne</title>
<para lang="en">
So that a user can click on a <classname>TreeView</classname>'s column header to sort the <classname>TreeView</classname>'s contents, call <methodname>Gtk::TreeView::Column::set_sort_column()</methodname>, supplying the model column on which model should be sorted when the header is clicked. For instance:
</para>
<programlisting>Gtk::TreeView::Column* pColumn = treeview.get_column(0);
if(pColumn)
  pColumn-&gt;set_sort_column(m_columns.m_col_id);</programlisting>
</sect2>

<sect2 id="treeview-sort-independent-views">
<title>Vues d'un même modèle triées de manière indépendante</title>
<para>Nous avons déjà vu que la classe <classname>TreeView</classname> vous permet d'afficher le même <classname>TreeModel</classname> dans deux éléments graphiques <classname>TreeView</classname> distincts. Si vous avez besoin qu'un des TreeView trie le modèle de manière différente de l'autre, vous devez utiliser un objet <classname>TreeModelSort</classname> au lieu d'utiliser uniquement <methodname>Gtk::TreeViewModel::set_sort_column()</methodname>, par exemple. <classname>TreeModelSort</classname> est un modèle contenant une version triée d'un autre modèle. Par exemple, vous pouvez ajouter une autre version triée d'un modèle à un objet <classname>TreeView</classname> ainsi :</para>
<programlisting>Glib::RefPtr&lt;Gtk::TreeModelSort&gt; sorted_model =
    Gtk::TreeModelSort::create(model);
sorted_model-&gt;set_sort_column(columns.m_col_name, Gtk::SORT_ASCENDING);
treeview.set_model(sorted_model);</programlisting>

<para>Notez, toutefois, que la vue arborescente fournit des itérateurs sur le modèle trié. Vous devez les convertir en itérateurs du modèle enfant sous-jacent pour effectuer des opérations sur ce modèle. Par exemple :</para>
<programlisting>void ExampleWindow::on_button_delete()
{
  Glib::RefPtr&lt;Gtk::TreeSelection&gt; refTreeSelection =
      m_treeview.get_selection();
  if(refTreeSelection)
  {
    Gtk::TreeModel::iterator sorted_iter =
        m_refTreeSelection-&gt;get_selected();
    if(sorted_iter)
    {
      Gtk::TreeModel::iterator iter =
          m_refModelSort-&gt;convert_iter_to_child_iter(sorted_iter);
      m_refModel-&gt;erase(iter);
    }
  }
}</programlisting>

<para lang="en"><ulink url="http://developer.gnome.org/gtkmm/3.22/classGtk_1_1TreeModelSort.html">TreeModelSort Reference</ulink></para>
</sect2>

</sect1>

<sect1 id="sec-treeview-draganddrop">
<title>Glisser-déposer</title>
<para lang="en">
<classname>Gtk::TreeView</classname> already implements simple drag-and-drop
when used with the <classname>Gtk::ListStore</classname> or
<classname>Gtk::TreeStore</classname> models. If necessary, it also allows you
to implement more complex behaviour when items are dragged and dropped, using
the normal <link linkend="chapter-draganddrop">Drag and Drop</link> API.
</para>

<sect2 id="treeview-reorderable-rows">
<title>Réarrangement de lignes</title>
<para>Si vous faites appel à la fonction membre <methodname>Gtk::TreeView::set_reorderable()</methodname>, les éléments d'un objet TreeView peuvent être déplacés au sein même de la vue arborescente. Ceci est montré dans l'exemple <classname>TreeStore</classname>.</para>
<para lang="en">However, this does not allow you any control of which items can be dragged, and where they can be dropped. If you need that extra control then you might create a derived <literal>Gtk::TreeModel</literal> from <literal>Gtk::TreeStore</literal> or <literal>Gtk::ListStore</literal> and override the <literal>Gtk::TreeDragSource::row_draggable()</literal> and <literal>Gdk::TreeDragDest::row_drop_possible()</literal> virtual methods. You can examine the <literal>Gtk::TreeModel::Path</literal>s provided and allow or disallow dragging or dropping by returning <literal>true</literal> or <literal>false</literal>.</para>
<para>Cette construction est montrée dans l'exemple du glisser-déposer.</para>
</sect2>

</sect1>

<sect1 id="sec-treeview-contextmenu">
<title>Menu contextuel</title>
<para>Nombre de programmeurs ont besoin d'implémenter des menus contextuels s'ouvrant d'un clic droit de souris sur des objets <classname>TreeView</classname>. Pour vous faire gagner du temps, nous allons expliquer ici comment faire. À un ou deux points près, cela ressemble tout à fait à un menu contextuel normal tel que décrit dans le <link linkend="sec-menus-popup">chapitre Menus</link>.</para>

<sect2 id="treeview-button-press-event">
<title>Gestion du signal <literal>button_press_event</literal></title>
<para lang="en">
To detect a click of the right mouse button, you need to handle the
<literal>button_press_event</literal> signal, and check exactly which button
was pressed. Because the <classname>TreeView</classname> normally handles this
signal completely, you need to either override the default signal handler in a
derived <classname>TreeView</classname> class, or use
<methodname>connect_notify()</methodname> instead of <methodname>connect()</methodname>.
You probably also want to call the default handler before doing anything else,
so that the right-click will cause the row to be selected first.
</para>
<para lang="en">This is demonstrated in the Popup Context Menu example.</para>
</sect2>

</sect1>

<sect1 id="sec-treeview-examples"><title>Exemples</title>

<sect2 id="liststore-example"><title>ListStore</title>
<para>Voici un exemple d'élément graphique <classname>Gtk::TreeView</classname> avec un modèle <classname>Gtk::ListStore</classname>.</para>


<figure id="figure-treeview-liststore">
  <title>TreeView - ListStore</title>
  <screenshot>
    <graphic format="PNG" fileref="figures/treeview_list.png"/>
  </screenshot>
</figure>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/treeview/list/?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>examplewindow.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLEWINDOW_H
#define GTKMM_EXAMPLEWINDOW_H

#include &lt;gtkmm.h&gt;

class ExampleWindow : public Gtk::Window
{
public:
  ExampleWindow();
  virtual ~ExampleWindow();

protected:
  //Signal handlers:
  void on_button_quit();

  //Tree model columns:
  class ModelColumns : public Gtk::TreeModel::ColumnRecord
  {
  public:

    ModelColumns()
    { add(m_col_id); add(m_col_name); add(m_col_number); add(m_col_percentage);}

    Gtk::TreeModelColumn&lt;unsigned int&gt; m_col_id;
    Gtk::TreeModelColumn&lt;Glib::ustring&gt; m_col_name;
    Gtk::TreeModelColumn&lt;short&gt; m_col_number;
    Gtk::TreeModelColumn&lt;int&gt; m_col_percentage;
  };

  ModelColumns m_Columns;

  //Child widgets:
  Gtk::Box m_VBox;

  Gtk::ScrolledWindow m_ScrolledWindow;
  Gtk::TreeView m_TreeView;
  Glib::RefPtr&lt;Gtk::ListStore&gt; m_refTreeModel;

  Gtk::ButtonBox m_ButtonBox;
  Gtk::Button m_Button_Quit;
};

#endif //GTKMM_EXAMPLEWINDOW_H
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;gtkmm/application.h&gt;

int main(int argc, char *argv[])
{
  auto app = Gtk::Application::create(argc, argv, "org.gtkmm.example");

  ExampleWindow window;

  //Shows the window and returns when it is closed.
  return app-&gt;run(window);
}
</programlisting>
<para lang="en">File: <filename>examplewindow.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include &lt;iostream&gt;
#include "examplewindow.h"

ExampleWindow::ExampleWindow()
: m_VBox(Gtk::ORIENTATION_VERTICAL),
  m_Button_Quit("Quit")
{
  set_title("Gtk::TreeView (ListStore) example");
  set_border_width(5);
  set_default_size(400, 200);

  add(m_VBox);

  //Add the TreeView, inside a ScrolledWindow, with the button underneath:
  m_ScrolledWindow.add(m_TreeView);

  //Only show the scrollbars when they are necessary:
  m_ScrolledWindow.set_policy(Gtk::POLICY_AUTOMATIC, Gtk::POLICY_AUTOMATIC);

  m_VBox.pack_start(m_ScrolledWindow);
  m_VBox.pack_start(m_ButtonBox, Gtk::PACK_SHRINK);

  m_ButtonBox.pack_start(m_Button_Quit, Gtk::PACK_SHRINK);
  m_ButtonBox.set_border_width(5);
  m_ButtonBox.set_layout(Gtk::BUTTONBOX_END);
  m_Button_Quit.signal_clicked().connect( sigc::mem_fun(*this,
              &amp;ExampleWindow::on_button_quit) );

  //Create the Tree model:
  m_refTreeModel = Gtk::ListStore::create(m_Columns);
  m_TreeView.set_model(m_refTreeModel);

  //Fill the TreeView's model
  Gtk::TreeModel::Row row = *(m_refTreeModel-&gt;append());
  row[m_Columns.m_col_id] = 1;
  row[m_Columns.m_col_name] = "Billy Bob";
  row[m_Columns.m_col_number] = 10;
  row[m_Columns.m_col_percentage] = 15;

  row = *(m_refTreeModel-&gt;append());
  row[m_Columns.m_col_id] = 2;
  row[m_Columns.m_col_name] = "Joey Jojo";
  row[m_Columns.m_col_number] = 20;
  row[m_Columns.m_col_percentage] = 40;

  row = *(m_refTreeModel-&gt;append());
  row[m_Columns.m_col_id] = 3;
  row[m_Columns.m_col_name] = "Rob McRoberts";
  row[m_Columns.m_col_number] = 30;
  row[m_Columns.m_col_percentage] = 70;

  //Add the TreeView's view columns:
  //This number will be shown with the default numeric formatting.
  m_TreeView.append_column("ID", m_Columns.m_col_id);
  m_TreeView.append_column("Name", m_Columns.m_col_name);

  m_TreeView.append_column_numeric("Formatted number", m_Columns.m_col_number,
          "%010d" /* 10 digits, using leading zeroes. */);

  //Display a progress bar instead of a decimal number:
  auto cell = Gtk::manage(new Gtk::CellRendererProgress);
  int cols_count = m_TreeView.append_column("Some percentage", *cell);
  auto pColumn = m_TreeView.get_column(cols_count - 1);
  if(pColumn)
  {
    pColumn-&gt;add_attribute(cell-&gt;property_value(), m_Columns.m_col_percentage);
  }

  //Make all the columns reorderable:
  //This is not necessary, but it's nice to show the feature.
  //You can use TreeView::set_column_drag_function() to more
  //finely control column drag and drop.
  for(guint i = 0; i &lt; 2; i++)
  {
    auto column = m_TreeView.get_column(i);
    column-&gt;set_reorderable();
  }

  show_all_children();
}

ExampleWindow::~ExampleWindow()
{
}

void ExampleWindow::on_button_quit()
{
  hide();
}

</programlisting>
<!-- end inserted example code -->

</sect2>

<sect2 id="treestore-example"><title>TreeStore</title>

<para>C'est exemple est tout à fait semblable au précédent, mais il utilise un modèle <classname>Gtk::TreeStore</classname> à la place et il ajoute des enfants aux colonnes.</para>

<figure id="figure-treeview-treestore">
  <title>TreeView - TreeStore</title>
  <screenshot>
    <graphic format="PNG" fileref="figures/treeview_tree.png"/>
  </screenshot>
</figure>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/treeview/tree/?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>examplewindow.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLEWINDOW_H
#define GTKMM_EXAMPLEWINDOW_H

#include &lt;gtkmm.h&gt;

class ExampleWindow : public Gtk::Window
{
public:
  ExampleWindow();
  virtual ~ExampleWindow();

protected:
  //Signal handlers:
  void on_button_quit();
  void on_treeview_row_activated(const Gtk::TreeModel::Path&amp; path, Gtk::TreeViewColumn* column);

  //Tree model columns:
  class ModelColumns : public Gtk::TreeModel::ColumnRecord
  {
  public:

    ModelColumns()
    { add(m_col_id); add(m_col_name); }

    Gtk::TreeModelColumn&lt;int&gt; m_col_id;
    Gtk::TreeModelColumn&lt;Glib::ustring&gt; m_col_name;
  };

  ModelColumns m_Columns;

  //Child widgets:
  Gtk::Box m_VBox;

  Gtk::ScrolledWindow m_ScrolledWindow;
  Gtk::TreeView m_TreeView;
  Glib::RefPtr&lt;Gtk::TreeStore&gt; m_refTreeModel;

  Gtk::ButtonBox m_ButtonBox;
  Gtk::Button m_Button_Quit;
};

#endif //GTKMM_EXAMPLEWINDOW_H
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;gtkmm/application.h&gt;

int main(int argc, char *argv[])
{
  auto app = Gtk::Application::create(argc, argv, "org.gtkmm.example");

  ExampleWindow window;

  //Shows the window and returns when it is closed.
  return app-&gt;run(window);
}
</programlisting>
<para lang="en">File: <filename>examplewindow.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include &lt;iostream&gt;
#include "examplewindow.h"

ExampleWindow::ExampleWindow()
: m_VBox(Gtk::ORIENTATION_VERTICAL),
  m_Button_Quit("Quit")
{
  set_title("Gtk::TreeView (TreeStore) example");
  set_border_width(5);
  set_default_size(400, 200);

  add(m_VBox);

  //Add the TreeView, inside a ScrolledWindow, with the button underneath:
  m_ScrolledWindow.add(m_TreeView);

  //Only show the scrollbars when they are necessary:
  m_ScrolledWindow.set_policy(Gtk::POLICY_AUTOMATIC, Gtk::POLICY_AUTOMATIC);

  m_VBox.pack_start(m_ScrolledWindow);
  m_VBox.pack_start(m_ButtonBox, Gtk::PACK_SHRINK);

  m_ButtonBox.pack_start(m_Button_Quit, Gtk::PACK_SHRINK);
  m_ButtonBox.set_border_width(5);
  m_ButtonBox.set_layout(Gtk::BUTTONBOX_END);
  m_Button_Quit.signal_clicked().connect(sigc::mem_fun(*this,
              &amp;ExampleWindow::on_button_quit) );

  //Create the Tree model:
  m_refTreeModel = Gtk::TreeStore::create(m_Columns);
  m_TreeView.set_model(m_refTreeModel);

  //All the items to be reordered with drag-and-drop:
  m_TreeView.set_reorderable();

  //Fill the TreeView's model
  Gtk::TreeModel::Row row = *(m_refTreeModel-&gt;append());
  row[m_Columns.m_col_id] = 1;
  row[m_Columns.m_col_name] = "Billy Bob";

  Gtk::TreeModel::Row childrow = *(m_refTreeModel-&gt;append(row.children()));
  childrow[m_Columns.m_col_id] = 11;
  childrow[m_Columns.m_col_name] = "Billy Bob Junior";

  childrow = *(m_refTreeModel-&gt;append(row.children()));
  childrow[m_Columns.m_col_id] = 12;
  childrow[m_Columns.m_col_name] = "Sue Bob";

  row = *(m_refTreeModel-&gt;append());
  row[m_Columns.m_col_id] = 2;
  row[m_Columns.m_col_name] = "Joey Jojo";


  row = *(m_refTreeModel-&gt;append());
  row[m_Columns.m_col_id] = 3;
  row[m_Columns.m_col_name] = "Rob McRoberts";

  childrow = *(m_refTreeModel-&gt;append(row.children()));
  childrow[m_Columns.m_col_id] = 31;
  childrow[m_Columns.m_col_name] = "Xavier McRoberts";

  //Add the TreeView's view columns:
  m_TreeView.append_column("ID", m_Columns.m_col_id);
  m_TreeView.append_column("Name", m_Columns.m_col_name);

  //Connect signal:
  m_TreeView.signal_row_activated().connect(sigc::mem_fun(*this,
              &amp;ExampleWindow::on_treeview_row_activated) );

  show_all_children();
}

ExampleWindow::~ExampleWindow()
{
}

void ExampleWindow::on_button_quit()
{
  hide();
}

void ExampleWindow::on_treeview_row_activated(const Gtk::TreeModel::Path&amp; path,
        Gtk::TreeViewColumn* /* column */)
{
  Gtk::TreeModel::iterator iter = m_refTreeModel-&gt;get_iter(path);
  if(iter)
  {
    Gtk::TreeModel::Row row = *iter;
    std::cout &lt;&lt; "Row activated: ID=" &lt;&lt; row[m_Columns.m_col_id] &lt;&lt; ", Name="
        &lt;&lt; row[m_Columns.m_col_name] &lt;&lt; std::endl;
  }
}

</programlisting>
<!-- end inserted example code -->

</sect2>

<sect2 id="sec-editable-cells-example"><title>Cellules modifiables</title>

<para>Cet exemple est identique à l'exemple avec <classname>ListStore</classname>, mais il utilise <methodname>TreeView::append_column_editable()</methodname> à la place de <methodname>TreeView::append_column()</methodname>.</para>

<figure id="figure-treeview-editablecells">
  <title>TreeView - Cellules modifiables</title>
  <screenshot>
    <graphic format="PNG" fileref="figures/treeview_editablecells.png"/>
  </screenshot>
</figure>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/treeview/editable_cells/?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>examplewindow.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLEWINDOW_H
#define GTKMM_EXAMPLEWINDOW_H

#include &lt;gtkmm.h&gt;

class ExampleWindow : public Gtk::Window
{
public:
  ExampleWindow();
  virtual ~ExampleWindow();

protected:
  //Signal handlers:
  void on_button_quit();

  void treeviewcolumn_validated_on_cell_data(Gtk::CellRenderer* renderer, const Gtk::TreeModel::iterator&amp; iter);
  void cellrenderer_validated_on_editing_started(Gtk::CellEditable* cell_editable, const Glib::ustring&amp; path);
  void cellrenderer_validated_on_edited(const Glib::ustring&amp; path_string, const Glib::ustring&amp; new_text);

  //Tree model columns:
  class ModelColumns : public Gtk::TreeModel::ColumnRecord
  {
  public:

    ModelColumns()
    { add(m_col_id); add(m_col_name); add(m_col_foo); add(m_col_number); add(m_col_number_validated); }

    Gtk::TreeModelColumn&lt;unsigned int&gt; m_col_id;
    Gtk::TreeModelColumn&lt;Glib::ustring&gt; m_col_name;
    Gtk::TreeModelColumn&lt;bool&gt; m_col_foo;
    Gtk::TreeModelColumn&lt;int&gt; m_col_number;
    Gtk::TreeModelColumn&lt;int&gt; m_col_number_validated;
  };

  ModelColumns m_Columns;

  //Child widgets:
  Gtk::Box m_VBox;

  Gtk::ScrolledWindow m_ScrolledWindow;
  Gtk::TreeView m_TreeView;
  Glib::RefPtr&lt;Gtk::ListStore&gt; m_refTreeModel;

  Gtk::ButtonBox m_ButtonBox;
  Gtk::Button m_Button_Quit;

  //For the validated column:
  //You could also use a CellRendererSpin or a CellRendererProgress:
  Gtk::CellRendererText m_cellrenderer_validated;
  Gtk::TreeView::Column m_treeviewcolumn_validated;
  bool m_validate_retry;
  Glib::ustring m_invalid_text_for_retry;
};

#endif //GTKMM_EXAMPLEWINDOW_H
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;gtkmm/application.h&gt;

int main(int argc, char *argv[])
{
  auto app = Gtk::Application::create(argc, argv, "org.gtkmm.example");

  ExampleWindow window;

  //Shows the window and returns when it is closed.
  return app-&gt;run(window);
}
</programlisting>
<para lang="en">File: <filename>examplewindow.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include &lt;iostream&gt;
#include &lt;cstdio&gt;
#include &lt;cstdlib&gt;
#include "examplewindow.h"

using std::sprintf;
using std::strtol;

ExampleWindow::ExampleWindow()
: m_VBox(Gtk::ORIENTATION_VERTICAL),
  m_Button_Quit("Quit"),
  m_validate_retry(false)
{
  set_title("Gtk::TreeView Editable Cells example");
  set_border_width(5);
  set_default_size(400, 200);


  add(m_VBox);

  //Add the TreeView, inside a ScrolledWindow, with the button underneath:
  m_ScrolledWindow.add(m_TreeView);

  //Only show the scrollbars when they are necessary:
  m_ScrolledWindow.set_policy(Gtk::POLICY_AUTOMATIC, Gtk::POLICY_AUTOMATIC);

  m_VBox.pack_start(m_ScrolledWindow);
  m_VBox.pack_start(m_ButtonBox, Gtk::PACK_SHRINK);

  m_ButtonBox.pack_start(m_Button_Quit, Gtk::PACK_SHRINK);
  m_ButtonBox.set_border_width(5);
  m_ButtonBox.set_layout(Gtk::BUTTONBOX_END);
  m_Button_Quit.signal_clicked().connect( sigc::mem_fun(*this,
              &amp;ExampleWindow::on_button_quit) );

  //Create the Tree model:
  m_refTreeModel = Gtk::ListStore::create(m_Columns);
  m_TreeView.set_model(m_refTreeModel);

  //Fill the TreeView's model
  Gtk::TreeModel::Row row = *(m_refTreeModel-&gt;append());
  row[m_Columns.m_col_id] = 1;
  row[m_Columns.m_col_name] = "Billy Bob";
  row[m_Columns.m_col_foo] = true;
  row[m_Columns.m_col_number] = 10;

  row = *(m_refTreeModel-&gt;append());
  row[m_Columns.m_col_id] = 2;
  row[m_Columns.m_col_name] = "Joey Jojo";
  row[m_Columns.m_col_foo] = true;
  row[m_Columns.m_col_number] = 20;

  row = *(m_refTreeModel-&gt;append());

  row[m_Columns.m_col_id] = 3;
  row[m_Columns.m_col_name] = "Rob McRoberts";
  row[m_Columns.m_col_foo] = false;
  row[m_Columns.m_col_number] = 30;

  //Add the TreeView's view columns:
  //We use the *_editable convenience methods for most of these,
  //because the default functionality is enough:
  m_TreeView.append_column_editable("ID", m_Columns.m_col_id);
  m_TreeView.append_column_editable("Name", m_Columns.m_col_name);
  m_TreeView.append_column_editable("foo", m_Columns.m_col_foo);
  m_TreeView.append_column_numeric_editable("foo", m_Columns.m_col_number,
          "%010d");


  //For this column, we create the CellRenderer ourselves, and connect our own
  //signal handlers, so that we can validate the data that the user enters, and
  //control how it is displayed.
  m_treeviewcolumn_validated.set_title("validated (&lt;10)");
  m_treeviewcolumn_validated.pack_start(m_cellrenderer_validated);
  m_TreeView.append_column(m_treeviewcolumn_validated);

  //Tell the view column how to render the model values:
  m_treeviewcolumn_validated.set_cell_data_func(m_cellrenderer_validated,
          sigc::mem_fun(*this,
              &amp;ExampleWindow::treeviewcolumn_validated_on_cell_data) );

  //Make the CellRenderer editable, and handle its editing signals:
  m_cellrenderer_validated.property_editable() = true;

  m_cellrenderer_validated.signal_editing_started().connect(
          sigc::mem_fun(*this,
        &amp;ExampleWindow::cellrenderer_validated_on_editing_started) );

  m_cellrenderer_validated.signal_edited().connect( sigc::mem_fun(*this,
              &amp;ExampleWindow::cellrenderer_validated_on_edited) );

  //If this was a CellRendererSpin then you would have to set the adjustment:
  //m_cellrenderer_validated.property_adjustment() = m_spin_adjustment;

  show_all_children();
}

ExampleWindow::~ExampleWindow()
{
}

void ExampleWindow::on_button_quit()
{
  hide();
}

void ExampleWindow::treeviewcolumn_validated_on_cell_data(
        Gtk::CellRenderer* /* renderer */,
        const Gtk::TreeModel::iterator&amp; iter)
{
  //Get the value from the model and show it appropriately in the view:
  if(iter)
  {
    Gtk::TreeModel::Row row = *iter;
    int model_value = row[m_Columns.m_col_number_validated];

    //This is just an example.
    //In this case, it would be easier to use append_column_editable() or
    //append_column_numeric_editable()
    char buffer[32];
    sprintf(buffer, "%d", model_value);

    Glib::ustring view_text = buffer;
    m_cellrenderer_validated.property_text() = view_text;
  }
}

void ExampleWindow::cellrenderer_validated_on_editing_started(
        Gtk::CellEditable* cell_editable, const Glib::ustring&amp; /* path */)
{
  //Start editing with previously-entered (but invalid) text,
  //if we are allowing the user to correct some invalid data.
  if(m_validate_retry)
  {
    //This is the CellEditable inside the CellRenderer.
    auto celleditable_validated = cell_editable;

    //It's usually an Entry, at least for a CellRendererText:
    auto pEntry = dynamic_cast&lt;Gtk::Entry*&gt;(celleditable_validated);
    if(pEntry)
    {
      pEntry-&gt;set_text(m_invalid_text_for_retry);
      m_validate_retry = false;
      m_invalid_text_for_retry.clear();
    }
  }

}

void ExampleWindow::cellrenderer_validated_on_edited(
        const Glib::ustring&amp; path_string,
        const Glib::ustring&amp; new_text)
{
  Gtk::TreePath path(path_string);

  //Convert the inputed text to an integer, as needed by our model column:
  char* pchEnd = nullptr;
  int new_value = strtol(new_text.c_str(), &amp;pchEnd, 10);

  if(new_value &gt; 10)
  {
    //Prevent entry of numbers higher than 10.

    //Tell the user:
    Gtk::MessageDialog dialog(*this,
            "The number must be less than 10. Please try again.",
            false, Gtk::MESSAGE_ERROR);
    dialog.run();

    //Start editing again, with the bad text, so that the user can correct it.
    //A real application should probably allow the user to revert to the
    //previous text.

    //Set the text to be used in the start_editing signal handler:
    m_invalid_text_for_retry = new_text;
    m_validate_retry = true;

    //Start editing again:
    m_TreeView.set_cursor(path, m_treeviewcolumn_validated,
            m_cellrenderer_validated, true /* start_editing */);
  }
  else
  {
    //Get the row from the path:
    Gtk::TreeModel::iterator iter = m_refTreeModel-&gt;get_iter(path);
    if(iter)
    {
      Gtk::TreeModel::Row row = *iter;

      //Put the new value in the model:
      row[m_Columns.m_col_number_validated] = new_value;
    }
  }
}

</programlisting>
<!-- end inserted example code -->

</sect2>

<sect2 id="treeview-dnd-example"><title>Glisser-déposer</title>

<para lang="en">
This example is much like the <classname>TreeStore</classname> example, but has
2 extra columns to indicate whether the row can be dragged, and whether it can
receive drag-and-dropped rows. It uses a derived
<classname>Gtk::TreeStore</classname> which overrides the virtual functions as
described in the <link linkend="sec-treeview-draganddrop">TreeView Drag and
    Drop</link> section.
</para>

<figure id="figure-treeview-draganddrop">
  <title>TreeView - Glisser-déposer</title>
  <screenshot>
    <graphic format="PNG" fileref="figures/treeview_draganddrop.png"/>
  </screenshot>
</figure>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/treeview/drag_and_drop/?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>treemodel_dnd.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLE_TREEMODEL_DND_H
#define GTKMM_EXAMPLE_TREEMODEL_DND_H

#include &lt;gtkmm.h&gt;

class TreeModel_Dnd : public Gtk::TreeStore
{
protected:
  TreeModel_Dnd();

public:

  //Tree model columns:
  class ModelColumns : public Gtk::TreeModel::ColumnRecord
  {
  public:

    ModelColumns()
    { add(m_col_id); add(m_col_name); add(m_col_draggable); add(m_col_receivesdrags); }

    Gtk::TreeModelColumn&lt;int&gt; m_col_id;
    Gtk::TreeModelColumn&lt;Glib::ustring&gt; m_col_name;
    Gtk::TreeModelColumn&lt;bool&gt; m_col_draggable;
    Gtk::TreeModelColumn&lt;bool&gt; m_col_receivesdrags;
  };

  ModelColumns m_Columns;

  static Glib::RefPtr&lt;TreeModel_Dnd&gt; create();

protected:
  //Overridden virtual functions:
  bool row_draggable_vfunc(const Gtk::TreeModel::Path&amp; path) const override;
  bool row_drop_possible_vfunc(const Gtk::TreeModel::Path&amp; dest, const Gtk::SelectionData&amp; selection_data) const override;

};

#endif //GTKMM_EXAMPLE_TREEMODEL_DND_H
</programlisting>
<para lang="en">File: <filename>examplewindow.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLEWINDOW_H
#define GTKMM_EXAMPLEWINDOW_H

#include &lt;gtkmm.h&gt;
#include "treemodel_dnd.h"


class ExampleWindow : public Gtk::Window
{
public:
  ExampleWindow();
  virtual ~ExampleWindow();

protected:
  //Signal handlers:
  void on_button_quit();


  //Child widgets:
  Gtk::Box m_VBox;

  Gtk::ScrolledWindow m_ScrolledWindow;
  Gtk::TreeView m_TreeView;
  Glib::RefPtr&lt;TreeModel_Dnd&gt; m_refTreeModel;

  Gtk::ButtonBox m_ButtonBox;
  Gtk::Button m_Button_Quit;
};

#endif //GTKMM_EXAMPLEWINDOW_H
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;gtkmm/application.h&gt;

int main(int argc, char *argv[])
{
  auto app = Gtk::Application::create(argc, argv, "org.gtkmm.example");

  ExampleWindow window;

  //Shows the window and returns when it is closed.
  return app-&gt;run(window);
}
</programlisting>
<para lang="en">File: <filename>treemodel_dnd.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "treemodel_dnd.h"
#include &lt;iostream&gt;

TreeModel_Dnd::TreeModel_Dnd()
{
  //We can't just call Gtk::TreeModel(m_Columns) in the initializer list
  //because m_Columns does not exist when the base class constructor runs.
  //And we can't have a static m_Columns instance, because that would be
  //instantiated before the gtkmm type system.
  //So, we use this method, which should only be used just after creation:
  set_column_types(m_Columns);
}

Glib::RefPtr&lt;TreeModel_Dnd&gt; TreeModel_Dnd::create()
{
  return Glib::RefPtr&lt;TreeModel_Dnd&gt;( new TreeModel_Dnd() );
}

bool
TreeModel_Dnd::row_draggable_vfunc(const Gtk::TreeModel::Path&amp; path) const
{
  // Make the value of the "draggable" column determine whether this row can
  // be dragged:

  //TODO: Add a const version of get_iter to TreeModel:
  auto unconstThis = const_cast&lt;TreeModel_Dnd*&gt;(this);
  const_iterator iter = unconstThis-&gt;get_iter(path);
  //const_iterator iter = get_iter(path);
  if(iter)
  {
    Row row = *iter;
    bool is_draggable = row[m_Columns.m_col_draggable];
    return is_draggable;
  }

  return Gtk::TreeStore::row_draggable_vfunc(path);
}

bool
TreeModel_Dnd::row_drop_possible_vfunc(const Gtk::TreeModel::Path&amp; dest,
        const Gtk::SelectionData&amp; selection_data) const
{
  //Make the value of the "receives drags" column determine whether a row can be
  //dragged into it:

  //dest is the path that the row would have after it has been dropped:
  //But in this case we are more interested in the parent row:
  Gtk::TreeModel::Path dest_parent = dest;
  bool dest_is_not_top_level = dest_parent.up();
  if(!dest_is_not_top_level || dest_parent.empty())
  {
    //The user wants to move something to the top-level.
    //Let's always allow that.
  }
  else
  {
    //Get an iterator for the row at this path:
    //We must unconst this. This should not be necessary with a future version
    //of gtkmm.
    //TODO: Add a const version of get_iter to TreeModel:
    auto unconstThis = const_cast&lt;TreeModel_Dnd*&gt;(this);
    const_iterator iter_dest_parent = unconstThis-&gt;get_iter(dest_parent);
    //const_iterator iter_dest_parent = get_iter(dest);
    if(iter_dest_parent)
    {
      Row row = *iter_dest_parent;
      bool receives_drags = row[m_Columns.m_col_receivesdrags];
      return receives_drags;
    }
  }

  //You could also examine the row being dragged (via selection_data)
  //if you must look at both rows to see whether a drop should be allowed.
  //You could use
  //TODO: Add const version of get_from_selection_data(): Glib::RefPtr&lt;const
  //Gtk::TreeModel&gt; refThis = Glib::RefPtr&lt;const Gtk::TreeModel&gt;(this);
  //
  //auto refThis =
  //Glib::RefPtr&lt;Gtk::TreeModel&gt;(const_cast&lt;TreeModel_Dnd*&gt;(this));
  //refThis-&gt;reference(); //, true /* take_copy */)
  //Gtk::TreeModel::Path path_dragged_row;
  //Gtk::TreeModel::Path::get_from_selection_data(selection_data, refThis,
  //path_dragged_row);

  return Gtk::TreeStore::row_drop_possible_vfunc(dest, selection_data);
}

</programlisting>
<para lang="en">File: <filename>examplewindow.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include &lt;iostream&gt;
#include "examplewindow.h"

ExampleWindow::ExampleWindow()
: m_VBox(Gtk::ORIENTATION_VERTICAL),
  m_Button_Quit("_Quit", true)
{
  set_title("Gtk::TreeView (Drag and Drop) example");
  set_border_width(5);
  set_default_size(400, 200);

  add(m_VBox);

  //Add the TreeView, inside a ScrolledWindow, with the button underneath:
  m_ScrolledWindow.add(m_TreeView);

  //Only show the scrollbars when they are necessary:
  m_ScrolledWindow.set_policy(Gtk::POLICY_AUTOMATIC, Gtk::POLICY_AUTOMATIC);

  m_VBox.pack_start(m_ScrolledWindow);
  m_VBox.pack_start(m_ButtonBox, Gtk::PACK_SHRINK);

  m_ButtonBox.pack_start(m_Button_Quit, Gtk::PACK_SHRINK);
  m_ButtonBox.set_border_width(5);
  m_ButtonBox.set_layout(Gtk::BUTTONBOX_END);
  m_Button_Quit.signal_clicked().connect(sigc::mem_fun(*this,
              &amp;ExampleWindow::on_button_quit) );

  //Create the Tree model:
  //Use our derived model, which overrides some Gtk::TreeDragDest and
  //Gtk::TreeDragSource virtual functions:
  //The columns are declared in the overridden TreeModel.
  m_refTreeModel = TreeModel_Dnd::create();
  m_TreeView.set_model(m_refTreeModel);

  //Enable Drag-and-Drop of TreeView rows:
  //See also the derived TreeModel's *_vfunc overrides.
  m_TreeView.enable_model_drag_source();
  m_TreeView.enable_model_drag_dest();

  //Fill the TreeView's model
  Gtk::TreeModel::Row row = *(m_refTreeModel-&gt;append());
  row[m_refTreeModel-&gt;m_Columns.m_col_id] = 1;
  row[m_refTreeModel-&gt;m_Columns.m_col_name] = "Billy Bob";
  row[m_refTreeModel-&gt;m_Columns.m_col_draggable] = true;
  row[m_refTreeModel-&gt;m_Columns.m_col_receivesdrags] = true;

  Gtk::TreeModel::Row childrow = *(m_refTreeModel-&gt;append(row.children()));
  childrow[m_refTreeModel-&gt;m_Columns.m_col_id] = 11;
  childrow[m_refTreeModel-&gt;m_Columns.m_col_name] = "Billy Bob Junior";
  childrow[m_refTreeModel-&gt;m_Columns.m_col_draggable] = true;
  childrow[m_refTreeModel-&gt;m_Columns.m_col_receivesdrags] = true;

  childrow = *(m_refTreeModel-&gt;append(row.children()));
  childrow[m_refTreeModel-&gt;m_Columns.m_col_id] = 12;
  childrow[m_refTreeModel-&gt;m_Columns.m_col_name] = "Sue Bob";
  childrow[m_refTreeModel-&gt;m_Columns.m_col_draggable] = true;
  childrow[m_refTreeModel-&gt;m_Columns.m_col_receivesdrags] = true;

  row = *(m_refTreeModel-&gt;append());
  row[m_refTreeModel-&gt;m_Columns.m_col_id] = 2;
  row[m_refTreeModel-&gt;m_Columns.m_col_name] = "Joey Jojo";
  row[m_refTreeModel-&gt;m_Columns.m_col_draggable] = true;
  row[m_refTreeModel-&gt;m_Columns.m_col_receivesdrags] = true;

  row = *(m_refTreeModel-&gt;append());
  row[m_refTreeModel-&gt;m_Columns.m_col_id] = 3;
  row[m_refTreeModel-&gt;m_Columns.m_col_name] = "Rob McRoberts";
  row[m_refTreeModel-&gt;m_Columns.m_col_draggable] = true;
  row[m_refTreeModel-&gt;m_Columns.m_col_receivesdrags] = true;

  childrow = *(m_refTreeModel-&gt;append(row.children()));
  childrow[m_refTreeModel-&gt;m_Columns.m_col_id] = 31;
  childrow[m_refTreeModel-&gt;m_Columns.m_col_name] = "Xavier McRoberts";
  childrow[m_refTreeModel-&gt;m_Columns.m_col_draggable] = true;
  childrow[m_refTreeModel-&gt;m_Columns.m_col_receivesdrags] = true;

  //Add the TreeView's view columns:
  m_TreeView.append_column("ID", m_refTreeModel-&gt;m_Columns.m_col_id);
  m_TreeView.append_column("Name", m_refTreeModel-&gt;m_Columns.m_col_name);
  m_TreeView.append_column_editable("Draggable",
          m_refTreeModel-&gt;m_Columns.m_col_draggable);
  m_TreeView.append_column_editable("Receives Drags",
          m_refTreeModel-&gt;m_Columns.m_col_receivesdrags);

  show_all_children();
}

ExampleWindow::~ExampleWindow()
{
}

void ExampleWindow::on_button_quit()
{
  hide();
}

</programlisting>
<!-- end inserted example code -->

</sect2>

<sect2 id="treeview-popup-menu-example"><title>Menu contextuel</title>

<para>Cet exemple est tout à fait semblable à l'exemple <classname>ListStore</classname>, excepté qu'il crée un <classname>TreeView</classname> personnalisé par dérivation pour permettre la surdéfinition de <literal>button_press_event</literal> et pour encapsuler le code du modèle d'arborescence dans cette classe dérivée. Consultez le paragraphe <link linkend="sec-treeview-contextmenu">Menu contextuel et TreeView</link>.</para>

<figure id="figure-treeview-popup">
  <title>TreeView - Menu contextuel</title>
  <screenshot>
    <graphic format="PNG" fileref="figures/treeview_popup.png"/>
  </screenshot>
</figure>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/treeview/popup/?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>examplewindow.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLEWINDOW_H
#define GTKMM_EXAMPLEWINDOW_H

#include &lt;gtkmm.h&gt;
#include "treeview_withpopup.h"

class ExampleWindow : public Gtk::Window
{
public:
  ExampleWindow();
  virtual ~ExampleWindow();

protected:
  //Signal handlers:
  void on_button_quit();



  //Child widgets:
  Gtk::Box m_VBox;

  Gtk::ScrolledWindow m_ScrolledWindow;
  TreeView_WithPopup m_TreeView;

  Gtk::ButtonBox m_ButtonBox;
  Gtk::Button m_Button_Quit;
};

#endif //GTKMM_EXAMPLEWINDOW_H
</programlisting>
<para lang="en">File: <filename>treeview_withpopup.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLE_TREEVIEW_WITHPOPUP_H
#define GTKMM_EXAMPLE_TREEVIEW_WITHPOPUP_H

#include &lt;gtkmm.h&gt;

class TreeView_WithPopup : public Gtk::TreeView
{
public:
  TreeView_WithPopup();
  virtual ~TreeView_WithPopup();

protected:
  // Override Signal handler:
  // Alternatively, use signal_button_press_event().connect_notify()
  bool on_button_press_event(GdkEventButton* button_event) override;

  //Signal handler for popup menu items:
  void on_menu_file_popup_generic();


  //Tree model columns:
  class ModelColumns : public Gtk::TreeModel::ColumnRecord
  {
  public:

    ModelColumns()
    { add(m_col_id); add(m_col_name); }

    Gtk::TreeModelColumn&lt;unsigned int&gt; m_col_id;
    Gtk::TreeModelColumn&lt;Glib::ustring&gt; m_col_name;
  };

  ModelColumns m_Columns;

  //The Tree model:
  Glib::RefPtr&lt;Gtk::ListStore&gt; m_refTreeModel;

  Gtk::Menu m_Menu_Popup;
};

#endif //GTKMM_EXAMPLE_TREEVIEW_WITHPOPUP_H
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;gtkmm/application.h&gt;

int main(int argc, char *argv[])
{
  auto app = Gtk::Application::create(argc, argv, "org.gtkmm.example");

  ExampleWindow window;

  //Shows the window and returns when it is closed.
  return app-&gt;run(window);
}
</programlisting>
<para lang="en">File: <filename>treeview_withpopup.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "treeview_withpopup.h"
#include &lt;iostream&gt;

TreeView_WithPopup::TreeView_WithPopup()
{
  //Create the Tree model:
  m_refTreeModel = Gtk::ListStore::create(m_Columns);
  set_model(m_refTreeModel);

  //Fill the TreeView's model
  Gtk::TreeModel::Row row = *(m_refTreeModel-&gt;append());
  row[m_Columns.m_col_id] = 1;
  row[m_Columns.m_col_name] = "right-click on this";

  row = *(m_refTreeModel-&gt;append());
  row[m_Columns.m_col_id] = 2;
  row[m_Columns.m_col_name] = "or this";

  row = *(m_refTreeModel-&gt;append());
  row[m_Columns.m_col_id] = 3;
  row[m_Columns.m_col_name] = "or this, for a popup context menu";

  //Add the TreeView's view columns:
  append_column("ID", m_Columns.m_col_id);
  append_column("Name", m_Columns.m_col_name);

  //Fill popup menu:
  auto item = Gtk::manage(new Gtk::MenuItem("_Edit", true));
  item-&gt;signal_activate().connect(
    sigc::mem_fun(*this, &amp;TreeView_WithPopup::on_menu_file_popup_generic) );
  m_Menu_Popup.append(*item);

  item = Gtk::manage(new Gtk::MenuItem("_Process", true));
  item-&gt;signal_activate().connect(
    sigc::mem_fun(*this, &amp;TreeView_WithPopup::on_menu_file_popup_generic) );
  m_Menu_Popup.append(*item);

  item = Gtk::manage(new Gtk::MenuItem("_Remove", true));
  item-&gt;signal_activate().connect(
    sigc::mem_fun(*this, &amp;TreeView_WithPopup::on_menu_file_popup_generic) );
  m_Menu_Popup.append(*item);

  m_Menu_Popup.accelerate(*this);
  m_Menu_Popup.show_all(); //Show all menu items when the menu pops up
}

TreeView_WithPopup::~TreeView_WithPopup()
{
}

bool TreeView_WithPopup::on_button_press_event(GdkEventButton* button_event)
{
  bool return_value = false;

  //Call base class, to allow normal handling,
  //such as allowing the row to be selected by the right-click:
  return_value = TreeView::on_button_press_event(button_event);

  //Then do our custom stuff:
  if( (button_event-&gt;type == GDK_BUTTON_PRESS) &amp;&amp; (button_event-&gt;button == 3) )
  {
    m_Menu_Popup.popup_at_pointer((GdkEvent*)button_event);

    // Menu::popup_at_pointer() is new in gtkmm 3.22.
    // If you have an older revision, try this:
    //m_Menu_Popup.popup(button_event-&gt;button, button_event-&gt;time);
  }

  return return_value;
}

void TreeView_WithPopup::on_menu_file_popup_generic()
{
  std::cout &lt;&lt; "A popup menu item was selected." &lt;&lt; std::endl;

  auto refSelection = get_selection();
  if(refSelection)
  {
    Gtk::TreeModel::iterator iter = refSelection-&gt;get_selected();
    if(iter)
    {
      int id = (*iter)[m_Columns.m_col_id];
      std::cout &lt;&lt; "  Selected ID=" &lt;&lt; id &lt;&lt; std::endl;
    }
  }
}
</programlisting>
<para lang="en">File: <filename>examplewindow.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include &lt;iostream&gt;
#include "examplewindow.h"

ExampleWindow::ExampleWindow()
: m_VBox(Gtk::ORIENTATION_VERTICAL),
  m_Button_Quit("Quit")
{
  set_title("Gtk::TreeView (ListStore) example");
  set_border_width(5);
  set_default_size(400, 200);

  add(m_VBox);

  //Add the TreeView, inside a ScrolledWindow, with the button underneath:
  m_ScrolledWindow.add(m_TreeView);

  //Only show the scrollbars when they are necessary:
  m_ScrolledWindow.set_policy(Gtk::POLICY_AUTOMATIC, Gtk::POLICY_AUTOMATIC);

  m_VBox.pack_start(m_ScrolledWindow);
  m_VBox.pack_start(m_ButtonBox, Gtk::PACK_SHRINK);

  m_ButtonBox.pack_start(m_Button_Quit, Gtk::PACK_SHRINK);
  m_ButtonBox.set_border_width(5);
  m_ButtonBox.set_layout(Gtk::BUTTONBOX_END);
  m_Button_Quit.signal_clicked().connect( sigc::mem_fun(*this,
              &amp;ExampleWindow::on_button_quit) );

  show_all_children();
}

ExampleWindow::~ExampleWindow()
{
}

void ExampleWindow::on_button_quit()
{
  hide();
}

</programlisting>
<!-- end inserted example code -->

</sect2>


</sect1>

</chapter>


<chapter id="chapter-combobox">
<title>Boîtes combinées</title>

<para lang="en">The <classname>ComboBox</classname> widget offers a list (or tree) of choices in a dropdown menu. If appropriate, it can show extra information about each item, such as text, a picture, a checkbox, or a progress bar. The <classname>ComboBox</classname> widget usually restricts the user to the available choices, but it can optionally have an <classname>Entry</classname>, allowing the user to enter arbitrary text if none of the available choices are suitable.
</para>

<para>La liste est donnée via un objet <classname>TreeModel</classname> et les colonnes provenant de ce modèle sont insérées dans la vue de la boîte combinée avec la fonction membre <methodname>ComboBox::pack_start()</methodname>. Cela procure beaucoup de souplesse et de sécurité sur les types de données à la compilation ; mais la classe <classname>ComboBoxText</classname> dispose d'un paramétrage texte simple pour les cas où cette souplesse n'est pas recherchée.</para>

<para lang="en"><ulink url="http://developer.gnome.org/gtkmm/3.22/classGtk_1_1ComboBox.html">Reference</ulink></para>

<sect1 id="sec-combobox-model">
<title>Le modèle</title>
<para lang="en">The model for a ComboBox can be defined and filled exactly as for a <classname>TreeView</classname>. For instance, you might derive a ComboBox class with one integer and one text column, like so:
</para>
<programlisting>ModelColumns()
{ add(m_col_id); add(m_col_name); }

  Gtk::TreeModelColumn&lt;int&gt; m_col_id;
  Gtk::TreeModelColumn&lt;Glib::ustring&gt; m_col_name;
};

ModelColumns m_columns;</programlisting>

<para lang="en">After appending rows to this model, you should provide the model to the <classname>ComboBox</classname> with the <methodname>set_model()</methodname> method. Then use the <methodname>pack_start()</methodname> or <methodname>pack_end()</methodname> methods to specify what columns will be displayed in the ComboBox. As with the TreeView you may either use the default cell renderer by passing the <classname>TreeModelColumn</classname> to the pack methods, or you may instantiate a specific <classname>CellRenderer</classname> and specify a particular mapping with either <methodname>add_attribute()</methodname> or <methodname>set_cell_data_func()</methodname>. Note that these methods are in the <classname>CellLayout</classname> base class.</para>
</sect1>

<sect1 id="sec-combobox-get">
<title>L'élément choisi</title>
<para lang="en">To discover what item, if any, the user has chosen from the ComboBox, call <methodname>ComboBox::get_active()</methodname>. This returns a <classname>TreeModel::iterator</classname> that you can dereference to a <classname>Row</classname> in order to read the values in your columns. For instance, you might read an integer ID value from the model, even though you have chosen only to show the human-readable description in the ComboBox. For instance:
</para>
<programlisting>Gtk::TreeModel::iterator iter = m_Combo.get_active();
if(iter)
{
  Gtk::TreeModel::Row row = *iter;

  // Obtenir les données de la ligne choisie grâce à notre 
  // connaissance du modèle d'arborescence :
  int id = row[m_Columns.m_col_id];
  set_something_id_chosen(id); // Votre fonction.
}
else
  set_nothing_chosen(); // Votre fonction.</programlisting>
</sect1>

<sect1 id="sec-combobox-changes">
<title>Réponse à une modification</title>
<para lang="en">
You might need to react to every change of selection in the ComboBox, for instance to update other widgets. To do so, you should handle the <literal>changed</literal> signal. For instance:
</para>
<programlisting>m_combo.signal_changed().connect( sigc::mem_fun(*this,
      &amp;ExampleWindow::on_combo_changed) );</programlisting>
</sect1>

<sect1 id="combobox-example-full"><title>Exemple complet</title>

<figure id="figure-combobox-complex">
  <title>ComboBox</title>
  <screenshot>
    <graphic format="PNG" fileref="figures/combobox_complex.png"/>
  </screenshot>
</figure>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/combobox/complex?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>examplewindow.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLEWINDOW_H
#define GTKMM_EXAMPLEWINDOW_H

#include &lt;gtkmm/window.h&gt;
#include &lt;gtkmm/comboboxtext.h&gt;
#include &lt;gtkmm/liststore.h&gt;

class ExampleWindow : public Gtk::Window
{
public:
  ExampleWindow();
  virtual ~ExampleWindow();

protected:
  void on_cell_data_extra(const Gtk::TreeModel::const_iterator&amp; iter);

  //Signal handlers:
  void on_combo_changed();


  //Tree model columns:
  class ModelColumns : public Gtk::TreeModel::ColumnRecord
  {
  public:

    ModelColumns()
    { add(m_col_id); add(m_col_name); add(m_col_extra);}

    Gtk::TreeModelColumn&lt;int&gt; m_col_id;
    Gtk::TreeModelColumn&lt;Glib::ustring&gt; m_col_name;
    Gtk::TreeModelColumn&lt;Glib::ustring&gt; m_col_extra;
  };

  ModelColumns m_Columns;

  //Child widgets:
  Gtk::ComboBox m_Combo;
  Gtk::CellRendererText m_cell;
  Glib::RefPtr&lt;Gtk::ListStore&gt; m_refTreeModel;
};

#endif //GTKMM_EXAMPLEWINDOW_H
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;gtkmm/application.h&gt;

int main(int argc, char *argv[])
{
  auto app = Gtk::Application::create(argc, argv, "org.gtkmm.example");

  ExampleWindow window;

  //Shows the window and returns when it is closed.
  return app-&gt;run(window);
}
</programlisting>
<para lang="en">File: <filename>examplewindow.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;iostream&gt;

ExampleWindow::ExampleWindow()
{
  set_title("ComboBox example");

  //Create the Tree model:
  //m_refTreeModel = Gtk::TreeStore::create(m_Columns);
  m_refTreeModel = Gtk::ListStore::create(m_Columns);
  m_Combo.set_model(m_refTreeModel);

  //Fill the ComboBox's Tree Model:
  Gtk::TreeModel::Row row = *(m_refTreeModel-&gt;append());
  row[m_Columns.m_col_id] = 1;
  row[m_Columns.m_col_name] = "Billy Bob";
  row[m_Columns.m_col_extra] = "something";
  m_Combo.set_active(row);
  /*
  Gtk::TreeModel::Row childrow = *(m_refTreeModel-&gt;append(row.children()));
  childrow[m_Columns.m_col_id] = 11;
  childrow[m_Columns.m_col_name] = "Billy Bob Junior";

  childrow = *(m_refTreeModel-&gt;append(row.children()));
  childrow[m_Columns.m_col_id] = 12;
  childrow[m_Columns.m_col_name] = "Sue Bob";
  */

  row = *(m_refTreeModel-&gt;append());
  row[m_Columns.m_col_id] = 2;
  row[m_Columns.m_col_name] = "Joey Jojo";
  row[m_Columns.m_col_extra] = "yadda";


  row = *(m_refTreeModel-&gt;append());
  row[m_Columns.m_col_id] = 3;
  row[m_Columns.m_col_name] = "Rob McRoberts";
  row[m_Columns.m_col_extra] = "";

  /*
  childrow = *(m_refTreeModel-&gt;append(row.children()));
  childrow[m_Columns.m_col_id] = 31;
  childrow[m_Columns.m_col_name] = "Xavier McRoberts";
  */

  //Add the model columns to the Combo (which is a kind of view),
  //rendering them in the default way:
  m_Combo.pack_start(m_Columns.m_col_id);
  m_Combo.pack_start(m_Columns.m_col_name);

  //An example of adding a cell renderer manually,
  //instead of using pack_start(model_column)
  //so we have more control:
  m_Combo.set_cell_data_func(m_cell,
    sigc::mem_fun(*this, &amp;ExampleWindow::on_cell_data_extra));
  m_Combo.pack_start(m_cell);

  //Add the ComboBox to the window.
  add(m_Combo);

  //Connect signal handler:
  m_Combo.signal_changed().connect( sigc::mem_fun(*this, &amp;ExampleWindow::on_combo_changed) );

  show_all_children();
}

ExampleWindow::~ExampleWindow()
{
}

void ExampleWindow::on_cell_data_extra(const Gtk::TreeModel::const_iterator&amp; iter)
{
  auto row = *iter;
  const Glib::ustring extra = row[m_Columns.m_col_extra];

  //Some arbitrary logic just to show that this is where you can do such things:

  //Transform the value, deciding how to represent it as text:
  if(extra.empty())
    m_cell.property_text() = "(none)";
  else
    m_cell.property_text() = "-" + extra + "-";

  //Change other cell renderer properties too:
  m_cell.property_foreground() = (extra == "yadda" ? "red" : "green");
}

void ExampleWindow::on_combo_changed()
{
  Gtk::TreeModel::iterator iter = m_Combo.get_active();
  if(iter)
  {
    Gtk::TreeModel::Row row = *iter;
    if(row)
    {
      //Get the data for the selected row, using our knowledge of the tree
      //model:
      int id = row[m_Columns.m_col_id];
      Glib::ustring name = row[m_Columns.m_col_name];

      std::cout &lt;&lt; " ID=" &lt;&lt; id &lt;&lt; ", name=" &lt;&lt; name &lt;&lt; std::endl;
    }
  }
  else
    std::cout &lt;&lt; "invalid iter" &lt;&lt; std::endl;
}

</programlisting>
<!-- end inserted example code -->

</sect1>

<sect1 id="combobox-example-simple"><title>Exemple texte simple</title>

<figure id="figure-combobox-text">
  <title lang="en">ComboBoxText</title>
  <screenshot>
    <graphic format="PNG" fileref="figures/combobox_text.png"/>
  </screenshot>
</figure>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/combobox/text?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>examplewindow.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLEWINDOW_H
#define GTKMM_EXAMPLEWINDOW_H

#include &lt;gtkmm/window.h&gt;
#include &lt;gtkmm/comboboxtext.h&gt;

class ExampleWindow : public Gtk::Window
{
public:
  ExampleWindow();
  virtual ~ExampleWindow();

protected:
  //Signal handlers:
  void on_combo_changed();

  //Child widgets:
  Gtk::ComboBoxText m_Combo;
};

#endif //GTKMM_EXAMPLEWINDOW_H
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;gtkmm/application.h&gt;

int main(int argc, char *argv[])
{
  auto app = Gtk::Application::create(argc, argv, "org.gtkmm.example");

  ExampleWindow window;

  //Shows the window and returns when it is closed.
  return app-&gt;run(window);
}
</programlisting>
<para lang="en">File: <filename>examplewindow.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;iostream&gt;

ExampleWindow::ExampleWindow()
{
  set_title("ComboBoxText example");

  //Fill the combo:
  m_Combo.append("something");
  m_Combo.append("something else");
  m_Combo.append("something or other");
  m_Combo.set_active(1);

  add(m_Combo);

  //Connect signal handler:
  m_Combo.signal_changed().connect(sigc::mem_fun(*this,
              &amp;ExampleWindow::on_combo_changed) );

  show_all_children();
}

ExampleWindow::~ExampleWindow()
{
}

void ExampleWindow::on_combo_changed()
{
  Glib::ustring text = m_Combo.get_active_text();
  if(!(text.empty()))
    std::cout &lt;&lt; "Combo changed: " &lt;&lt; text &lt;&lt; std::endl;
}

</programlisting>
<!-- end inserted example code -->

</sect1>

<sect1 id="sec-comboboxentry">
<title>Boîte combinée avec saisie</title>

<para lang="en">A <classname>ComboBox</classname> may contain an <classname>Entry</classname> widget for entering of arbitrary text, by specifying <literal>true</literal> for the constructor's <literal>has_entry</literal> parameter.</para>

<sect2 id="sec-comboboxentry-text-column">
<title>La colonne texte</title>
<para lang="en">So that the <classname>Entry</classname> can interact with the drop-down list of choices, you must specify which of your model columns is the text column, with <methodname>set_entry_text_column()</methodname>. For instance:
<programlisting lang="en">m_combo.set_entry_text_column(m_columns.m_col_name);</programlisting>
</para>
<para>Si vous faites une sélection dans le menu déroulant, la valeur de cette colonne sera placée dans l'élément graphique <classname>Entry</classname>.</para>
</sect2>

<sect2 id="sec-comboboxentry-model">
<title>La saisie</title>
<para lang="en">Because the user may enter arbitrary text, an active model row isn't enough to tell us what text the user has entered. Therefore, you should retrieve the <classname>Entry</classname> widget with the <methodname>ComboBox::get_entry()</methodname> method and call <methodname>get_text()</methodname> on that.
</para>
</sect2>

<sect2 id="sec-comboboxentry-changes">
<title>Réponse à une modification</title>
<para lang="en">
When the user enters arbitrary text, it may not be enough to connect to the
<literal>changed</literal> signal, which is emitted for every typed character.
It is not emitted when the user presses the Enter key. Pressing the Enter key or
moving the keyboard focus to another widget may signal that the user has finished
entering text. To be notified of these events, connect to the
<classname>Entry</classname>'s <literal>activate</literal> and
<literal>focus_out_event</literal> signals, like so
<programlisting lang="en">Gtk::Entry* entry = m_Combo.get_entry();
if (entry)
{
  // The Entry shall receive focus-out events.
  entry-&gt;add_events(Gdk::FOCUS_CHANGE_MASK);

  // Alternatively you can connect to m_Combo.signal_changed().
  entry-&gt;signal_changed().connect(sigc::mem_fun(*this,
    &amp;ExampleWindow::on_entry_changed) );

  entry-&gt;signal_activate().connect(sigc::mem_fun(*this,
    &amp;ExampleWindow::on_entry_activate) );

  entry-&gt;signal_focus_out_event().connect(sigc::mem_fun(*this,
    &amp;ExampleWindow::on_entry_focus_out_event) );
}</programlisting>
The <literal>changed</literal> signals of <classname>ComboBox</classname> and
<classname>Entry</classname> are both emitted for every change. It doesn't matter
which one you connect to. But only <classname>Entry</classname>'s
<literal>focus_out_event</literal> signal is useful here.
</para>
<para lang="en">
X events are described in more detail in the
<link linkend="sec-xeventsignals">X Event signals</link> section in the appendix.
</para>
</sect2>

<sect2 id="comboboxentry-example-full"><title>Exemple complet</title>

<figure id="figure-comboboxentry-complex">
  <title lang="en">ComboBox with Entry</title>
  <screenshot>
    <graphic format="PNG" fileref="figures/comboboxentry_complex.png"/>
  </screenshot>
</figure>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/combobox/entry_complex?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>examplewindow.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLEWINDOW_H
#define GTKMM_EXAMPLEWINDOW_H

#include &lt;gtkmm/window.h&gt;
#include &lt;gtkmm/combobox.h&gt;
#include &lt;gtkmm/liststore.h&gt;

class ExampleWindow : public Gtk::Window
{
public:
  ExampleWindow();
  virtual ~ExampleWindow();

protected:
  //Signal handlers:
  void on_entry_changed();
  void on_entry_activate();
  bool on_entry_focus_out_event(GdkEventFocus* event);

  //Signal connection:
  sigc::connection m_ConnectionFocusOut;

  //Tree model columns:
  class ModelColumns : public Gtk::TreeModel::ColumnRecord
  {
  public:

    ModelColumns()
    { add(m_col_id); add(m_col_name); }

    Gtk::TreeModelColumn&lt;Glib::ustring&gt; m_col_id; //The data to choose - this must be text.
    Gtk::TreeModelColumn&lt;Glib::ustring&gt; m_col_name;
  };

  ModelColumns m_Columns;

  //Child widgets:
  Gtk::ComboBox m_Combo;
  Glib::RefPtr&lt;Gtk::ListStore&gt; m_refTreeModel;
};

#endif //GTKMM_EXAMPLEWINDOW_H
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;gtkmm/application.h&gt;

int main(int argc, char *argv[])
{
  auto app = Gtk::Application::create(argc, argv, "org.gtkmm.example");

  ExampleWindow window;

  //Shows the window and returns when it is closed.
  return app-&gt;run(window);
}
</programlisting>
<para lang="en">File: <filename>examplewindow.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;iostream&gt;

ExampleWindow::ExampleWindow()
: m_Combo(true /* has_entry */)
{
  set_title("ComboBox example");

  //Create the Tree model:
  //m_refTreeModel = Gtk::TreeStore::create(m_Columns);
  m_refTreeModel = Gtk::ListStore::create(m_Columns);
  m_Combo.set_model(m_refTreeModel);

  //Fill the ComboBox's Tree Model:
  Gtk::TreeModel::Row row = *(m_refTreeModel-&gt;append());
  row[m_Columns.m_col_id] = "1";
  row[m_Columns.m_col_name] = "Billy Bob";
  /*
  Gtk::TreeModel::Row childrow = *(m_refTreeModel-&gt;append(row.children()));
  childrow[m_Columns.m_col_id] = 11;
  childrow[m_Columns.m_col_name] = "Billy Bob Junior";

  childrow = *(m_refTreeModel-&gt;append(row.children()));
  childrow[m_Columns.m_col_id] = 12;
  childrow[m_Columns.m_col_name] = "Sue Bob";
  */

  row = *(m_refTreeModel-&gt;append());
  row[m_Columns.m_col_id] = "2";
  row[m_Columns.m_col_name] = "Joey Jojo";

  row = *(m_refTreeModel-&gt;append());
  row[m_Columns.m_col_id] = "3";
  row[m_Columns.m_col_name] = "Rob McRoberts";

  /*
  childrow = *(m_refTreeModel-&gt;append(row.children()));
  childrow[m_Columns.m_col_id] = 31;
  childrow[m_Columns.m_col_name] = "Xavier McRoberts";
  */

  //Add the model columns to the Combo (which is a kind of view),
  //rendering them in the default way:
  //This is automatically rendered when we use set_entry_text_column().
  //m_Combo.pack_start(m_Columns.m_col_id);
  m_Combo.pack_start(m_Columns.m_col_name);

  m_Combo.set_entry_text_column(m_Columns.m_col_id);
  m_Combo.set_active(1);

  //Add the ComboBox to the window.
  add(m_Combo);

  //Connect signal handlers:
  auto entry = m_Combo.get_entry();
  if (entry)
  {
    // The Entry shall receive focus-out events.
    entry-&gt;add_events(Gdk::FOCUS_CHANGE_MASK);
    // Alternatively you can connect to m_Combo.signal_changed().
    entry-&gt;signal_changed().connect(sigc::mem_fun(*this,
      &amp;ExampleWindow::on_entry_changed) );
    entry-&gt;signal_activate().connect(sigc::mem_fun(*this,
      &amp;ExampleWindow::on_entry_activate) );
    m_ConnectionFocusOut = entry-&gt;signal_focus_out_event().
      connect(sigc::mem_fun(*this, &amp;ExampleWindow::on_entry_focus_out_event) );
  }
  else
    std::cout &lt;&lt; "No Entry ???" &lt;&lt; std::endl;

  show_all_children();
}

ExampleWindow::~ExampleWindow()
{
  // The focus_out signal may be emitted while m_Combo is being destructed.
  // The signal handler can generate critical messages, if it's called when
  // m_Combo has been partly destructed.
  m_ConnectionFocusOut.disconnect();
}

void ExampleWindow::on_entry_changed()
{
  auto entry = m_Combo.get_entry();
  if (entry)
  {
    std::cout &lt;&lt; "on_entry_changed(): Row=" &lt;&lt; m_Combo.get_active_row_number()
      &lt;&lt; ", ID=" &lt;&lt; entry-&gt;get_text() &lt;&lt; std::endl;
  }
}

void ExampleWindow::on_entry_activate()
{
  auto entry = m_Combo.get_entry();
  if (entry)
  {
    std::cout &lt;&lt; "on_entry_activate(): Row=" &lt;&lt; m_Combo.get_active_row_number()
      &lt;&lt; ", ID=" &lt;&lt; entry-&gt;get_text() &lt;&lt; std::endl;
  }
}

bool ExampleWindow::on_entry_focus_out_event(GdkEventFocus* /* event */)
{
  auto entry = m_Combo.get_entry();
  if (entry)
  {
    std::cout &lt;&lt; "on_entry_focus_out_event(): Row=" &lt;&lt; m_Combo.get_active_row_number()
      &lt;&lt; ", ID=" &lt;&lt; entry-&gt;get_text() &lt;&lt; std::endl;
    return true;
  }
  return false;
}
</programlisting>
<!-- end inserted example code -->

</sect2>

<sect2 id="comboboxentry-example-simple"><title>Exemple texte simple</title>

<figure id="figure-comboboxentry-text">
  <title lang="en">ComboBoxText with Entry</title>
  <screenshot>
    <graphic format="PNG" fileref="figures/comboboxentry_text.png"/>
  </screenshot>
</figure>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/combobox/entry_text?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>examplewindow.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLEWINDOW_H
#define GTKMM_EXAMPLEWINDOW_H

#include &lt;gtkmm/window.h&gt;
#include &lt;gtkmm/comboboxtext.h&gt;

class ExampleWindow : public Gtk::Window
{
public:
  ExampleWindow();
  virtual ~ExampleWindow();

protected:
  //Signal handlers:
  void on_combo_changed();
  void on_entry_activate();
  bool on_entry_focus_out_event(GdkEventFocus* event);

  //Signal connection:
  sigc::connection m_ConnectionFocusOut;

  //Child widgets:
  Gtk::ComboBoxText m_Combo;
};

#endif //GTKMM_EXAMPLEWINDOW_H
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;gtkmm/application.h&gt;

int main(int argc, char *argv[])
{
  auto app = Gtk::Application::create(argc, argv, "org.gtkmm.example");

  ExampleWindow window;

  //Shows the window and returns when it is closed.
  return app-&gt;run(window);
}
</programlisting>
<para lang="en">File: <filename>examplewindow.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;iostream&gt;

ExampleWindow::ExampleWindow()
: m_Combo(true /* has_entry */)
{
  set_title("ComboBoxText example");

  //Fill the combo:
  m_Combo.append("something");
  m_Combo.append("something else");
  m_Combo.append("something or other");
  m_Combo.set_active(0);

  add(m_Combo);

  //Connect signal handlers:
  auto entry = m_Combo.get_entry();
  // Alternatively you can connect to entry-&gt;signal_changed().
  m_Combo.signal_changed().connect(sigc::mem_fun(*this,
    &amp;ExampleWindow::on_combo_changed) );
  if (entry)
  {
    // The Entry shall receive focus-out events.
    entry-&gt;add_events(Gdk::FOCUS_CHANGE_MASK);
    entry-&gt;signal_activate().connect(sigc::mem_fun(*this,
      &amp;ExampleWindow::on_entry_activate) );
    m_ConnectionFocusOut = entry-&gt;signal_focus_out_event().
      connect(sigc::mem_fun(*this, &amp;ExampleWindow::on_entry_focus_out_event) );
  }
  else
    std::cout &lt;&lt; "No Entry ???" &lt;&lt; std::endl;

  m_Combo.property_has_frame() = false;
  show_all_children();
}

ExampleWindow::~ExampleWindow()
{
  // The focus_out signal may be emitted while m_Combo is being destructed.
  // The signal handler can generate critical messages, if it's called when
  // m_Combo has been partly destructed.
  m_ConnectionFocusOut.disconnect();
}

void ExampleWindow::on_combo_changed()
{
  std::cout &lt;&lt; "on_combo_changed(): Row=" &lt;&lt; m_Combo.get_active_row_number()
    &lt;&lt; ", Text=" &lt;&lt; m_Combo.get_active_text() &lt;&lt; std::endl;
}

void ExampleWindow::on_entry_activate()
{
  std::cout &lt;&lt; "on_entry_activate(): Row=" &lt;&lt; m_Combo.get_active_row_number()
    &lt;&lt; ", Text=" &lt;&lt; m_Combo.get_active_text() &lt;&lt; std::endl;
}

bool ExampleWindow::on_entry_focus_out_event(GdkEventFocus* /* event */)
{
  std::cout &lt;&lt; "on_entry_focus_out_event(): Row=" &lt;&lt; m_Combo.get_active_row_number()
    &lt;&lt; ", Text=" &lt;&lt; m_Combo.get_active_text() &lt;&lt; std::endl;
  return true;
}
</programlisting>
<!-- end inserted example code -->

</sect2>




</sect1>

</chapter>


<chapter id="chapter-textview">
<title>Élément graphique TextView</title>
<para>L'élément graphique <classname>TextView</classname> s'utilise pour afficher et modifier de grosses quantités de texte formatté. Comme l'objet <classname>TreeView</classname>, il y a une correspondance vue/modèle. Dans le cas présent, le modèle est l'objet <classname>TextBuffer</classname>.</para>

<sect1 id="sec-textview-buffer">
<title>Le tampon</title>
<para><classname>Gtk::TextBuffer</classname> est un modèle contenant les données pour <classname>Gtk::TextView</classname>, tout comme <classname>Gtk::TreeModel</classname> utilisé par <classname>Gtk::TreeView</classname>. Cela permet à deux <classname>Gtk::TextView</classname> ou plus de partager le même <classname>TextBuffer</classname> tout en étant affichés de façon légèrement différente. Ou bien encore, vous pouvez disposer de plusieurs <classname>Gtk::TextBuffer</classname> et choisir d'afficher dans le même élément graphique <classname>Gtk::TextView</classname> le contenu de l'un ou l'autre d'entre eux selon les circonstances.</para>
<para>L'objet <classname>TextView</classname> crée par défaut son propre <classname>TextBuffer</classname>. Vous y accédez avec la fonction membre <methodname>get_buffer()</methodname>.</para>

<para lang="en"><ulink url="http://developer.gnome.org/gtkmm/3.22/classGtk_1_1TextBuffer.html">Reference</ulink></para>

<sect2 id="textview-iterators">
<title>Itérateurs</title>
<para>
</para>
</sect2>

<sect2 id="textview-formatting">
<title>Balisages et formats</title>

<sect3 id="textview-formatting-tags">
<title>Balisages</title>
<para>Pour indiquer que du texte dans le tampon doit bénéficier de tel ou tel format, vous devez définir une balise précisant cette information de format, puis appliquer ce balisage à une zone de texte. Ainsi, pour définir le balisage et ses propriétés :</para>
<programlisting>Glib::RefPtr&lt;Gtk::TextBuffer::Tag&gt; refTagMatch =
    Gtk::TextBuffer::Tag::create();
refTagMatch-&gt;property_background() = "orange";</programlisting>
<para>Vous pouvez définir un nom pour l'objet <classname>Tag</classname> quand vous appelez la fonction membre <methodname>create()</methodname>, mais ce n'est pas obligatoire.</para>

<para>La classe <classname>Tag</classname> dispose de nombreuses autres propriétés.</para>

<para lang="en"><ulink url="http://developer.gnome.org/gtkmm/3.22/classGtk_1_1TextTag.html">Reference</ulink></para>

</sect3>

<sect3 id="textview-formatting-tagtable">
<title>Tableau des balises</title>

<para>Chaque <classname>Gtk::TextBuffer</classname> utilise un objet <classname>Gtk::TextBuffer::TagTable</classname> contenant les balises pour ce tampon. Deux objets <classname>TextBuffer</classname> ou plus peuvent partager le même objet <classname>TagTable</classname>. Quand vous créez un objet <classname>Tag</classname> vous devez l'incorporer dans l'objet <classname>TagTable</classname>. Par exemple :</para>
<programlisting>Glib::RefPtr&lt;Gtk::TextBuffer::TagTable&gt; refTagTable =
    Gtk::TextBuffer::TagTable::create();
refTagTable-&gt;add(refTagMatch);
// Avec un peu de chance une future version de <application>gtkmm</application> 
// disposera d'une fonction membre set_tag_table(),
// à utiliser après la création du tampon.
Glib::RefPtr&lt;Gtk::TextBuffer&gt; refBuffer =
    Gtk::TextBuffer::create(refTagTable);</programlisting>

<para>Vous pouvez aussi utiliser <methodname>get_tag_table()</methodname> pour obtenir, et peut-être modifier, l'objet <classname>TagTable</classname> par défaut du <classname>TextBuffer</classname> au lieu d'en créer un explicitement.</para>

<para lang="en"><ulink url="http://developer.gnome.org/gtkmm/3.22/classGtk_1_1TextTagTable.html">Reference</ulink></para>

</sect3>

<sect3 id="textview-formatting-applying-tags">
<title>Application des balises</title>
<para>Si vous avez créé un <classname>Tag</classname> et l'avez ajouté à l'objet <classname>TagTable</classname>, vous pouvez appliquer cette balise sur une partie du texte du <classname>TextBuffer</classname> et faire ainsi en sorte que ce texte soit affiché avec ce format. Vous définissez le début et la fin de la plage de texte en définissant des marqueurs du type  <classname>Gtk::TextBuffer::iterator</classname>. Par exemple :</para>
<programlisting>refBuffer-&gt;apply_tag(refTagMatch, iterRangeStart, iterRangeStop);</programlisting>
<para lang="en">
Or you could specify the tag when first inserting the text:
<programlisting lang="en">refBuffer-&gt;insert_with_tag(iter, "Some text", refTagMatch);</programlisting>
</para>

<para>Vous pouvez appliquer plus d'un objet <classname>Tag</classname> au même texte en utilisant plusieurs fois la fonction membre <methodname>apply_tag()</methodname> ou en utilisant <methodname>insert_with_tags()</methodname>. L'objet <classname>Tag</classname> peut définir des valeurs différentes pour les mêmes propriétés : dans ce cas là, il faut résoudre les conflits avec la fonction membre <methodname>Tag::set_priority()</methodname>.</para>

</sect3>
</sect2>

<sect2 id="textview-marks">
<title>Marquages</title>
<para>Les itérateurs du <classname>TextBuffer</classname> sont généralement invalidés si le texte est modifié ; mais, vous pouvez utiliser un objet <classname>Gtk::TextBuffer::Mark</classname> pour mémoriser une position dans ces cas-là. Par exemple :</para>
<programlisting>Glib::RefPtr&lt;Gtk::TextBuffer::Mark&gt; refMark =
    refBuffer-&gt;create_mark(iter);</programlisting>

<para>Puis vous utiliserez ultérieurement la fonction membre <methodname>get_iter()</methodname> pour créer un itérateur pour la nouvelle position de l'objet <classname>Mark</classname>.</para>

<para lang="en">
There are two built-in <classname>Mark</classname>s - <literal>insert</literal>
and <literal>selection_bound</literal>, which you can access with
<classname>TextBuffer</classname>'s <methodname>get_insert()</methodname> and
<methodname>get_selection_bound()</methodname> methods.
</para>

<para lang="en"><ulink url="http://developer.gnome.org/gtkmm/3.22/classGtk_1_1TextMark.html">Reference</ulink></para>

</sect2>

<sect2 id="textview-view">
<title>La vue</title>
<para lang="en">
As mentioned above, each <classname>TextView</classname> has a
<classname>TextBuffer</classname>, and one or more
<classname>TextView</classname>s can share the same
<classname>TextBuffer</classname>.
</para>

<para>Comme pour un <classname>TreeView</classname>, vous pouvez placer l'objet <classname>TextView</classname> dans un objet <classname>ScrolledWindow</classname> pour permettre à l'utilisateur d'explorer la totalité du texte à l'aide de barres de défilement.</para>

<para lang="en"><ulink url="http://developer.gnome.org/gtkmm/3.22/classGtk_1_1TextView.html">Reference</ulink></para>

<sect3 id="textview-default-formatting">
<title>Format par défaut</title>
<para><classname>TextView</classname> dispose de diverses fonctions membres vous permettant de changer la présentation du contenu du tampon dans cette vue. Certaines peuvent être surdéfinies par les objets <classname>Gtk::TextTag</classname> dans le tampon, si elles définissent les mêmes choses. Par exemple, <methodname>set_left_margin()</methodname>, <methodname>set_right_margin()</methodname>, <methodname>set_indent()</methodname>, etc.</para>
</sect3>

<sect3 id="textview-scrolling">
<title>Défilement</title>
<para><classname>Gtk::TextView</classname> dispose de diverses fonctions membres <methodname>scroll_to_*()</methodname>. Elles vous permettent de vous assurer qu'une zone donnée du texte du tampon est visible. Ainsi, la fonctionnalité Rechercher de votre application pourra utiliser la fonction membre <methodname>Gtk::TextView::scroll_to_iter()</methodname> pour afficher le texte trouvé.</para>
</sect3>

</sect2>


</sect1>

<sect1 id="sec-widgets-and-childanchors">
<title>Éléments graphiques et ancres pour enfant</title>
<para>Vous pouvez incorporer des éléments graphiques, comme des <classname>Gtk::Button</classname>, dans le texte. Chaque élément graphique de ce type a besoin d'un objet <classname>ChildAnchor</classname>. Les ancrages des (objets) enfants sont associés à des <classname>iterators</classname>. Ainsi, pour créer un ancrage pour un objet enfant à une position donnée, utilisez <methodname>Gtk::TextBuffer::create_child_anchor()</methodname> :</para>
<programlisting>Glib::RefPtr&lt;Gtk::TextChildAnchor&gt; refAnchor =
    refBuffer-&gt;create_child_anchor(iter);</programlisting>

<para>Puis, pour ajouter l'élément graphique à la position indiquée, servez-vous de <methodname>Gtk::TextView::add_child_at_anchor()</methodname> :</para>
<programlisting>m_TextView.add_child_at_anchor(m_Button, refAnchor);</programlisting>

<para lang="en"><ulink url="http://developer.gnome.org/gtkmm/3.22/classGtk_1_1TextChildAnchor.html">Reference</ulink></para>

</sect1>

<sect1 id="sec-textview-examples"><title>Exemples</title>

<sect2 id="textview-example-simple"><title>Un exemple simple</title>

<figure id="figure-textview">
  <title>Élément graphique TextView</title>
  <screenshot>
    <graphic format="PNG" fileref="figures/textview.png"/>
  </screenshot>
</figure>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/textview/?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>examplewindow.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLEWINDOW_H
#define GTKMM_EXAMPLEWINDOW_H

#include &lt;gtkmm.h&gt;

class ExampleWindow : public Gtk::Window
{
public:
  ExampleWindow();
  virtual ~ExampleWindow();

protected:

  void fill_buffers();

  //Signal handlers:
  void on_button_quit();
  void on_button_buffer1();
  void on_button_buffer2();

  //Child widgets:
  Gtk::Box m_VBox;

  Gtk::ScrolledWindow m_ScrolledWindow;
  Gtk::TextView m_TextView;

  Glib::RefPtr&lt;Gtk::TextBuffer&gt; m_refTextBuffer1, m_refTextBuffer2;

  Gtk::ButtonBox m_ButtonBox;
  Gtk::Button m_Button_Quit, m_Button_Buffer1, m_Button_Buffer2;
};

#endif //GTKMM_EXAMPLEWINDOW_H
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;gtkmm/application.h&gt;

int main(int argc, char *argv[])
{
  auto app = Gtk::Application::create(argc, argv, "org.gtkmm.example");

  ExampleWindow window;

  //Shows the window and returns when it is closed.
  return app-&gt;run(window);
}
</programlisting>
<para lang="en">File: <filename>examplewindow.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"

ExampleWindow::ExampleWindow()
: m_VBox(Gtk::ORIENTATION_VERTICAL),
  m_Button_Quit("_Quit", true),
  m_Button_Buffer1("Use buffer 1"),
  m_Button_Buffer2("Use buffer 2")
{
  set_title("Gtk::TextView example");
  set_border_width(5);
  set_default_size(400, 200);

  add(m_VBox);

  //Add the TreeView, inside a ScrolledWindow, with the button underneath:
  m_ScrolledWindow.add(m_TextView);

  //Only show the scrollbars when they are necessary:
  m_ScrolledWindow.set_policy(Gtk::POLICY_AUTOMATIC, Gtk::POLICY_AUTOMATIC);

  m_VBox.pack_start(m_ScrolledWindow);

  //Add buttons:
  m_VBox.pack_start(m_ButtonBox, Gtk::PACK_SHRINK);

  m_ButtonBox.pack_start(m_Button_Buffer1, Gtk::PACK_SHRINK);
  m_ButtonBox.pack_start(m_Button_Buffer2, Gtk::PACK_SHRINK);
  m_ButtonBox.pack_start(m_Button_Quit, Gtk::PACK_SHRINK);
  m_ButtonBox.set_border_width(5);
  m_ButtonBox.set_spacing(5);
  m_ButtonBox.set_layout(Gtk::BUTTONBOX_END);

  //Connect signals:
  m_Button_Quit.signal_clicked().connect(sigc::mem_fun(*this,
              &amp;ExampleWindow::on_button_quit) );
  m_Button_Buffer1.signal_clicked().connect(sigc::mem_fun(*this,
              &amp;ExampleWindow::on_button_buffer1) );
  m_Button_Buffer2.signal_clicked().connect(sigc::mem_fun(*this,
              &amp;ExampleWindow::on_button_buffer2) );

  fill_buffers();
  on_button_buffer1();

  show_all_children();
}

void ExampleWindow::fill_buffers()
{
  m_refTextBuffer1 = Gtk::TextBuffer::create();
  m_refTextBuffer1-&gt;set_text("This is the text from TextBuffer #1.");

  m_refTextBuffer2 = Gtk::TextBuffer::create();
  m_refTextBuffer2-&gt;set_text(
          "This is some alternative text, from TextBuffer #2.");

}

ExampleWindow::~ExampleWindow()
{
}

void ExampleWindow::on_button_quit()
{
  hide();
}

void ExampleWindow::on_button_buffer1()
{
  m_TextView.set_buffer(m_refTextBuffer1);
}

void ExampleWindow::on_button_buffer2()
{
  m_TextView.set_buffer(m_refTextBuffer2);
}

</programlisting>
<!-- end inserted example code -->

</sect2>

</sect1>

</chapter>

<chapter id="chapter-menus-and-toolbars">
<title>Menus et barres d'outils</title>

<para lang="en">
There are specific APIs for menus and toolbars, but you should usually deal
with them together, creating <classname>Gio::SimpleAction</classname>s that
you can refer to in both menus and toolbars. In this way you can handle
activation of the action instead of responding to the menu and toolbar items
separately. And you can enable or disable both the menu and toolbar item via
the action. <classname>Gtk::Builder</classname> can create menus and toolbars.
</para>
<para lang="en">
This involves the use of the <classname>Gio::SimpleActionGroup</classname>,
<classname>Gio::SimpleAction</classname> and <classname>Gtk::Builder</classname>
classes, all of which should be instantiated via their <methodname>create()</methodname>
methods, which return <classname>RefPtr</classname>s.
</para>
<para lang="en">
<classname>Gtk::ActionGroup</classname>, <classname>Gtk::Action</classname> with
its subclasses and <classname>Gtk::UIManager</classname> has been an alternative.
These classes are deprecated from <application>gtkmm</application> version 3.22 and should not be used in
newly-written code.
</para>

<sect1 id="sec-actions">
<title>Actions</title>
<para lang="en">
First create the <classname>Gio::SimpleAction</classname>s and add them to a
<classname>Gio::SimpleActionGroup</classname>, with
<methodname>Gio::ActionMap::add_action()</methodname>.
(<classname>Gio::ActionMap</classname> is a base class of
<classname>Gio::SimpleActionGroup</classname>.) Then add the action group to
your window with <methodname>Gtk::Widget::insert_action_group()</methodname>.
</para>
<para lang="en">
The arguments to <methodname>add_action()</methodname> specify the action's
name, which is used in the menu items and toolbar buttons. You can also specify
a signal handler when calling <methodname>add_action()</methodname>. This signal
handler will be called when the action is activated via either a menu item or
a toolbar button.
</para>

<para>Par exemple :</para>
<programlisting lang="en">
<![CDATA[m_refActionGroup = Gio::SimpleActionGroup::create();

m_refActionGroup->add_action("new", sigc::mem_fun(*this, &ExampleWindow::on_action_file_new));
m_refActionGroup->add_action("open", sigc::mem_fun(*this, &ExampleWindow::on_action_file_open));
m_refActionGroup->add_action("quit", sigc::mem_fun(*this, &ExampleWindow::on_action_file_quit));

insert_action_group("example", m_refActionGroup);]]>
</programlisting>

<para lang="en">
If you use an <classname>Gtk::ApplicationWindow</classname>, you don't have to
create your own action group. <classname>Gio::ActionGroup</classname> and
<classname>Gio::ActionMap</classname> are base classes of
<classname>Gtk::ApplicationWindow</classname>.
</para>

</sect1>


<sect1 id="sec-menubar-and-toolbar">
<title lang="en">Menubar and Toolbar</title>
<para lang="en">
Next you should create a <classname>Gtk::Builder</classname>. At this point is
also a good idea to tell the application to respond to keyboard shortcuts,
by using <methodname>Gtk::Application::set_accel_for_action()</methodname>.
</para>

<para>Par exemple,</para>
<programlisting lang="en">
<![CDATA[Glib::RefPtr<Gtk::Builder> m_refBuilder = Gtk::Builder::create();

app->set_accel_for_action("example.new", "<Primary>n");
app->set_accel_for_action("example.quit", "<Primary>q");
app->set_accel_for_action("example.copy", "<Primary>c");
app->set_accel_for_action("example.paste", "<Primary>v");]]>
</programlisting>
<para lang="en">
If your main window is derived from <classname>ApplicationWindow</classname> and
you instantiate your menubar with <methodname>Gtk::Application::set_menubar()</methodname>,
then you don't have to call <methodname>set_accel_for_action()</methodname>.
See <link linkend="menu-example-main">Application Menu and Main Menu example</link>
for an example.
</para>

<para lang="en">
Then, you can define the actual visible layout of the menus and toolbars, and
add the UI layout to the <classname>Builder</classname>. This "ui
string" uses an XML format, in which you should mention the names of the
actions that you have already created. For instance:
</para>
<programlisting lang="en">
<![CDATA[const char* ui_info =
  "<interface>"
  "  <menu id='menubar'>"
  "    <submenu>"
  "      <attribute name='label' translatable='yes'>_File</attribute>"
  "      <section>"
  "        <item>"
  "          <attribute name='label' translatable='yes'>_New</attribute>"
  "          <attribute name='action'>example.new</attribute>"
  "          <attribute name='accel'>&lt;Primary&gt;n</attribute>"
  "        </item>"
  "      </section>"
  "      <section>"
  "        <item>"
  "          <attribute name='label' translatable='yes'>_Quit</attribute>"
  "          <attribute name='action'>example.quit</attribute>"
  "          <attribute name='accel'>&lt;Primary&gt;q</attribute>"
  "        </item>"
  "      </section>"
  "    </submenu>"
  "    <submenu>"
  "      <attribute name='label' translatable='yes'>_Edit</attribute>"
  "      <item>"
  "        <attribute name='label' translatable='yes'>_Copy</attribute>"
  "        <attribute name='action'>example.copy</attribute>"
  "        <attribute name='accel'>&lt;Primary&gt;c</attribute>"
  "      </item>"
  "      <item>"
  "        <attribute name='label' translatable='yes'>_Paste</attribute>"
  "        <attribute name='action'>example.paste</attribute>"
  "        <attribute name='accel'>&lt;Primary&gt;v</attribute>"
  "      </item>"
  "    </submenu>"
  "  </menu>"
  "</interface>";

m_refBuilder->add_from_string(ui_info);
m_refBuilder->add_from_resource("/toolbar/toolbar.glade");]]>
</programlisting>

<para lang="en">This is where we specify the names of the menu items as they will be seen
by users in the menu. Therefore, this is where you should make strings
translatable, by adding <literal>translatable='yes'</literal>.
</para>
<para lang="en">
To instantiate a <classname>Gtk::MenuBar</classname> and
<classname>Gtk::Toolbar</classname> which you can actually show, you should use
the <methodname>Builder::get_object()</methodname> and
<methodname>Builder::get_widget()</methodname> methods, and then add the widgets
to a container. For instance:
</para>
<programlisting lang="en">
<![CDATA[Glib::RefPtr<Glib::Object> object = m_refBuilder->get_object("menubar");
Glib::RefPtr<Gio::Menu> gmenu = Glib::RefPtr<Gio::Menu>::cast_dynamic(object);
Gtk::MenuBar* pMenuBar = Gtk::manage(new Gtk::MenuBar(gmenu));
m_Box.pack_start(*pMenuBar, Gtk::PACK_SHRINK);

Gtk::Toolbar* toolbar = nullptr;
m_refBuilder->get_widget("toolbar", toolbar);
m_Box.pack_start(*toolbar, Gtk::PACK_SHRINK);]]>
</programlisting>

</sect1>


<sect1 id="sec-menus-popup"><title>Menus contextuels</title>
<para>Normalement, les menus sont seulement ajoutés à une fenêtre, mais ils peuvent aussi être temporairement affichés lors d'un clic de souris. Par exemple, un menu contextuel peut s'afficher si l'utilisateur clique sur un élément avec le bouton droit de la souris.</para>

<para>Par exemple :</para>
<programlisting lang="en">
<![CDATA[Glib::ustring ui_info =
  "<interface>"
  "  <menu id='menu-examplepopup'>"
  "    <section>"
  "      <item>"
  "        <attribute name='label' translatable='yes'>Edit</attribute>"
  "        <attribute name='action'>examplepopup.edit</attribute>"
  "      </item>"
  "      <item>"
  "        <attribute name='label' translatable='yes'>Process</attribute>"
  "        <attribute name='action'>examplepopup.process</attribute>"
  "      </item>"
  "      <item>"
  "        <attribute name='label' translatable='yes'>Remove</attribute>"
  "        <attribute name='action'>examplepopup.remove</attribute>"
  "      </item>"
  "    </section>"
  "  </menu>"
  "</interface>";

m_refBuilder->add_from_string(ui_info);

Glib::RefPtr<Glib::Object> object = m_refBuilder->get_object("menu-examplepopup");
Glib::RefPtr<Gio::Menu> gmenu = Glib::RefPtr<Gio::Menu>::cast_dynamic(object);
m_pMenuPopup = new Gtk::Menu(gmenu);]]>
</programlisting>

<para>Pour afficher le menu contextuel, utilisez la fonction membre <methodname>popup()</methodname> de la classe <classname>Gtk::Menu</classname>. Vous indiquez l'identifiant du bouton de souris et le délai d'activation tels que fournis par le signal <literal>button_press_event</literal>, signal que vous devez gérer de toutes façons. Par exemple :</para>
<programlisting lang="en">
<![CDATA[bool ExampleWindow::on_button_press_event(GdkEventButton* event)
{
  if( (event->type == GDK_BUTTON_PRESS) && (event->button == 3) )
  {
    if(!m_pMenuPopup->get_attach_widget())
      m_pMenuPopup->attach_to_widget(*this);

    m_pMenuPopup->popup(event->button, event->time);
    return true; //It has been handled.
  }
  else
    return false;
}]]>
</programlisting>

</sect1>

<sect1 id="sec-gio-resource">
<title lang="en">Gio::Resource and glib-compile-resources</title>

<para lang="en">
Applications and libraries often contain binary or textual data that is
really part of the application, rather than user data. For instance
<classname>Gtk::Builder</classname> <filename class="extension">.glade</filename> files,
splashscreen images, <classname>Gio::Menu</classname> markup xml, CSS files,
icons, etc. These are often shipped as files in <filename class="directory">$datadir/appname</filename>,
or manually included as literal strings in the code.
</para>
<para lang="en">
The <classname>Gio::Resource</classname> API and the <application>glib-compile-resources</application>
program provide a convenient and efficient alternative to this, which has some nice properties. You
maintain the files as normal files, so it's easy to edit them, but during the build the files
are combined into a binary bundle that is linked into the executable. This means that loading
the resource files is efficient (as they are already in memory, shared with other instances) and
simple (no need to check for things like I/O errors or locate the files in the filesystem). It
also makes it easier to create relocatable applications.
</para>
<para lang="en">
Resource bundles are created by the <ulink url="https://developer.gnome.org/gio/stable/glib-compile-resources.html">glib-compile-resources</ulink>
program which takes an xml file that describes the bundle, and a set of files that the xml references.
These are combined into a binary resource bundle.
</para>
<para lang="en"><ulink url="http://developer.gnome.org/glibmm/2.50/classGio_1_1Resource.html">Gio::Resource Reference</ulink></para>
<para lang="en">
An example:
<programlisting lang="en">
<![CDATA[<?xml version="1.0" encoding="UTF-8"?>
<gresources>
  <gresource prefix="/toolbar">
    <file preprocess="xml-stripblanks">toolbar.glade</file>
    <file>rain.png</file>
  </gresource>
</gresources>]]>
</programlisting>
This will create a resource bundle with the files
<itemizedlist>
  <listitem><para lang="en"><filename>/toolbar/toolbar.glade</filename></para></listitem>
  <listitem><para lang="en"><filename>/toolbar/rain.png</filename></para></listitem>
</itemizedlist>
</para>
<para lang="en">
You can then use <application>glib-compile-resources</application> to compile the xml to a binary bundle
that you can load with <methodname>Gio::Resource::create_from_file()</methodname>.
However, it's more common to use the <parameter class="command">--generate-source</parameter>
argument to create a C source file to link directly into your application. E.g.
<screen lang="en">$ glib-compile-resources --target=resources.c --generate-source toolbar.gresource.xml</screen>
</para>
<para lang="en">
Once a <classname>Gio::Resource</classname> has been created and registered all the data
in it can be accessed globally in the process by using API calls like
<methodname>Gio::Resource::open_stream_from_global_resources()</methodname>
to stream the data or <methodname>Gio::Resource::lookup_data_in_global_resources()</methodname>
to get a direct pointer to the data. You can also use URIs like <uri>resource:///toolbar/rain.png</uri>
with <classname>Gio::File</classname> to access the resource data.
</para>
<para lang="en">
Often you don't need a <classname>Gio::Resource</classname> instance,
because resource data can be loaded with methods such as
<methodname>Gdk::Pixbuf::create_from_resource()</methodname>,
<methodname>Gtk::Builder::add_from_resource()</methodname> and
<methodname>Gtk::Image::set_from_resource()</methodname>.
</para>

</sect1>

<sect1 id="sec-menus-examples">
    <title>Exemples</title>

<sect2 id="menu-example-main"><title lang="en">Application Menu and Main Menu example</title>
<para lang="en">
This program contains an application menu, a menubar and a toolbar.
Classes are derived from <classname>Gtk::Application</classname> and
<classname>Gtk::ApplicationWindow</classname>.
</para>

<figure id="figure-menus-mainmenu">
  <title lang="en">App and Main Menu</title>
  <screenshot>
    <graphic format="PNG" fileref="figures/main_menu.png"/>
  </screenshot>
</figure>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/menus/main_menu/?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>examplewindow.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLEWINDOW_H
#define GTKMM_EXAMPLEWINDOW_H

#include &lt;gtkmm.h&gt;

class ExampleWindow : public Gtk::ApplicationWindow
{
public:
  ExampleWindow();
  virtual ~ExampleWindow();

protected:
  //Signal handlers:
  void on_menu_others();

  void on_menu_choices(const Glib::ustring&amp; parameter);
  void on_menu_choices_other(int parameter);
  void on_menu_toggle();

  //Child widgets:
  Gtk::Box m_Box;

  Glib::RefPtr&lt;Gtk::Builder&gt; m_refBuilder;

  //Two sets of choices:
  Glib::RefPtr&lt;Gio::SimpleAction&gt; m_refChoice;
  Glib::RefPtr&lt;Gio::SimpleAction&gt; m_refChoiceOther;

  Glib::RefPtr&lt;Gio::SimpleAction&gt; m_refToggle;
};

#endif //GTKMM_EXAMPLEWINDOW_H
</programlisting>
<para lang="en">File: <filename>exampleapplication.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLEAPPLICATION_H
#define GTKMM_EXAMPLEAPPLICATION_H

#include &lt;gtkmm.h&gt;

class ExampleApplication : public Gtk::Application
{
protected:
  ExampleApplication();

public:
  static Glib::RefPtr&lt;ExampleApplication&gt; create();

protected:
  //Overrides of default signal handlers:
  void on_startup() override;
  void on_activate() override;

private:
  void create_window();

  void on_window_hide(Gtk::Window* window);
  void on_menu_file_new_generic();
  void on_menu_file_quit();
  void on_menu_help_about();

  Glib::RefPtr&lt;Gtk::Builder&gt; m_refBuilder;
};

#endif /* GTKMM_EXAMPLEAPPLICATION_H */
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "exampleapplication.h"

int main(int argc, char* argv[])
{
  auto application = ExampleApplication::create();

  // Start the application, showing the initial window,
  // and opening extra windows for any files that it is asked to open,
  // for instance as a command-line parameter.
  // run() will return when the last window has been closed by the user.
  const int status = application-&gt;run(argc, argv);
  return status;
}
</programlisting>
<para lang="en">File: <filename>exampleapplication.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "exampleapplication.h"
#include "examplewindow.h"
#include &lt;iostream&gt;

ExampleApplication::ExampleApplication()
: Gtk::Application("org.gtkmm.example.main_menu")
{
  Glib::set_application_name("Main Menu Example");
}

Glib::RefPtr&lt;ExampleApplication&gt; ExampleApplication::create()
{
  return Glib::RefPtr&lt;ExampleApplication&gt;(new ExampleApplication());
}

void ExampleApplication::on_startup()
{
  //Call the base class's implementation:
  Gtk::Application::on_startup();

  //Create actions for menus and toolbars.
  //We can use add_action() because Gtk::Application derives from Gio::ActionMap.

  //File|New sub menu:
  add_action("newstandard",
    sigc::mem_fun(*this, &amp;ExampleApplication::on_menu_file_new_generic));

  add_action("newfoo",
    sigc::mem_fun(*this, &amp;ExampleApplication::on_menu_file_new_generic));

  add_action("newgoo",
    sigc::mem_fun(*this, &amp;ExampleApplication::on_menu_file_new_generic));

  //File menu:
  add_action("quit", sigc::mem_fun(*this, &amp;ExampleApplication::on_menu_file_quit));

  //Help menu:
  add_action("about", sigc::mem_fun(*this, &amp;ExampleApplication::on_menu_help_about));

  m_refBuilder = Gtk::Builder::create();

  //Layout the actions in a menubar and an application menu:
  Glib::ustring ui_info =
    "&lt;interface&gt;"
    "  &lt;!-- menubar --&gt;"
    "  &lt;menu id='menu-example'&gt;"
    "    &lt;submenu&gt;"
    "      &lt;attribute name='label' translatable='yes'&gt;_File&lt;/attribute&gt;"
    "      &lt;section&gt;"
    "        &lt;item&gt;"
    "          &lt;attribute name='label' translatable='yes'&gt;New _Standard&lt;/attribute&gt;"
    "          &lt;attribute name='action'&gt;app.newstandard&lt;/attribute&gt;"
    "          &lt;attribute name='accel'&gt;&amp;lt;Primary&amp;gt;n&lt;/attribute&gt;"
    "        &lt;/item&gt;"
    "        &lt;item&gt;"
    "          &lt;attribute name='label' translatable='yes'&gt;New _Foo&lt;/attribute&gt;"
    "          &lt;attribute name='action'&gt;app.newfoo&lt;/attribute&gt;"
    "        &lt;/item&gt;"
    "        &lt;item&gt;"
    "          &lt;attribute name='label' translatable='yes'&gt;New _Goo&lt;/attribute&gt;"
    "          &lt;attribute name='action'&gt;app.newgoo&lt;/attribute&gt;"
    "        &lt;/item&gt;"
    "      &lt;/section&gt;"
    "      &lt;section&gt;"
    "        &lt;item&gt;"
    "          &lt;attribute name='label' translatable='yes'&gt;_Quit&lt;/attribute&gt;"
    "          &lt;attribute name='action'&gt;app.quit&lt;/attribute&gt;"
    "          &lt;attribute name='accel'&gt;&amp;lt;Primary&amp;gt;q&lt;/attribute&gt;"
    "        &lt;/item&gt;"
    "      &lt;/section&gt;"
    "    &lt;/submenu&gt;"
    "    &lt;submenu&gt;"
    "      &lt;attribute name='label' translatable='yes'&gt;_Edit&lt;/attribute&gt;"
    "      &lt;section&gt;"
    "        &lt;item&gt;"
    "          &lt;attribute name='label' translatable='yes'&gt;_Copy&lt;/attribute&gt;"
    "          &lt;attribute name='action'&gt;win.copy&lt;/attribute&gt;"
    "          &lt;attribute name='accel'&gt;&amp;lt;Primary&amp;gt;c&lt;/attribute&gt;"
    "        &lt;/item&gt;"
    "        &lt;item&gt;"
    "          &lt;attribute name='label' translatable='yes'&gt;_Paste&lt;/attribute&gt;"
    "          &lt;attribute name='action'&gt;win.paste&lt;/attribute&gt;"
    "          &lt;attribute name='accel'&gt;&amp;lt;Primary&amp;gt;v&lt;/attribute&gt;"
    "        &lt;/item&gt;"
    "        &lt;item&gt;"
    "          &lt;attribute name='label' translatable='yes'&gt;_Something&lt;/attribute&gt;"
    "          &lt;attribute name='action'&gt;win.something&lt;/attribute&gt;"
    "        &lt;/item&gt;"
    "      &lt;/section&gt;"
    "    &lt;/submenu&gt;"
    "    &lt;submenu&gt;"
    "      &lt;attribute name='label' translatable='yes'&gt;_Choices&lt;/attribute&gt;"
    "      &lt;section&gt;"
    "        &lt;item&gt;"
    "          &lt;attribute name='label' translatable='yes'&gt;Choice _A&lt;/attribute&gt;"
    "          &lt;attribute name='action'&gt;win.choice&lt;/attribute&gt;"
    "          &lt;attribute name='target'&gt;a&lt;/attribute&gt;"
    "        &lt;/item&gt;"
    "        &lt;item&gt;"
    "          &lt;attribute name='label' translatable='yes'&gt;Choice _B&lt;/attribute&gt;"
    "          &lt;attribute name='action'&gt;win.choice&lt;/attribute&gt;"
    "          &lt;attribute name='target'&gt;b&lt;/attribute&gt;"
    "        &lt;/item&gt;"
    "      &lt;/section&gt;"
    "    &lt;/submenu&gt;"
    "    &lt;submenu&gt;"
    "      &lt;attribute name='label' translatable='yes'&gt;_Other Choices&lt;/attribute&gt;"
    "      &lt;section&gt;"
    "        &lt;item&gt;"
    "          &lt;attribute name='label' translatable='yes'&gt;Choice 1&lt;/attribute&gt;"
    "          &lt;attribute name='action'&gt;win.choiceother&lt;/attribute&gt;"
    "          &lt;attribute name='target' type='i'&gt;1&lt;/attribute&gt;"
    "        &lt;/item&gt;"
    "        &lt;item&gt;"
    "          &lt;attribute name='label' translatable='yes'&gt;Choice 2&lt;/attribute&gt;"
    "          &lt;attribute name='action'&gt;win.choiceother&lt;/attribute&gt;"
    "          &lt;attribute name='target' type='i'&gt;2&lt;/attribute&gt;"
    "        &lt;/item&gt;"
    "      &lt;/section&gt;"
    "      &lt;section&gt;"
    "        &lt;item&gt;"
    "          &lt;attribute name='label' translatable='yes'&gt;Some Toggle&lt;/attribute&gt;"
    "          &lt;attribute name='action'&gt;win.sometoggle&lt;/attribute&gt;"
    "        &lt;/item&gt;"
    "      &lt;/section&gt;"
    "    &lt;/submenu&gt;"
    "    &lt;submenu&gt;"
    "      &lt;attribute name='label' translatable='yes'&gt;_Help&lt;/attribute&gt;"
    "      &lt;section&gt;"
    "        &lt;item&gt;"
    "          &lt;attribute name='label' translatable='yes'&gt;_About&lt;/attribute&gt;"
    "          &lt;attribute name='action'&gt;win.about&lt;/attribute&gt;"
    "        &lt;/item&gt;"
    "      &lt;/section&gt;"
    "    &lt;/submenu&gt;"
    "  &lt;/menu&gt;"
    ""
    "  &lt;!-- application menu --&gt;"
    "  &lt;menu id='appmenu'&gt;"
    "    &lt;submenu&gt;"
    "      &lt;attribute name='label' translatable='yes'&gt;_File&lt;/attribute&gt;"
    "      &lt;section&gt;"
    "        &lt;item&gt;"
    "          &lt;attribute name='label' translatable='yes'&gt;New _Standard&lt;/attribute&gt;"
    "          &lt;attribute name='action'&gt;app.newstandard&lt;/attribute&gt;"
    "          &lt;attribute name='accel'&gt;&amp;lt;Primary&amp;gt;n&lt;/attribute&gt;"
    "        &lt;/item&gt;"
    "        &lt;item&gt;"
    "          &lt;attribute name='label' translatable='yes'&gt;New _Foo&lt;/attribute&gt;"
    "          &lt;attribute name='action'&gt;app.newfoo&lt;/attribute&gt;"
    "        &lt;/item&gt;"
    "        &lt;item&gt;"
    "          &lt;attribute name='label' translatable='yes'&gt;New _Goo&lt;/attribute&gt;"
    "          &lt;attribute name='action'&gt;app.newgoo&lt;/attribute&gt;"
    "        &lt;/item&gt;"
    "      &lt;/section&gt;"
    "      &lt;section&gt;"
    "        &lt;item&gt;"
    "          &lt;attribute name='label' translatable='yes'&gt;_Quit&lt;/attribute&gt;"
    "          &lt;attribute name='action'&gt;app.quit&lt;/attribute&gt;"
    "          &lt;attribute name='accel'&gt;&amp;lt;Primary&amp;gt;q&lt;/attribute&gt;"
    "        &lt;/item&gt;"
    "      &lt;/section&gt;"
    "    &lt;/submenu&gt;"
    "    &lt;submenu&gt;"
    "      &lt;attribute name='label' translatable='yes'&gt;_Help&lt;/attribute&gt;"
    "      &lt;section&gt;"
    "        &lt;item&gt;"
    "          &lt;attribute name='label' translatable='yes'&gt;_About&lt;/attribute&gt;"
    "          &lt;attribute name='action'&gt;app.about&lt;/attribute&gt;"
    "        &lt;/item&gt;"
    "      &lt;/section&gt;"
    "    &lt;/submenu&gt;"
    "  &lt;/menu&gt;"
    "&lt;/interface&gt;";

  try
  {
    m_refBuilder-&gt;add_from_string(ui_info);
  }
  catch (const Glib::Error&amp; ex)
  {
    std::cerr &lt;&lt; "Building menus failed: " &lt;&lt; ex.what();
  }

  //Get the menubar and the app menu, and add them to the application:
  auto object = m_refBuilder-&gt;get_object("menu-example");
  auto gmenu = Glib::RefPtr&lt;Gio::Menu&gt;::cast_dynamic(object);
  object = m_refBuilder-&gt;get_object("appmenu");
  auto appMenu = Glib::RefPtr&lt;Gio::Menu&gt;::cast_dynamic(object);
  if (!(gmenu &amp;&amp; appMenu)) {
    g_warning("GMenu or AppMenu not found");
  }
  else
  {
    set_app_menu(appMenu);
    set_menubar(gmenu);
  }
}

void ExampleApplication::on_activate()
{
  //std::cout &lt;&lt; "debug1: " &lt;&lt; G_STRFUNC &lt;&lt; std::endl;
  // The application has been started, so let's show a window.
  // A real application might want to reuse this window in on_open(),
  // when asked to open a file, if no changes have been made yet.
  create_window();
}

void ExampleApplication::create_window()
{
  auto win = new ExampleWindow();

  //Make sure that the application runs for as long this window is still open:
  add_window(*win);

  //Delete the window when it is hidden.
  //That's enough for this simple example.
  win-&gt;signal_hide().connect(sigc::bind&lt;Gtk::Window*&gt;(
    sigc::mem_fun(*this, &amp;ExampleApplication::on_window_hide), win));

  win-&gt;show_all();
}

void ExampleApplication::on_window_hide(Gtk::Window* window)
{
  delete window;
}

void ExampleApplication::on_menu_file_new_generic()
{
  std::cout &lt;&lt; "A File|New menu item was selected." &lt;&lt; std::endl;
}

void ExampleApplication::on_menu_file_quit()
{
  std::cout &lt;&lt; G_STRFUNC &lt;&lt; std::endl;
  quit(); // Not really necessary, when Gtk::Widget::hide() is called.

  // Gio::Application::quit() will make Gio::Application::run() return,
  // but it's a crude way of ending the program. The window is not removed
  // from the application. Neither the window's nor the application's
  // destructors will be called, because there will be remaining reference
  // counts in both of them. If we want the destructors to be called, we
  // must remove the window from the application. One way of doing this
  // is to hide the window.
  std::vector&lt;Gtk::Window*&gt; windows = get_windows();
  if (windows.size() &gt; 0)
    windows[0]-&gt;hide(); // In this simple case, we know there is only one window.
}

void ExampleApplication::on_menu_help_about()
{
  std::cout &lt;&lt; "App|Help|About was selected." &lt;&lt; std::endl;
}
</programlisting>
<para lang="en">File: <filename>examplewindow.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;iostream&gt;

ExampleWindow::ExampleWindow()
: Gtk::ApplicationWindow(),
  m_Box(Gtk::ORIENTATION_VERTICAL)
{
  set_title("Main menu example");
  set_default_size(300, 100);

  // ExampleApplication displays the menubar. Other stuff, such as a toolbar,
  // is put into the box.
  add(m_Box);

  // Create actions for menus and toolbars.
  // We can use add_action() because Gtk::ApplicationWindow derives from Gio::ActionMap.
  // This Action Map uses a "win." prefix for the actions.
  // Therefore, for instance, "win.copy", is used in ExampleApplication::on_startup()
  // to layout the menu.

  //Edit menu:
  add_action("copy", sigc::mem_fun(*this, &amp;ExampleWindow::on_menu_others));
  add_action("paste", sigc::mem_fun(*this, &amp;ExampleWindow::on_menu_others));
  add_action("something", sigc::mem_fun(*this, &amp;ExampleWindow::on_menu_others));

  //Choices menus, to demonstrate Radio items,
  //using our convenience methods for string and int radio values:
  m_refChoice = add_action_radio_string("choice",
    sigc::mem_fun(*this, &amp;ExampleWindow::on_menu_choices), "a");

  m_refChoiceOther = add_action_radio_integer("choiceother",
    sigc::mem_fun(*this, &amp;ExampleWindow::on_menu_choices_other), 1);

  m_refToggle = add_action_bool("sometoggle",
    sigc::mem_fun(*this, &amp;ExampleWindow::on_menu_toggle), false);

  //Help menu:
  add_action("about", sigc::mem_fun(*this, &amp;ExampleWindow::on_menu_others));

  //Create the toolbar and add it to a container widget:

  m_refBuilder = Gtk::Builder::create();

  Glib::ustring ui_info =
    "&lt;!-- Generated with glade 3.18.3 --&gt;"
    "&lt;interface&gt;"
    "  &lt;requires lib='gtk+' version='3.4'/&gt;"
    "  &lt;object class='GtkToolbar' id='toolbar'&gt;"
    "    &lt;property name='visible'&gt;True&lt;/property&gt;"
    "    &lt;property name='can_focus'&gt;False&lt;/property&gt;"
    "    &lt;child&gt;"
    "      &lt;object class='GtkToolButton' id='toolbutton_new'&gt;"
    "        &lt;property name='visible'&gt;True&lt;/property&gt;"
    "        &lt;property name='can_focus'&gt;False&lt;/property&gt;"
    "        &lt;property name='tooltip_text' translatable='yes'&gt;New Standard&lt;/property&gt;"
    "        &lt;property name='action_name'&gt;app.newstandard&lt;/property&gt;"
    "        &lt;property name='icon_name'&gt;document-new&lt;/property&gt;"
    "      &lt;/object&gt;"
    "      &lt;packing&gt;"
    "        &lt;property name='expand'&gt;False&lt;/property&gt;"
    "        &lt;property name='homogeneous'&gt;True&lt;/property&gt;"
    "      &lt;/packing&gt;"
    "    &lt;/child&gt;"
    "    &lt;child&gt;"
    "      &lt;object class='GtkToolButton' id='toolbutton_quit'&gt;"
    "        &lt;property name='visible'&gt;True&lt;/property&gt;"
    "        &lt;property name='can_focus'&gt;False&lt;/property&gt;"
    "        &lt;property name='tooltip_text' translatable='yes'&gt;Quit&lt;/property&gt;"
    "        &lt;property name='action_name'&gt;app.quit&lt;/property&gt;"
    "        &lt;property name='icon_name'&gt;application-exit&lt;/property&gt;"
    "      &lt;/object&gt;"
    "      &lt;packing&gt;"
    "        &lt;property name='expand'&gt;False&lt;/property&gt;"
    "        &lt;property name='homogeneous'&gt;True&lt;/property&gt;"
    "      &lt;/packing&gt;"
    "    &lt;/child&gt;"
    "  &lt;/object&gt;"
    "&lt;/interface&gt;";

  try
  {
    m_refBuilder-&gt;add_from_string(ui_info);
  }
  catch (const Glib::Error&amp; ex)
  {
    std::cerr &lt;&lt; "Building toolbar failed: " &lt;&lt;  ex.what();
  }

  Gtk::Toolbar* toolbar = nullptr;
  m_refBuilder-&gt;get_widget("toolbar", toolbar);
  if (!toolbar)
    g_warning("GtkToolbar not found");
  else
    m_Box.pack_start(*toolbar, Gtk::PACK_SHRINK);
}

ExampleWindow::~ExampleWindow()
{
}

void ExampleWindow::on_menu_others()
{
  std::cout &lt;&lt; "A menu item was selected." &lt;&lt; std::endl;
}

void ExampleWindow::on_menu_choices(const Glib::ustring&amp; parameter)
{
  //The radio action's state does not change automatically:
  m_refChoice-&gt;change_state(parameter);

  Glib::ustring message;
  if (parameter == "a")
    message = "Choice a was selected.";
  else
    message = "Choice b was selected.";

  std::cout &lt;&lt; message &lt;&lt; std::endl;
}

void ExampleWindow::on_menu_choices_other(int parameter)
{
  //The radio action's state does not change automatically:
  m_refChoiceOther-&gt;change_state(parameter);

  Glib::ustring message;
  if (parameter == 1)
    message = "Choice 1 was selected.";
  else
    message = "Choice 2 was selected.";

  std::cout &lt;&lt; message &lt;&lt; std::endl;
}

void ExampleWindow::on_menu_toggle()
{
  bool active = false;
  m_refToggle-&gt;get_state(active);

  //The toggle action's state does not change automatically:
  active = !active;
  m_refToggle-&gt;change_state(active);

  Glib::ustring message;
  if (active)
    message = "Toggle is active.";
  else
    message = "Toggle is not active.";

  std::cout &lt;&lt; message &lt;&lt; std::endl;
}
</programlisting>
<!-- end inserted example code -->

</sect2>

<sect2 id="menu-example-main2"><title>Exemple de menu principal</title>
<para lang="en">
This program contains a menubar and a toolbar.
A class is derived from <classname>Gtk::Window</classname>.
</para>

<figure id="figure-menus-mainmenu2">
  <title>Menu principal</title>
  <screenshot>
    <graphic format="PNG" fileref="figures/menus_and_toolbars.png"/>
  </screenshot>
</figure>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/menus_and_toolbars?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>examplewindow.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLEWINDOW_H
#define GTKMM_EXAMPLEWINDOW_H

#include &lt;gtkmm.h&gt;

class ExampleWindow : public Gtk::Window
{
public:
  ExampleWindow(const Glib::RefPtr&lt;Gtk::Application&gt;&amp; app);
  virtual ~ExampleWindow();

private:
  //Signal handlers:
  void on_action_file_new();
  void on_action_file_quit();
  void on_action_others();
  void on_action_toggle();

  //Child widgets:
  Gtk::Box m_Box;

  Glib::RefPtr&lt;Gtk::Builder&gt; m_refBuilder;
  Glib::RefPtr&lt;Gio::SimpleActionGroup&gt; m_refActionGroup;
  Glib::RefPtr&lt;Gio::SimpleAction&gt; m_refActionRain;
};

#endif //GTKMM_EXAMPLEWINDOW_H
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include &lt;gtkmm.h&gt;
#include "examplewindow.h"

int main(int argc, char *argv[])
{
  auto app = Gtk::Application::create(argc, argv, "org.gtkmm.example");

  ExampleWindow window(app);

  //Shows the window and returns when it is closed.
  return app-&gt;run(window);
}
</programlisting>
<para lang="en">File: <filename>examplewindow.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;gtkmm.h&gt;
#include &lt;iostream&gt;

ExampleWindow::ExampleWindow(const Glib::RefPtr&lt;Gtk::Application&gt;&amp; app)
: m_Box(Gtk::ORIENTATION_VERTICAL)
{
  set_title("main_menu example");
  set_default_size(200, 200);

  add(m_Box); //We can put a MenuBar at the top of the box and other stuff below it.

  //Define the actions:
  m_refActionGroup = Gio::SimpleActionGroup::create();

  m_refActionGroup-&gt;add_action("new",
    sigc::mem_fun(*this, &amp;ExampleWindow::on_action_file_new) );
  m_refActionGroup-&gt;add_action("open",
    sigc::mem_fun(*this, &amp;ExampleWindow::on_action_others) );


  m_refActionRain = m_refActionGroup-&gt;add_action_bool("rain",
    sigc::mem_fun(*this, &amp;ExampleWindow::on_action_toggle),
    false);

  m_refActionGroup-&gt;add_action("quit",
    sigc::mem_fun(*this, &amp;ExampleWindow::on_action_file_quit) );

  m_refActionGroup-&gt;add_action("cut",
    sigc::mem_fun(*this, &amp;ExampleWindow::on_action_others) );
  m_refActionGroup-&gt;add_action("copy",
    sigc::mem_fun(*this, &amp;ExampleWindow::on_action_others) );
  m_refActionGroup-&gt;add_action("paste",
    sigc::mem_fun(*this, &amp;ExampleWindow::on_action_others) );

  insert_action_group("example", m_refActionGroup);

  //Define how the actions are presented in the menus and toolbars:
  m_refBuilder = Gtk::Builder::create();

  //Layout the actions in a menubar and toolbar:
  const char* ui_info =
    "&lt;interface&gt;"
    "  &lt;menu id='menubar'&gt;"
    "    &lt;submenu&gt;"
    "      &lt;attribute name='label' translatable='yes'&gt;_File&lt;/attribute&gt;"
    "      &lt;section&gt;"
    "        &lt;item&gt;"
    "          &lt;attribute name='label' translatable='yes'&gt;_New&lt;/attribute&gt;"
    "          &lt;attribute name='action'&gt;example.new&lt;/attribute&gt;"
    "          &lt;attribute name='accel'&gt;&amp;lt;Primary&amp;gt;n&lt;/attribute&gt;"
    "        &lt;/item&gt;"
    "        &lt;item&gt;"
    "          &lt;attribute name='label' translatable='yes'&gt;_Open&lt;/attribute&gt;"
    "          &lt;attribute name='action'&gt;example.open&lt;/attribute&gt;"
    "          &lt;attribute name='accel'&gt;&amp;lt;Primary&amp;gt;o&lt;/attribute&gt;"
    "        &lt;/item&gt;"
    "      &lt;/section&gt;"
    "      &lt;section&gt;"
    "        &lt;item&gt;"
    "          &lt;attribute name='label' translatable='yes'&gt;Rain&lt;/attribute&gt;"
    "          &lt;attribute name='action'&gt;example.rain&lt;/attribute&gt;"
    "        &lt;/item&gt;"
    "      &lt;/section&gt;"
    "      &lt;section&gt;"
    "        &lt;item&gt;"
    "          &lt;attribute name='label' translatable='yes'&gt;_Quit&lt;/attribute&gt;"
    "          &lt;attribute name='action'&gt;example.quit&lt;/attribute&gt;"
    "          &lt;attribute name='accel'&gt;&amp;lt;Primary&amp;gt;q&lt;/attribute&gt;"
    "        &lt;/item&gt;"
    "      &lt;/section&gt;"
    "    &lt;/submenu&gt;"
    "    &lt;submenu&gt;"
    "      &lt;attribute name='label' translatable='yes'&gt;_Edit&lt;/attribute&gt;"
    "      &lt;item&gt;"
    "        &lt;attribute name='label' translatable='yes'&gt;_Cut&lt;/attribute&gt;"
    "        &lt;attribute name='action'&gt;example.cut&lt;/attribute&gt;"
    "        &lt;attribute name='accel'&gt;&amp;lt;Primary&amp;gt;x&lt;/attribute&gt;"
    "      &lt;/item&gt;"
    "      &lt;item&gt;"
    "        &lt;attribute name='label' translatable='yes'&gt;_Copy&lt;/attribute&gt;"
    "        &lt;attribute name='action'&gt;example.copy&lt;/attribute&gt;"
    "        &lt;attribute name='accel'&gt;&amp;lt;Primary&amp;gt;c&lt;/attribute&gt;"
    "      &lt;/item&gt;"
    "      &lt;item&gt;"
    "        &lt;attribute name='label' translatable='yes'&gt;_Paste&lt;/attribute&gt;"
    "        &lt;attribute name='action'&gt;example.paste&lt;/attribute&gt;"
    "        &lt;attribute name='accel'&gt;&amp;lt;Primary&amp;gt;v&lt;/attribute&gt;"
    "      &lt;/item&gt;"
    "    &lt;/submenu&gt;"
    "  &lt;/menu&gt;"
    "&lt;/interface&gt;";

  // When the menubar is a child of a Gtk::Window, keyboard accelerators are not
  // automatically fetched from the Gio::Menu.
  // See the examples/book/menus/main_menu example for an alternative way of
  // adding the menubar when using Gtk::ApplicationWindow.
  // Gtk::Application::set_accel_for_action() is new in gtkmm 3.11.9.
  app-&gt;set_accel_for_action("example.new", "&lt;Primary&gt;n");
  app-&gt;set_accel_for_action("example.open", "&lt;Primary&gt;o");
  app-&gt;set_accel_for_action("example.quit", "&lt;Primary&gt;q");
  app-&gt;set_accel_for_action("example.cut", "&lt;Primary&gt;x");
  app-&gt;set_accel_for_action("example.copy", "&lt;Primary&gt;c");
  app-&gt;set_accel_for_action("example.paste", "&lt;Primary&gt;v");

  try
  {
    m_refBuilder-&gt;add_from_string(ui_info);
    m_refBuilder-&gt;add_from_resource("/toolbar/toolbar.glade");
  }
  catch(const Glib::Error&amp; ex)
  {
    std::cerr &lt;&lt; "Building menus and toolbar failed: " &lt;&lt;  ex.what();
  }

  //Get the menubar:
  auto object = m_refBuilder-&gt;get_object("menubar");
  auto gmenu = Glib::RefPtr&lt;Gio::Menu&gt;::cast_dynamic(object);
  if (!gmenu)
    g_warning("GMenu not found");
  else
  {
    auto pMenuBar = Gtk::manage(new Gtk::MenuBar(gmenu));

    //Add the MenuBar to the window:
    m_Box.pack_start(*pMenuBar, Gtk::PACK_SHRINK);
  }

  //Get the toolbar and add it to a container widget:
  Gtk::Toolbar* toolbar = nullptr;
  m_refBuilder-&gt;get_widget("toolbar", toolbar);
  if (!toolbar)
    g_warning("GtkToolbar not found");
  else
    m_Box.pack_start(*toolbar, Gtk::PACK_SHRINK);

  show_all_children();
}

ExampleWindow::~ExampleWindow()
{
}

void ExampleWindow::on_action_file_quit()
{
  hide(); //Closes the main window to stop the app-&gt;run().
}

void ExampleWindow::on_action_file_new()
{
   std::cout &lt;&lt; "A File|New menu item was selected." &lt;&lt; std::endl;
}

void ExampleWindow::on_action_others()
{
  std::cout &lt;&lt; "A menu item was selected." &lt;&lt; std::endl;
}

void ExampleWindow::on_action_toggle()
{
  std::cout &lt;&lt; "The toggle menu item was selected." &lt;&lt; std::endl;

  bool active = false;
  m_refActionRain-&gt;get_state(active);

  //The toggle action's state does not change automatically:
  active = !active;
  m_refActionRain-&gt;change_state(active);

  Glib::ustring message;
  if(active)
    message = "Toggle is active.";
  else
    message = "Toggle is not active";

  std::cout &lt;&lt; message &lt;&lt; std::endl;
}
</programlisting>
<para lang="en">File: <filename>toolbar.gresource.xml</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
&lt;?xml version="1.0" encoding="UTF-8"?&gt;
&lt;gresources&gt;
  &lt;gresource prefix="/toolbar"&gt;
    &lt;file preprocess="xml-stripblanks"&gt;toolbar.glade&lt;/file&gt;
    &lt;file&gt;rain.png&lt;/file&gt;
  &lt;/gresource&gt;
&lt;/gresources&gt;
</programlisting>
<!-- end inserted example code -->

</sect2>

<sect2 id="menu-example-popup"><title>Exemple de menu contextuel</title>

<figure id="figure-menus-popup">
  <title>Menu contextuel</title>
  <screenshot>
    <graphic format="PNG" fileref="figures/menu_popup.png"/>
  </screenshot>
</figure>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/menus/popup/?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>examplewindow.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLEWINDOW_H
#define GTKMM_EXAMPLEWINDOW_H

#include &lt;gtkmm.h&gt;

class ExampleWindow : public Gtk::Window
{
public:
  ExampleWindow();
  virtual ~ExampleWindow();

protected:
  //Signal handlers:
  bool on_button_press_event(GdkEventButton* button_event) override;

  void on_menu_file_popup_generic();

  //Child widgets:
  Gtk::Box m_Box;
  Gtk::EventBox m_EventBox;
  Gtk::Label m_Label;

  Glib::RefPtr&lt;Gtk::Builder&gt; m_refBuilder;

  Gtk::Menu* m_pMenuPopup;
};

#endif //GTKMM_EXAMPLEWINDOW_H
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;gtkmm/application.h&gt;

int main(int argc, char *argv[])
{
  auto app = Gtk::Application::create(argc, argv, "org.gtkmm.example");

  ExampleWindow window;

  //Shows the window and returns when it is closed.
  return app-&gt;run(window);
}
</programlisting>
<para lang="en">File: <filename>examplewindow.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;iostream&gt;

ExampleWindow::ExampleWindow()
: m_Box(Gtk::ORIENTATION_VERTICAL),
  m_Label("Right-click to see the popup menu."),
  m_pMenuPopup(nullptr)
{
  set_title("popup example");
  set_default_size(200, 200);

  add(m_Box);

  //Add an event box that can catch button_press events:
  m_Box.pack_start(m_EventBox);
  m_EventBox.signal_button_press_event().connect(sigc::mem_fun(*this,
              &amp;ExampleWindow::on_button_press_event) );

  m_EventBox.add(m_Label);

  //Create actions:

  //Fill menu:

  auto refActionGroup =
    Gio::SimpleActionGroup::create();

  //File|New sub menu:
  //These menu actions would normally already exist for a main menu, because a
  //context menu should not normally contain menu items that are only available
  //via a context menu.

  refActionGroup-&gt;add_action("edit",
    sigc::mem_fun(*this, &amp;ExampleWindow::on_menu_file_popup_generic));

  refActionGroup-&gt;add_action("process", //TODO: How to specify "&lt;control&gt;P" as an accelerator.
    sigc::mem_fun(*this, &amp;ExampleWindow::on_menu_file_popup_generic));

  refActionGroup-&gt;add_action("remove",
    sigc::mem_fun(*this, &amp;ExampleWindow::on_menu_file_popup_generic));

  insert_action_group("examplepopup", refActionGroup);


  m_refBuilder = Gtk::Builder::create();

  //Layout the actions in a menubar and toolbar:
  Glib::ustring ui_info =
    "&lt;interface&gt;"
    "  &lt;menu id='menu-examplepopup'&gt;"
    "    &lt;section&gt;"
    "      &lt;item&gt;"
    "        &lt;attribute name='label' translatable='yes'&gt;Edit&lt;/attribute&gt;"
    "        &lt;attribute name='action'&gt;examplepopup.edit&lt;/attribute&gt;"
    "      &lt;/item&gt;"
    "      &lt;item&gt;"
    "        &lt;attribute name='label' translatable='yes'&gt;Process&lt;/attribute&gt;"
    "        &lt;attribute name='action'&gt;examplepopup.process&lt;/attribute&gt;"
    "      &lt;/item&gt;"
    "      &lt;item&gt;"
    "        &lt;attribute name='label' translatable='yes'&gt;Remove&lt;/attribute&gt;"
    "        &lt;attribute name='action'&gt;examplepopup.remove&lt;/attribute&gt;"
    "      &lt;/item&gt;"
    "    &lt;/section&gt;"
    "  &lt;/menu&gt;"
    "&lt;/interface&gt;";

  try
  {
    m_refBuilder-&gt;add_from_string(ui_info);
  }
  catch(const Glib::Error&amp; ex)
  {
    std::cerr &lt;&lt; "building menus failed: " &lt;&lt;  ex.what();
  }

  //Get the menu:
  auto object =
    m_refBuilder-&gt;get_object("menu-examplepopup");
  auto gmenu =
    Glib::RefPtr&lt;Gio::Menu&gt;::cast_dynamic(object);
  if(!gmenu)
    g_warning("GMenu not found");

  m_pMenuPopup = new Gtk::Menu(gmenu);

  show_all_children();
}

ExampleWindow::~ExampleWindow()
{
}

void ExampleWindow::on_menu_file_popup_generic()
{
   std::cout &lt;&lt; "A popup menu item was selected." &lt;&lt; std::endl;
}

bool ExampleWindow::on_button_press_event(GdkEventButton* button_event)
{
  if( (button_event-&gt;type == GDK_BUTTON_PRESS) &amp;&amp; (button_event-&gt;button == 3) )
  {
    if(!m_pMenuPopup-&gt;get_attach_widget())
    {
      m_pMenuPopup-&gt;attach_to_widget(*this);
    }

    if(m_pMenuPopup)
      m_pMenuPopup-&gt;popup_at_pointer((GdkEvent*)button_event);

      // Menu::popup_at_pointer() is new in gtkmm 3.22.
      // If you have an older revision, try this:
      //m_pMenuPopup-&gt;popup(button_event-&gt;button, button_event-&gt;time);

    return true; //It has been handled.
  }
  else
    return false;
}

</programlisting>
<!-- end inserted example code -->

</sect2>

</sect1>

</chapter>

<chapter id="chapter-toolpalette">
<title>Palette d'outils</title>

<para>L'objet <classname>ToolPalette</classname> est semblable à un objet <classname>Toolbar</classname>, mais il peut comporter un quadrillage d'éléments classés en groupements. L'utilisateur peut masquer ou développer chaque groupement. Comme dans une barre d'outils, les éléments sont affichés sous forme d'icônes uniquement, texte uniquement ou icônes avec texte.</para>
<para>Il est possible de faire glisser, ou simplement activer, les éléments d'un objet <classname>ToolPalette</classname>. Par exemple, l'utilisateur peut faire glisser des objets sur un canevas pour y créer de nouveaux éléments, ou bien, il peut cliquer sur un élément pour activer une taille de plume donnée dans une application de tracé.</para>
<para lang="en"><classname>ToolItemGroup</classname>s should be added to the tool palette via the base class's <function>Gtk::Container::add()</function> method, for instance like so:
</para>
<para>
<programlisting>
Gtk::ToolItemGroup* group_brushes =
  Gtk::manage(new Gtk::ToolItemGroup("Brosses"));
m_ToolPalette.add(*group_brushes);
</programlisting>
</para>
<para>Les éléments <classname>Gtk::ToolItem</classname> sont ensuite ajoutés au groupement. Ainsi :</para>
<para>
<programlisting>
Gtk::ToolButton* button = Gtk::manage(new Gtk::ToolButton(icon, "Grande"));
button-&gt;set_tooltip_text("Grande brosse);
group_brushes-&gt;insert(*button);
</programlisting>
</para>
<para>Vous pouvez après cela gérer le signal <literal>clicked</literal> sur l'objet <classname>ToolButton</classname>. Autre possibilité, vous pouvez autoriser le glisser-déposer de l'élément sur un autre élément graphique avec <methodname>Gtk::ToolPalette::add_drag_dest()</methodname>, puis en faisant appel à <methodname>Gtk::ToolPalette::get_drag_item()</methodname> dans le gestionnaire du signal <literal>drag_data_received</literal> de l'autre élément graphique.</para>

<para lang="en"><ulink url="http://developer.gnome.org/gtkmm/3.22/classGtk_1_1ToolPalette.html">ToolPalette Reference</ulink></para>
<para lang="en"><ulink url="http://developer.gnome.org/gtkmm/3.22/classGtk_1_1ToolItemGroup.html">ToolItemGroup Reference</ulink></para>
<para lang="en"><ulink url="http://developer.gnome.org/gtkmm/3.22/classGtk_1_1ToolItem.html">ToolItem Reference</ulink></para>

<sect1 id="toolpallete-dranganddrop">
<title>Glisser-déposer</title>
<para lang="en">Call <methodname>add_drag_dest()</methodname> to allow items or groups to be dragged from the tool palette to a particular destination widget. You can then use <methodname>get_drag_item()</methodname> to discover which ToolItem or ToolItemGroup is being dragged. You can use <literal>dynamic_cast</literal> to discover whether it is an item or a group. For instance, you might use this in your <literal>drag_data_received</literal> signal handler, to add a dropped item, or to show a suitable icon while dragging.</para>
<para>Consultez le chapitre <link linkend="chapter-draganddrop">Glisser-déposer</link> pour des considérations générales sur cette fonctionnalité avec gtkmm.</para>
</sect1>

<sect1 id="toolpalette-example"><title>Exemple de palette d'outils</title>

<para>Dans cet exemple, des objets <classname>ToolPalette</classname> et <classname>DrawingArea</classname> sont associés à une fenêtre. L'utilisateur est autorisé à faire un glisser-déposer depuis la palette d'outils sur la surface de tracé. La palette d'outils contient divers groupes d'éléments. Des boîtes combinées permettent à l'utilisateur de changer le style et l'orientation de la palette d'outils.</para>

<figure id="figure-toolpalette">
  <title>Palette d'outils</title>
  <screenshot>
    <graphic format="PNG" fileref="figures/toolpalette.png"/>
  </screenshot>
</figure>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/toolpalette/?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>examplewindow.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLEWINDOW_H
#define GTKMM_EXAMPLEWINDOW_H

#include &lt;gtkmm.h&gt;
#include "canvas.h"

class ExampleWindow : public Gtk::Window
{
public:
  ExampleWindow();
  virtual ~ExampleWindow();

private:

  void load_icon_items();
  void load_toggle_items();
  void load_special_items();

  //Signal handlers:
  void on_combo_orientation_changed();
  void on_combo_style_changed();

  //Tree model columns:
  class ModelColumnsOrientation : public Gtk::TreeModel::ColumnRecord
  {
  public:

    ModelColumnsOrientation()
    { add(m_col_value); add(m_col_name); }

    Gtk::TreeModelColumn&lt;Gtk::Orientation&gt; m_col_value;
    Gtk::TreeModelColumn&lt;Glib::ustring&gt; m_col_name;
  };

  ModelColumnsOrientation m_ColumnsOrientation;

  //Tree model columns:
  class ModelColumnsStyle : public Gtk::TreeModel::ColumnRecord
  {
  public:

    ModelColumnsStyle()
    { add(m_col_value); add(m_col_name); }

    Gtk::TreeModelColumn&lt;int&gt; m_col_value; //We use int to also allow -1
    Gtk::TreeModelColumn&lt;Glib::ustring&gt; m_col_name;
  };

  ModelColumnsStyle m_ColumnsStyle;


  //Child widgets:
  Gtk::Box m_VBox;
  Gtk::Box m_HBox;
  Gtk::ComboBox m_ComboOrientation;
  Glib::RefPtr&lt;Gtk::ListStore&gt; m_refTreeModelOrientation;
  Gtk::ComboBox m_ComboStyle;
  Glib::RefPtr&lt;Gtk::ListStore&gt; m_refTreeModelStyle;
  Gtk::ToolPalette m_ToolPalette;
  Gtk::ScrolledWindow m_ScrolledWindowPalette;
  Gtk::ScrolledWindow m_ScrolledWindowCanvas;
  Canvas m_Canvas;
};

#endif //GTKMM_EXAMPLEWINDOW_H
</programlisting>
<para lang="en">File: <filename>canvas.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLE_CANVAS_H
#define GTKMM_EXAMPLE_CANVAS_H

#include &lt;gtkmm.h&gt;

// This little canvas class is only here
// because gtkmm does not have a canvas class yet.
// Applications should probably use GooCanvas::Canvas (goocanvasmm) instead.
class Canvas : public Gtk::DrawingArea
{
public:
  Canvas();
  virtual ~Canvas();

private:

  class CanvasItem
  {
  public:
    CanvasItem(Gtk::Widget* canvas, Gtk::ToolButton* button, double x, double y)
    {
      Glib::ustring icon_name(button-&gt;get_icon_name());
      if (icon_name.empty())
        icon_name = button-&gt;get_label();

      auto icon_theme = Gtk::IconTheme::get_for_screen(canvas-&gt;get_screen());
      int width = 0;
      int height = 0; //ignored
      Gtk::IconSize::lookup(Gtk::ICON_SIZE_DIALOG, width, height);
      this-&gt;m_pixbuf = icon_theme-&gt;load_icon(icon_name, width, Gtk::ICON_LOOKUP_GENERIC_FALLBACK);
      this-&gt;m_x = x;
      this-&gt;m_y = y;
    }

    Glib::RefPtr&lt;Gdk::Pixbuf&gt; m_pixbuf;
    double m_x, m_y;
  };

  void item_draw(const CanvasItem *item,
    const Cairo::RefPtr&lt;Cairo::Context&gt;&amp; cr,
    bool preview);

  bool on_draw(const Cairo::RefPtr&lt;Cairo::Context&gt;&amp; cr) override;
  void on_drag_data_received(const Glib::RefPtr&lt;Gdk::DragContext&gt;&amp; context,
    int x, int y, const Gtk::SelectionData&amp; selection_data, guint info, guint time) override;
  bool on_drag_motion(const Glib::RefPtr&lt;Gdk::DragContext&gt;&amp; context, int x, int y, guint time) override;
  bool on_drag_drop(const Glib::RefPtr&lt;Gdk::DragContext&gt;&amp; context, int x, int y, guint time) override;
  void on_drag_leave(const Glib::RefPtr&lt;Gdk::DragContext&gt;&amp; context, guint time) override;

  bool m_drag_data_requested_for_drop; //So we know what to do in on_drag_data_received().
  CanvasItem* m_drop_item;

  typedef std::vector&lt;CanvasItem*&gt; type_vec_items;
  type_vec_items m_canvas_items;
};

#endif //GTKMM_EXAMPLE_CANVAS_H
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;gtkmm/application.h&gt;

int main(int argc, char *argv[])
{
  auto app = Gtk::Application::create(argc, argv, "org.gtkmm.example");

  ExampleWindow window;

  //Shows the window and returns when it is closed.
  return app-&gt;run(window);
}
</programlisting>
<para lang="en">File: <filename>canvas.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "canvas.h"
#include &lt;iostream&gt;

Canvas::Canvas()
: m_drag_data_requested_for_drop(false),
  m_drop_item(nullptr)
{
  set_app_paintable();
}

Canvas::~Canvas()
{
  while(!m_canvas_items.empty())
  {
    auto iter = m_canvas_items.begin();
    auto item = *iter;
    delete item;
    m_canvas_items.erase(iter);
  }

  delete m_drop_item;
}

void Canvas::item_draw(const CanvasItem *item,
  const Cairo::RefPtr&lt;Cairo::Context&gt;&amp; cr,
  bool preview)
{
  if(!item || !item-&gt;m_pixbuf)
    return;

  const double cx = item-&gt;m_pixbuf-&gt;get_width();
  const double cy = item-&gt;m_pixbuf-&gt;get_height();

  Gdk::Cairo::set_source_pixbuf(cr,
    item-&gt;m_pixbuf,
    item-&gt;m_x - cx * 0.5, item-&gt;m_y - cy * 0.5);

  if(preview)
    cr-&gt;paint_with_alpha(0.6);
  else
    cr-&gt;paint();
}

bool Canvas::on_draw(const Cairo::RefPtr&lt;Cairo::Context&gt;&amp; cr)
{
  cr-&gt;set_source_rgb(1.0, 1.0, 1.0);
  const Gtk::Allocation allocation = get_allocation();
  cr-&gt;rectangle(0, 0, allocation.get_width(), allocation.get_height());
  cr-&gt;fill();

  for(type_vec_items::iterator iter = m_canvas_items.begin();
    iter != m_canvas_items.end(); ++iter )
  {
    item_draw(*iter, cr, false);
  }

  if(m_drop_item)
    item_draw (m_drop_item, cr, true);

  return true;
}


bool Canvas::on_drag_motion(const Glib::RefPtr&lt;Gdk::DragContext&gt;&amp; context,
  int x, int y, guint time)
{
  m_drag_data_requested_for_drop = false; //It's for drag-motion instead.

  if(m_drop_item)
  {
    // We already have a drop indicator so just update its position.

    m_drop_item-&gt;m_x = x;
    m_drop_item-&gt;m_y = y;

    queue_draw();
    context-&gt;drag_status(Gdk::ACTION_COPY, time);
  }
  else
  {
    // Request DnD data for creating a drop indicator.
    // This will cause on_drag_data_received() to be called.
    const Glib::ustring target = drag_dest_find_target(context);

    if (target.empty())
      return false;

    drag_get_data(context, target, time);
  }

  Gtk::DrawingArea::on_drag_motion(context, x, y, time);
  return true;
}


void Canvas::on_drag_data_received(const Glib::RefPtr&lt;Gdk::DragContext&gt;&amp; context,
  int x, int y, const Gtk::SelectionData&amp; selection_data, guint info, guint time)
{
  // Find the tool button which is the source of this DnD operation.
  auto widget = drag_get_source_widget(context);

  auto drag_palette = dynamic_cast&lt;Gtk::ToolPalette*&gt;(widget);
  while(widget &amp;&amp; !drag_palette)
  {
    widget = widget-&gt;get_parent();
    drag_palette = dynamic_cast&lt;Gtk::ToolPalette*&gt;(widget);
  }

  Gtk::ToolItem* drag_item = nullptr;
  if(drag_palette)
    drag_item = drag_palette-&gt;get_drag_item(selection_data);

  // Create a drop indicator when a tool button was found:
  auto button = dynamic_cast&lt;Gtk::ToolButton*&gt;(drag_item);
  if(!button)
    return;

  delete m_drop_item;
  m_drop_item = nullptr;

  try
  {
    auto item = new CanvasItem(this, button, x, y);

    if(m_drag_data_requested_for_drop)
    {
      m_canvas_items.push_back(item);

      // Signal that the item was accepted and then redraw.
      context-&gt;drag_finish(true /* success */, false /* del */, time);
    }
    else
    {
      m_drop_item = item;

      // We are getting this data due to a request in drag_motion,
      // rather than due to a request in drag_drop, so we are just
      // supposed to call gdk_drag_status (), not actually paste in
      // the data.
      context-&gt;drag_status(Gdk::ACTION_COPY, time);
    }

    queue_draw();
  }
  catch (const Gtk::IconThemeError&amp; ex)
  {
    std::cerr &lt;&lt; "IconThemeError: " &lt;&lt; ex.what() &lt;&lt; std::endl;
  }

  Gtk::DrawingArea::on_drag_data_received(context, x, y, selection_data, info, time);
}


bool Canvas::on_drag_drop(const Glib::RefPtr&lt;Gdk::DragContext&gt;&amp; context, int /* x */, int /* y */, guint time)
{
  // Request DnD data for creating a dopped item.
  // This will cause on_drag_data_received() to be called.
  const Glib::ustring target = drag_dest_find_target(context);

  if (target.empty())
    return false;

  m_drag_data_requested_for_drop = true;
  drag_get_data(context, target, time);

  return true;
}

void Canvas::on_drag_leave(const Glib::RefPtr&lt;Gdk::DragContext&gt;&amp; context, guint time)
{
  //This signal is emitted to clean up the item used for drag-motion,
  //either when the cursor moves out of the widget or when we drop.

  if(!m_drop_item)
    return;

  delete m_drop_item;
  m_drop_item = nullptr;

  queue_draw();

  Gtk::DrawingArea::on_drag_leave(context, time);
}
</programlisting>
<para lang="en">File: <filename>examplewindow.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"


void ExampleWindow::load_icon_items()
{
  auto icon_theme = Gtk::IconTheme::get_for_screen(get_screen());

  typedef std::vector&lt;Glib::ustring&gt; type_stringvec;
  type_stringvec icon_names = icon_theme-&gt;list_icons();

  // Obtain the names of all contexts, and the icon names per context.
  type_stringvec contexts = icon_theme-&gt;list_contexts();
  std::sort(contexts.begin(), contexts.end());

  int requested_icon_size = 0;
  int requested_icon_height = 0; //ignored
  Gtk::IconSize::lookup(Gtk::ICON_SIZE_BUTTON, requested_icon_size, requested_icon_height);
  const guint max_icons_per_group = 10;

  for (type_stringvec::const_iterator iter = contexts.begin(); iter != contexts.end(); ++iter)
  {
    const Glib::ustring context_name = *iter;
    Gtk::ToolItemGroup* group =
      Gtk::manage(new Gtk::ToolItemGroup(context_name));
    m_ToolPalette.add(*group);

    // Iterate through the icon names, populating the ToolItemGroup as appropriate.
    type_stringvec icon_names_for_context = icon_theme-&gt;list_icons(context_name);
    std::sort(icon_names_for_context.begin(), icon_names_for_context.end());
    guint icons_count = 0;
    for (type_stringvec::const_iterator iconiter = icon_names_for_context.begin(); iconiter != icon_names_for_context.end(); ++iconiter)
    {
      const Glib::ustring icon_name = *iconiter;
      Glib::RefPtr&lt;Gdk::Pixbuf&gt; pixbuf;
      try
      {
        pixbuf = icon_theme-&gt;load_icon(icon_name, requested_icon_size, Gtk::ICON_LOOKUP_GENERIC_FALLBACK);
      }
      catch (const Gtk::IconThemeError&amp; /* ex */)
      {
        // Gtk::IconTheme::list_icons() may return some names of icons
        // that can't be loaded.
        continue;
      }

      // Skip large icons, just to make the ToolPalette look better.
      if (pixbuf-&gt;get_width() &gt; 2*requested_icon_size ||
          pixbuf-&gt;get_height() &gt; 2*requested_icon_size)
        continue;

      auto image = Gtk::manage(new Gtk::Image(pixbuf));
      auto button = Gtk::manage(new Gtk::ToolButton(*image, icon_name));
      button-&gt;set_tooltip_text(icon_name);
      button-&gt;set_is_important();
      group-&gt;insert(*button);

      // Prevent us having an insane number of icons:
      ++icons_count;
      if(icons_count &gt;= max_icons_per_group)
        break;
    }
  }
}


void ExampleWindow::load_toggle_items()
{
  auto group =
    Gtk::manage(new Gtk::ToolItemGroup("Radio Item"));
  m_ToolPalette.add(*group);

  Gtk::RadioToolButton::Group radio_group;

  for(int i = 1; i &lt;= 10; ++i)
  {
    const Glib::ustring label = Glib::ustring::compose("#%1", i);
    auto button = Gtk::manage(new Gtk::RadioToolButton());
    button-&gt;set_group(radio_group);
    button-&gt;set_label(label);

    group-&gt;insert(*button);
  }
}


static Gtk::ToolItem* create_entry_item(const Glib::ustring&amp; text)
{
  auto entry = Gtk::manage(new Gtk::Entry());
  entry-&gt;set_text(text);
  entry-&gt;set_width_chars(5);

  auto item = Gtk::manage(new Gtk::ToolItem());
  item-&gt;add(*entry);

  return item;
}

void ExampleWindow::load_special_items()
{
  auto group = Gtk::manage(new Gtk::ToolItemGroup());

  Gtk::Button *label_button = Gtk::manage(new Gtk::Button("Advanced Features"));
  label_button-&gt;show();
  group-&gt;set_label_widget(*label_button);
  m_ToolPalette.add(*group);

  auto item = create_entry_item ("homogeneous=false");
  group-&gt;insert(*item);
  //TODO: Add Gtk::Container::set_child_property().
  gtk_container_child_set (GTK_CONTAINER (group-&gt;gobj()), GTK_WIDGET (item-&gt;gobj()),
                           "homogeneous", FALSE, NULL);

  item = create_entry_item ("homogeneous=FALSE, expand=TRUE");
  group-&gt;insert(*item);
  gtk_container_child_set (GTK_CONTAINER (group-&gt;gobj()), GTK_WIDGET (item-&gt;gobj()),
                           "homogeneous", FALSE, "expand", TRUE,
                           NULL);

  item = create_entry_item ("homogeneous=FALSE, expand=TRUE, fill=FALSE");
  group-&gt;insert(*item);
  gtk_container_child_set (GTK_CONTAINER (group-&gt;gobj()), GTK_WIDGET (item-&gt;gobj()),
                           "homogeneous", FALSE, "expand", TRUE,
                           "fill", FALSE, NULL);

  item = create_entry_item ("homogeneous=FALSE, expand=TRUE, new-row=TRUE");
  group-&gt;insert(*item);
  gtk_container_child_set (GTK_CONTAINER (group-&gt;gobj()), GTK_WIDGET (item-&gt;gobj()),
                           "homogeneous", FALSE, "expand", TRUE,
                           "new-row", TRUE, NULL);

  Gtk::ToolButton *button = Gtk::manage(new Gtk::ToolButton());
  button-&gt;set_icon_name("go-up");
  button-&gt;set_tooltip_text("Show on vertical palettes only");
  group-&gt;insert(*button);
  button-&gt;set_visible_horizontal(false);

  button = Gtk::manage(new Gtk::ToolButton());
  button-&gt;set_icon_name("go-next");
  button-&gt;set_tooltip_text("Show on horizontal palettes only");
  group-&gt;insert(*button);
  button-&gt;set_visible_vertical(false);

  button = Gtk::manage(new Gtk::ToolButton());
  button-&gt;set_icon_name("edit-delete");
  button-&gt;set_tooltip_text("Do not show at all");
  button-&gt;set_no_show_all();
  group-&gt;insert(*button);
  button-&gt;set_visible_vertical(false);

  button = Gtk::manage(new Gtk::ToolButton());
  button-&gt;set_icon_name("view-fullscreen");
  button-&gt;set_tooltip_text("Expanded this item");
  group-&gt;insert(*button);
  gtk_container_child_set (GTK_CONTAINER (group-&gt;gobj()), GTK_WIDGET (button-&gt;gobj()),
                           "homogeneous", FALSE,
                           "expand", TRUE,
                           NULL);

  button = Gtk::manage(new Gtk::ToolButton());
  button-&gt;set_icon_name("help-contents");
  button-&gt;set_tooltip_text("A regular item");
  group-&gt;insert(*button);
}

ExampleWindow::ExampleWindow()
: m_VBox(Gtk::ORIENTATION_VERTICAL, 6),
  m_HBox(Gtk::ORIENTATION_HORIZONTAL, 6)
{
  set_title("Gtk::ToolPalette example");
  set_size_request(600, 600);
  set_border_width(6);

  add(m_VBox);

  //The Orientation ComboBox:
  m_refTreeModelOrientation = Gtk::ListStore::create(m_ColumnsOrientation);
  Gtk::TreeModel::Row row = *(m_refTreeModelOrientation-&gt;append());
  row[m_ColumnsOrientation.m_col_value] = Gtk::ORIENTATION_HORIZONTAL;
  row[m_ColumnsOrientation.m_col_name] = "Horizontal";\
  row = *(m_refTreeModelOrientation-&gt;append());
  row[m_ColumnsOrientation.m_col_value] = Gtk::ORIENTATION_VERTICAL;
  row[m_ColumnsOrientation.m_col_name] = "Vertical";
  m_ComboOrientation.set_model(m_refTreeModelOrientation);
  m_VBox.pack_start(m_ComboOrientation, Gtk::PACK_SHRINK);
  m_ComboOrientation.pack_start(m_ColumnsOrientation.m_col_name);
  m_ComboOrientation.signal_changed().connect(
    sigc::mem_fun(*this, &amp;ExampleWindow::on_combo_orientation_changed) );
  m_ComboOrientation.set_active(row);

  //The Style ComboBox:
  m_refTreeModelStyle = Gtk::ListStore::create(m_ColumnsStyle);
  row = *(m_refTreeModelStyle-&gt;append());
  row[m_ColumnsStyle.m_col_value] = Gtk::TOOLBAR_TEXT;
  row[m_ColumnsStyle.m_col_name] = "Text";\
  row = *(m_refTreeModelStyle-&gt;append());
  row[m_ColumnsStyle.m_col_value] = Gtk::TOOLBAR_BOTH;
  row[m_ColumnsStyle.m_col_name] = "Both";
  row = *(m_refTreeModelStyle-&gt;append());
  row[m_ColumnsStyle.m_col_value] = Gtk::TOOLBAR_BOTH_HORIZ;
  row[m_ColumnsStyle.m_col_name] = "Both: Horizontal";
  row = *(m_refTreeModelStyle-&gt;append());
  row[m_ColumnsStyle.m_col_value] = Gtk::TOOLBAR_ICONS;
  row[m_ColumnsStyle.m_col_name] = "Icons";
  row = *(m_refTreeModelStyle-&gt;append());
  row[m_ColumnsStyle.m_col_value] = -1; // A custom meaning for this demo.
  row[m_ColumnsStyle.m_col_name] = "Default";
  m_ComboStyle.set_model(m_refTreeModelStyle);
  m_VBox.pack_start(m_ComboStyle, Gtk::PACK_SHRINK);
  m_ComboStyle.pack_start(m_ColumnsStyle.m_col_name);
  m_ComboStyle.signal_changed().connect(
    sigc::mem_fun(*this, &amp;ExampleWindow::on_combo_style_changed) );
  m_ComboStyle.set_active(row);

  //Add and fill the ToolPalette:
  load_icon_items();
  load_toggle_items();
  load_special_items();

  m_VBox.pack_start(m_HBox, Gtk::PACK_EXPAND_WIDGET);

  m_ScrolledWindowPalette.set_policy(Gtk::POLICY_NEVER, Gtk::POLICY_AUTOMATIC);
  m_ScrolledWindowPalette.set_border_width(6);
  m_ScrolledWindowPalette.add(m_ToolPalette);
  m_HBox.pack_start(m_ScrolledWindowPalette);

  on_combo_orientation_changed();

  m_ScrolledWindowCanvas.set_policy(Gtk::POLICY_AUTOMATIC, Gtk::POLICY_ALWAYS);
  m_ScrolledWindowCanvas.set_border_width(6);
  m_ScrolledWindowCanvas.add(m_Canvas);
  m_ScrolledWindowCanvas.set_size_request(200, -1);
  m_HBox.pack_start(m_ScrolledWindowCanvas);

  m_ToolPalette.add_drag_dest(m_Canvas,
    Gtk::DEST_DEFAULT_HIGHLIGHT, Gtk::TOOL_PALETTE_DRAG_ITEMS, Gdk::ACTION_COPY);

  show_all_children();
}

ExampleWindow::~ExampleWindow()
{
}

void ExampleWindow::on_combo_orientation_changed()
{
  Gtk::TreeModel::iterator iter = m_ComboOrientation.get_active();
  if(!iter)
    return;

  Gtk::TreeModel::Row row = *iter;
  const Gtk::Orientation value = row[m_ColumnsOrientation.m_col_value];

  m_ToolPalette.set_orientation(value);

  if(value == Gtk::ORIENTATION_HORIZONTAL)
    m_ScrolledWindowPalette.set_policy(Gtk::POLICY_AUTOMATIC, Gtk::POLICY_NEVER);
  else
    m_ScrolledWindowPalette.set_policy(Gtk::POLICY_NEVER, Gtk::POLICY_AUTOMATIC);
}

void ExampleWindow::on_combo_style_changed()
{
  Gtk::TreeModel::iterator iter = m_ComboStyle.get_active();
  if(!iter)
    return;

  Gtk::TreeModel::Row row = *iter;
  const int value = row[m_ColumnsStyle.m_col_value];

  if(value == -1)
    m_ToolPalette.unset_style();
  else
    m_ToolPalette.set_style((Gtk::ToolbarStyle)value);
}

</programlisting>
<!-- end inserted example code -->

</sect1>

</chapter>

<chapter id="chapter-adjustment">
<title>Ajustements</title>

<para><application>gtkmm</application> dispose de nombreux éléments graphiques pouvant être visuellement ajustés avec la souris ou le clavier, tels les éléments graphiques <classname>Range</classname> (décrits dans le paragraphe <link linkend="chapter-range-widgets">Éléments graphiques à plage de réglage</link>). Il existe également un petit nombre d'éléments graphiques qui n'affichent qu'une partie ajustable d'une zone plus grande, comme l'élément graphique <classname>Viewport</classname>. Tous ces éléments graphiques sont adossés à un objet <classname>Gtk::Adjustment</classname> pour définir cette part commune du comportement de leur API.</para>

<para lang="en">
So that applications can react to changes, for instance when a user moves a
scrollbar, <classname>Gtk::Adjustment</classname> has a
<literal>value_changed</literal> signal. You can then use the
<methodname>get_value()</methodname> method to discover the new value.
</para>

<sect1 id="sec-creating-adjustment">
<title>Création d'un objet Adjustment</title>

<para lang="en">
The <classname>Gtk::Adjustment</classname> is created by its
<methodname>create()</methodname> method which is as follows:
</para>

<programlisting lang="en">Glib::RefPtr&lt;Gtk::Adjustment&gt; Gtk::Adjustment::create(
  double value,
  double lower,
  double upper,
  double step_increment = 1,
  double page_increment = 10,
  double page_size = 0);</programlisting>

<para lang="en">
The <parameter>value</parameter> argument is the initial value of the
adjustment, usually corresponding to the topmost or leftmost position of an
adjustable widget. The <parameter>lower</parameter> and
<parameter>upper</parameter> arguments specify the possible range of values
which the adjustment can hold. The
<parameter>step_increment</parameter> argument specifies the smaller of
the two increments by which the user can change the value, while the
<parameter>page_increment</parameter> is the larger one. The
<parameter>page_size</parameter> argument usually corresponds somehow to
the visible area of a panning widget. The <parameter>upper</parameter> argument
is used to represent the bottommost or rightmost coordinate in a panning
widget's child.
<!-- TODO: Investigate the upper argument properly. There was some unclear stuff about it not always being the upper value. -->
</para>

</sect1>

<sect1 id="sec-adjustments-easy">
<title>Facilité d'utilisation des objets Adjustment</title>

<para>Il est possible, grosso modo, de diviser les éléments graphiques à plage de réglage en, d'une part, ceux dont la structure d'ajustement utilise et nécessite des valeurs précises, et ceux, d'autre part, qui considèrent ces valeurs comme des nombres arbitraires.</para>
<para lang="en">
The group which treats the values as arbitrary numbers includes the
<classname>Range</classname> widgets (<classname>Scrollbar</classname> and
<classname>Scale</classname>), the <classname>ScaleButton</classname> widget,
and the <classname>SpinButton</classname> widget. These widgets  are typically
"adjusted" directly by the user with the mouse or keyboard. They will treat the
<parameter>lower</parameter> and <parameter>upper</parameter> values of an
adjustment as a range within which the user can manipulate the adjustment's
<parameter>value</parameter>. By default, they will only modify the
<parameter>value</parameter> of an adjustment.
</para>

<para>L'autre groupe comprend les éléments graphiques <classname>Viewport</classname> et <classname>ScrolledWindow</classname>. Tous ceux-ci utilisent des valeurs en pixels dans leur structure <literal>adjustment</literal>. Ils sont, en règle générale, « ajustés » indirectement à l'aide de barres de défilement. Comme tous les éléments graphiques utilisant des ajustements peuvent, soit créer leurs propres structures <literal>adjustement</literal>, soit utiliser celle qui leur est fournie, nous souhaiterons, en règle générale, laisser à cette catégorie particulière d'éléments graphiques le soin de créer elle-même leurs propres structures d'ajustement.</para>

<para>Si vous partagez une structure d'ajustement entre un élément Scrollbar et un élément TextView, la manipulation de la barre de défilement ajustera comme par magie l'élément TextView. Vous pouvez définir cela comme suit :</para>
<programlisting lang="en">// creates its own adjustments
Gtk::TextView textview;
// uses the newly-created adjustment for the scrollbar as well
Gtk::Scrollbar vscrollbar (textview.get_vadjustment(), Gtk::ORIENTATION_VERTICAL);</programlisting>

</sect1>

<sect1 id="sec-adjustment-internals">
<title>À l'intérieur des ajustements</title>

<para>Oui, dites-vous, c'est bien beau, mais que faire si je souhaite créer mes propres gestionnaires pour répondre à la modification par l'utilisateur d'un élément graphique <classname>Range</classname> ou <classname>SpinButton</classname>. Pour avoir accès à la valeur du paramètre <parameter>value</parameter> d'un <classname>Gtk::Adjustment</classname>, utilisez les fonctions membres <methodname>get_value()</methodname> et <methodname>set_value()</methodname>.</para>

<para>Comme mentionné plus haut, <classname>Gtk::Adjustment</classname> peut émettre des signaux. C'est pourquoi, bien entendu, les mises à jour se font automatiquement quand vous partagez un objet ajustement entre un <classname>Scrollbar</classname> et un autre élément graphique ajustable ; tous les éléments graphiques ajustables connectent leurs gestionnaires de signaux au signal <literal>value_changed</literal> de l'ajustement, comme pourrait le faire le programme.</para>

<para>Ainsi, par exemple, avec un élément graphique <classname>Scale</classname>, si vous voulez modifier la rotation d'une image chaque fois que <literal>value</literal> change, vous créez une fonction de rappel du type :</para>
<programlisting lang="en">void cb_rotate_picture (MyPicture* picture)
{
  picture-&gt;set_rotation(adj-&gt;get_value());
...</programlisting>
<para>et la connectez à l'ajustement de l'élément graphique <literal>Scale</literal> ainsi :</para>
<programlisting lang="en">adj-&gt;signal_value_changed().connect(sigc::bind&lt;MyPicture*&gt;(sigc::mem_fun(*this,
    &amp;cb_rotate_picture), picture));</programlisting>

<para>Que se passe-t-il quand un élément graphique reconfigure les champs <parameter>upper</parameter> ou <parameter>lower</parameter> de son <classname>Adjustment</classname>, ou bien, quand un utilisateur ajoute du texte dans un élément graphique texte ? Dans ce cas, l'élément graphique émet le signal <literal>changed</literal>.</para>

<para>Les éléments graphiques <classname>Range</classname> connectent habituellement à ce signal un gestionnaire qui modifie leur apparence pour refléter le changement — par exemple, la taille du curseur dans une barre de défilement va croître ou diminuer en proportion inverse de la différence entre les valeurs <parameter>lower</parameter> et <parameter>upper</parameter> de son <classname>Adjustment</classname>.</para>

<para>Vous n'aurez probablement pas besoin d'attacher un gestionnaire à ce signal, sauf si vous écrivez un nouveau type d'élément graphique à plage de réglage.</para>
<programlisting lang="en">adjustment-&gt;signal_changed();</programlisting>

</sect1>

</chapter>

<chapter id="chapter-widgets-without-xwindows">
<title>Éléments graphiques sans fenêtre-X</title>

<para>Certains éléments graphiques n'ont pas de fenêtre-X associée ; ils ne sont donc pas capables de recevoir les notifications des événements X. Autrement dit : les signaux décrits au paragraphe <link linkend="sec-xeventsignals">Signaux d'événements X</link> ne seront pas émis. Si vous souhaitez capturer des événements pour ces éléments graphiques, vous devez utiliser un conteneur spécial nommé <classname>Gtk::EventBox</classname> décrit au paragraphe <link linkend="sec-eventbox">EventBox</link>.</para>

<para>Voici une liste de quelques uns de ces éléments graphiques :</para>
<programlisting lang="en">Gtk::Alignment (deprecated from <application>gtkmm</application> version 3.14)
Gtk::Arrow (deprecated from <application>gtkmm</application> version 3.14)
Gtk::AspectFrame
Gtk::Bin
Gtk::Box
Gtk::Button
Gtk::CheckButton
Gtk::Fixed
Gtk::Frame
Gtk::Grid
Gtk::Image
Gtk::Label
Gtk::MenuItem
Gtk::Notebook
Gtk::Paned
Gtk::RadioButton
Gtk::Range
Gtk::ScrolledWindow
Gtk::Separator
Gtk::Table (deprecated from <application>gtkmm</application> version 3.4)
Gtk::Toolbar</programlisting>

<para>Ces éléments graphiques sont essentiellement utilisés pour l'agencement ou la décoration ; la plupart du temps, il ne sera donc pas nécessaire de capturer d'événements sur eux. Ils n'ont pas été pourvus d'une fenêtre-X intentionnellement pour améliorer la performance.</para>

<sect1 id="sec-eventbox">
<title>EventBox</title>

<para lang="en">
Some <application>gtkmm</application> widgets don't have associated X windows; they draw on
their parents' windows. Because of this, they cannot receive events.
Also, if they are incorrectly sized, they don't clip, so you can get
messy overwriting etc. To receive events on one of these widgets, you can place it
inside an <classname>EventBox</classname> widget and then call
<methodname>Gtk::Widget::set_events()</methodname> on the EventBox before showing it.</para>

<para>Même si le nom <classname>EventBox</classname> met en valeur l'aspect gestion des événements, cet élément graphique peut être utilisé pour la délimitation des contours (ou plus ; voir l'exemple ci-dessous).</para>
<!--
<para>TODO: Why don't they have X Windows - explain clipping.
Also, how does this affect platform such as Windows and MacOS that don't use X.
</para>
-->

<para>Le constructeur d'un objet <classname>Gtk::EventBox</classname> est :</para>

<programlisting>Gtk::EventBox();</programlisting>

<para>L'ajout d'un élément graphique enfant à un <classname>EventBox</classname> s'effectue avec :</para>

<programlisting>event_box.add(child_widget);</programlisting>

<para lang="en"><ulink url="http://developer.gnome.org/gtkmm/3.22/classGtk_1_1EventBox.html">Reference</ulink></para>

<sect2 id="eventbox-example">
<title>Exemple</title>
<para>L'exemple suivant montre deux utilisations d'un <classname>EventBox</classname> — création d'une étiquette tronquée dans une petite boîte et configuration pour qu'un clic de souris sur l'étiquette fasse quitter le programme. Le redimensionnement de la fenêtre révèle plus ou moins le contenu de l'étiquette.</para>

<figure id="figure-eventbox">
  <title>EventBox</title>
  <screenshot>
    <graphic format="PNG" fileref="figures/eventbox.png"/>
  </screenshot>
</figure>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/eventbox?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>examplewindow.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLEWINDOW_H
#define GTKMM_EXAMPLEWINDOW_H

#include &lt;gtkmm.h&gt;

class ExampleWindow : public Gtk::Window
{
public:
  ExampleWindow();
  virtual ~ExampleWindow();

protected:
  //Signal handlers:
  bool on_eventbox_button_press(GdkEventButton* button_event);

  //Child widgets:
  Gtk::EventBox m_EventBox;
  Gtk::Label m_Label;
};

#endif //GTKMM_EXAMPLEWINDOW_H
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;gtkmm/application.h&gt;

int main(int argc, char *argv[])
{
  auto app = Gtk::Application::create(argc, argv, "org.gtkmm.example");

  ExampleWindow window;

  //Shows the window and returns when it is closed.
  return app-&gt;run(window);
}
</programlisting>
<para lang="en">File: <filename>examplewindow.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"

ExampleWindow::ExampleWindow()
: m_Label("Click here to quit, quit, quit, quit, quit")
{
  set_title ("EventBox");
  set_border_width(10);

  add(m_EventBox);

  m_EventBox.add(m_Label);

  //Clip the label short:
  set_default_size(110, 20);
  m_Label.set_size_request(110, 20);
  m_Label.set_ellipsize(Pango::ELLIPSIZE_END);

  //And bind an action to it:
  m_EventBox.set_events(Gdk::BUTTON_PRESS_MASK);
  m_EventBox.signal_button_press_event().connect(
    sigc::mem_fun(*this, &amp;ExampleWindow::on_eventbox_button_press) );

  m_EventBox.set_tooltip_text("Click me!");

  show_all_children();
}

ExampleWindow::~ExampleWindow()
{
}

bool ExampleWindow::on_eventbox_button_press(GdkEventButton*)
{
  hide();
  return true;
}
</programlisting>
<!-- end inserted example code -->
</sect2>

</sect1>

</chapter>

<chapter id="chapter-dialogs">
<title>Boîtes de dialogue</title>

<para>Les boîtes de dialogue s'utilisent en tant que fenêtres accessoires pour donner des informations particulières ou pour poser des questions. Les fenêtres <classname>Gtk::Dialog</classname> contiennent des éléments graphiques pré-incorporés pour assurer une certaine cohérence ; elles disposent également d'une fonction membre <methodname>run()</methodname> bloquante jusqu'à ce que l'utilisateur ferme la boîte de dialogue.</para>

<para>Il y a plusieurs classes dérivées de <classname>Dialog</classname> ; vous les trouverez certainement utiles. <classname>Gtk::MessageDialog</classname> s'utilise pour la plupart des simples notifications. Mais, dans d'autres circonstances, vous aurez besoin de dériver vous-même vos propres classes de boîtes de dialogue pour obtenir des fonctionnalités plus élaborées.</para>

<para lang="en">
To pack widgets into a custom dialog, you should pack them into the
<classname>Gtk::Box</classname>, available via
<methodname>get_content_area()</methodname>. To just add a <classname>Button</classname>
to the bottom of the <classname>Dialog</classname>, you could use the
<methodname>add_button()</methodname> method.
</para>

<para lang="en">
The <methodname>run()</methodname> method returns an <literal>int</literal>. This
may be a value from the <literal>Gtk::ResponseType</literal> if the user
closed the dialog by clicking a standard button, or it could be the custom
response value that you specified when using <methodname>add_button()</methodname>.
</para>

<para lang="en"><ulink url="http://developer.gnome.org/gtkmm/3.22/classGtk_1_1Dialog.html">Reference</ulink></para>

<sect1 id="sec-dialogs-messagedialog"><title>Boîte de dialogue Message</title>
<para><classname>MessageDialog</classname> est une classe de commodité, utilisée pour créer des boîtes de dialogues destinées à des messages standards simples ; elles comportent un message, une icône et des boutons pour la réponse de l'utilisateur. Vous pouvez définir le type de message et le texte à afficher dans le constructeur, de même que les boutons standards à utiliser par l'intermédiaire de l'énumération <literal>Gtk::ButtonsType</literal>.</para>

<para lang="en"><ulink url="http://developer.gnome.org/gtkmm/3.22/classGtk_1_1MessageDialog.html">Reference</ulink></para>

<sect2 id="messagedialog-example">
<title>Exemple</title>

<figure id="figure-dialogs-messagedialog">
  <title>Boîte de dialogue Message</title>
  <screenshot>
    <graphic format="PNG" fileref="figures/dialogs_messagedialog.png"/>
  </screenshot>
</figure>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/dialogs/messagedialog?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>examplewindow.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLEWINDOW_H
#define GTKMM_EXAMPLEWINDOW_H

#include &lt;gtkmm.h&gt;

class ExampleWindow : public Gtk::Window
{
public:
  ExampleWindow();
  virtual ~ExampleWindow();

protected:
  //Signal handlers:
  void on_button_info_clicked();
  void on_button_question_clicked();

  //Child widgets:
  Gtk::ButtonBox m_ButtonBox;
  Gtk::Button m_Button_Info, m_Button_Question;
};

#endif //GTKMM_EXAMPLEWINDOW_H
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;gtkmm/application.h&gt;

int main(int argc, char *argv[])
{
  auto app = Gtk::Application::create(argc, argv, "org.gtkmm.example");

  ExampleWindow window;

  //Shows the window and returns when it is closed.
  return app-&gt;run(window);
}
</programlisting>
<para lang="en">File: <filename>examplewindow.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;gtkmm/messagedialog.h&gt;
#include &lt;iostream&gt;


ExampleWindow::ExampleWindow()
: m_ButtonBox(Gtk::ORIENTATION_VERTICAL),
  m_Button_Info("Show Info MessageDialog"),
  m_Button_Question("Show Question MessageDialog")
{
  set_title("Gtk::MessageDialog example");

  add(m_ButtonBox);

  m_ButtonBox.pack_start(m_Button_Info);
  m_Button_Info.signal_clicked().connect(sigc::mem_fun(*this,
              &amp;ExampleWindow::on_button_info_clicked) );

  m_ButtonBox.pack_start(m_Button_Question);
  m_Button_Question.signal_clicked().connect(sigc::mem_fun(*this,
              &amp;ExampleWindow::on_button_question_clicked) );

  show_all_children();
}

ExampleWindow::~ExampleWindow()
{
}

void ExampleWindow::on_button_info_clicked()
{
  Gtk::MessageDialog dialog(*this, "This is an INFO MessageDialog");
  dialog.set_secondary_text(
          "And this is the secondary text that explains things.");

  dialog.run();
}

void ExampleWindow::on_button_question_clicked()
{
  Gtk::MessageDialog dialog(*this, "This is a QUESTION MessageDialog",
          false /* use_markup */, Gtk::MESSAGE_QUESTION,
          Gtk::BUTTONS_OK_CANCEL);
  dialog.set_secondary_text(
          "And this is the secondary text that explains things.");

  int result = dialog.run();

  //Handle the response:
  switch(result)
  {
    case(Gtk::RESPONSE_OK):
    {
      std::cout &lt;&lt; "OK clicked." &lt;&lt; std::endl;
      break;
    }
    case(Gtk::RESPONSE_CANCEL):
    {
      std::cout &lt;&lt; "Cancel clicked." &lt;&lt; std::endl;
      break;
    }
    default:
    {
      std::cout &lt;&lt; "Unexpected button clicked." &lt;&lt; std::endl;
      break;
    }
  }
}
</programlisting>
<!-- end inserted example code -->
</sect2>

</sect1>

<sect1 id="sec-dialogs-filechooserdialog"><title>Boîte de dialogue Sélection de fichier</title>
<para>La boîte de dialogue de la classe <classname>FileChooserDialog</classname> convient pour une utilisation avec les éléments de menu « Ouvrir » ou « Enregistrer ».</para>
<para>La plupart des fonctions membres utiles de cette classe sont en fait dans la classe de base <classname>Gtk::FileChooser</classname>.</para>

<para lang="en"><ulink url="http://developer.gnome.org/gtkmm/3.22/classGtk_1_1FileChooserDialog.html">Reference</ulink></para>

<sect2 id="filechooserdialog-example">
<title>Exemple</title>

<figure id="figure-dialogs-filechooser">
  <title>Boîte de dialogue Sélection de fichier</title>
  <screenshot>
    <graphic format="PNG" fileref="figures/dialogs_filechooser.png"/>
  </screenshot>
</figure>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/dialogs/filechooserdialog?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>examplewindow.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLEWINDOW_H
#define GTKMM_EXAMPLEWINDOW_H

#include &lt;gtkmm.h&gt;

class ExampleWindow : public Gtk::Window
{
public:
  ExampleWindow();
  virtual ~ExampleWindow();

protected:
  //Signal handlers:
  void on_button_file_clicked();
  void on_button_folder_clicked();

  //Child widgets:
  Gtk::ButtonBox m_ButtonBox;
  Gtk::Button m_Button_File, m_Button_Folder;
};

#endif //GTKMM_EXAMPLEWINDOW_H
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;gtkmm/application.h&gt;

int main(int argc, char *argv[])
{
  auto app = Gtk::Application::create(argc, argv, "org.gtkmm.example");

  ExampleWindow window;

  //Shows the window and returns when it is closed.
  return app-&gt;run(window);
}
</programlisting>
<para lang="en">File: <filename>examplewindow.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;iostream&gt;


ExampleWindow::ExampleWindow()
: m_ButtonBox(Gtk::ORIENTATION_VERTICAL),
  m_Button_File("Choose File"),
  m_Button_Folder("Choose Folder")
{
  set_title("Gtk::FileSelection example");

  add(m_ButtonBox);

  m_ButtonBox.pack_start(m_Button_File);
  m_Button_File.signal_clicked().connect(sigc::mem_fun(*this,
              &amp;ExampleWindow::on_button_file_clicked) );

  m_ButtonBox.pack_start(m_Button_Folder);
  m_Button_Folder.signal_clicked().connect(sigc::mem_fun(*this,
              &amp;ExampleWindow::on_button_folder_clicked) );

  show_all_children();
}

ExampleWindow::~ExampleWindow()
{
}

void ExampleWindow::on_button_folder_clicked()
{
  Gtk::FileChooserDialog dialog("Please choose a folder",
          Gtk::FILE_CHOOSER_ACTION_SELECT_FOLDER);
  dialog.set_transient_for(*this);

  //Add response buttons the the dialog:
  dialog.add_button("_Cancel", Gtk::RESPONSE_CANCEL);
  dialog.add_button("Select", Gtk::RESPONSE_OK);

  int result = dialog.run();

  //Handle the response:
  switch(result)
  {
    case(Gtk::RESPONSE_OK):
    {
      std::cout &lt;&lt; "Select clicked." &lt;&lt; std::endl;
      std::cout &lt;&lt; "Folder selected: " &lt;&lt; dialog.get_filename()
          &lt;&lt; std::endl;
      break;
    }
    case(Gtk::RESPONSE_CANCEL):
    {
      std::cout &lt;&lt; "Cancel clicked." &lt;&lt; std::endl;
      break;
    }
    default:
    {
      std::cout &lt;&lt; "Unexpected button clicked." &lt;&lt; std::endl;
      break;
    }
  }
}

void ExampleWindow::on_button_file_clicked()
{
  Gtk::FileChooserDialog dialog("Please choose a file",
          Gtk::FILE_CHOOSER_ACTION_OPEN);
  dialog.set_transient_for(*this);

  //Add response buttons the the dialog:
  dialog.add_button("_Cancel", Gtk::RESPONSE_CANCEL);
  dialog.add_button("_Open", Gtk::RESPONSE_OK);

  //Add filters, so that only certain file types can be selected:

  auto filter_text = Gtk::FileFilter::create();
  filter_text-&gt;set_name("Text files");
  filter_text-&gt;add_mime_type("text/plain");
  dialog.add_filter(filter_text);

  auto filter_cpp = Gtk::FileFilter::create();
  filter_cpp-&gt;set_name("C/C++ files");
  filter_cpp-&gt;add_mime_type("text/x-c");
  filter_cpp-&gt;add_mime_type("text/x-c++");
  filter_cpp-&gt;add_mime_type("text/x-c-header");
  dialog.add_filter(filter_cpp);

  auto filter_any = Gtk::FileFilter::create();
  filter_any-&gt;set_name("Any files");
  filter_any-&gt;add_pattern("*");
  dialog.add_filter(filter_any);

  //Show the dialog and wait for a user response:
  int result = dialog.run();

  //Handle the response:
  switch(result)
  {
    case(Gtk::RESPONSE_OK):
    {
      std::cout &lt;&lt; "Open clicked." &lt;&lt; std::endl;

      //Notice that this is a std::string, not a Glib::ustring.
      std::string filename = dialog.get_filename();
      std::cout &lt;&lt; "File selected: " &lt;&lt;  filename &lt;&lt; std::endl;
      break;
    }
    case(Gtk::RESPONSE_CANCEL):
    {
      std::cout &lt;&lt; "Cancel clicked." &lt;&lt; std::endl;
      break;
    }
    default:
    {
      std::cout &lt;&lt; "Unexpected button clicked." &lt;&lt; std::endl;
      break;
    }
  }
}
</programlisting>
<!-- end inserted example code -->
</sect2>
</sect1>

<sect1 id="sec-color-selection-dialog"><title lang="en">ColorChooserDialog</title>
<para lang="en">
The <classname>ColorChooserDialog</classname> allows the user to choose a
color. The <classname>ColorButton</classname> opens a color selection dialog
when it is clicked.
</para>

<para lang="en"><ulink url="http://developer.gnome.org/gtkmm/3.22/classGtk_1_1ColorChooserDialog.html">Reference</ulink></para>

<sect2 id="colorchooserdialog-example">
<title>Exemple</title>

<figure id="figure-dialogs-colorchooserdialog">
  <title lang="en">ColorChooserDialog</title>
  <screenshot>
    <graphic format="PNG" fileref="figures/dialogs_colorchooserdialog.png"/>
  </screenshot>
</figure>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/dialogs/colorchooserdialog?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>examplewindow.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLEWINDOW_H
#define GTKMM_EXAMPLEWINDOW_H

#include &lt;gtkmm.h&gt;

class ExampleWindow : public Gtk::Window
{
public:
  ExampleWindow();
  virtual ~ExampleWindow();

protected:
  //Signal handlers:
  void on_color_button_color_set();
  void on_button_dialog_clicked();
  bool on_drawing_area_draw(const Cairo::RefPtr&lt;Cairo::Context&gt;&amp; cr);

  //Child widgets:
  Gtk::Box m_VBox;
  Gtk::ColorButton m_ColorButton;
  Gtk::Button m_Button_Dialog;
  Gtk::DrawingArea m_DrawingArea; //To show the color.

  Gdk::RGBA m_Color;
};

#endif //GTKMM_EXAMPLEWINDOW_H
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;gtkmm/application.h&gt;

int main(int argc, char *argv[])
{
  auto app = Gtk::Application::create(argc, argv, "org.gtkmm.example");

  ExampleWindow window;

  //Shows the window and returns when it is closed.
  return app-&gt;run(window);
}
</programlisting>
<para lang="en">File: <filename>examplewindow.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;iostream&gt;

ExampleWindow::ExampleWindow()
: m_VBox(Gtk::ORIENTATION_VERTICAL, 5),
  m_Button_Dialog("Choose Color")
{
  set_title("Gtk::ColorChooserDialog example");
  set_default_size(200, 200);

  add(m_VBox);

  m_VBox.pack_start(m_ColorButton, Gtk::PACK_SHRINK);
  m_ColorButton.signal_color_set().connect(sigc::mem_fun(*this,
    &amp;ExampleWindow::on_color_button_color_set) );

  m_VBox.pack_start(m_Button_Dialog, Gtk::PACK_SHRINK);
  m_Button_Dialog.signal_clicked().connect(sigc::mem_fun(*this,
    &amp;ExampleWindow::on_button_dialog_clicked) );

  //Set start color:
  m_Color.set_red(0.0);
  m_Color.set_green(0.0);
  m_Color.set_blue(1.0);
  m_Color.set_alpha(1.0); //opaque
  m_ColorButton.set_rgba(m_Color);

  m_VBox.pack_start(m_DrawingArea);
  m_DrawingArea.signal_draw().connect(sigc::mem_fun(*this,
    &amp;ExampleWindow::on_drawing_area_draw));

  show_all_children();
}

ExampleWindow::~ExampleWindow()
{
}

void ExampleWindow::on_color_button_color_set()
{
  //Store the chosen color:
  m_Color = m_ColorButton.get_rgba();
}

void ExampleWindow::on_button_dialog_clicked()
{
  Gtk::ColorChooserDialog dialog("Please choose a color");
  dialog.set_transient_for(*this);

  //Get the previously selected color:
  dialog.set_rgba(m_Color);

  const int result = dialog.run();

  //Handle the response:
  switch(result)
  {
    case Gtk::RESPONSE_OK:
    {
      //Store the chosen color:
      m_Color = dialog.get_rgba();
      m_ColorButton.set_rgba(m_Color);
      break;
    }
    case Gtk::RESPONSE_CANCEL:
    {
      std::cout &lt;&lt; "Cancel clicked." &lt;&lt; std::endl;
      break;
    }
    default:
    {
      std::cout &lt;&lt; "Unexpected button clicked: " &lt;&lt; result &lt;&lt; std::endl;
      break;
    }
  }
}

bool ExampleWindow::on_drawing_area_draw(const Cairo::RefPtr&lt;Cairo::Context&gt;&amp; cr)
{
  Gdk::Cairo::set_source_rgba(cr, m_Color);
  cr-&gt;paint();

  return true;
}
</programlisting>
<!-- end inserted example code -->
</sect2>

</sect1>

<sect1 id="sec-font-chooser-dialog"><title lang="en">FontChooserDialog</title>
<para lang="en">
The <classname>FontChooserDialog</classname> allows the user to choose a
font. The <classname>FontButton</classname> opens a font chooser dialog
when it is clicked.
</para>

<para lang="en"><ulink url="http://developer.gnome.org/gtkmm/3.22/classGtk_1_1FontChooserDialog.html">Reference</ulink></para>

<sect2 id="fontchooserdialog-example">
<title>Exemple</title>

<figure id="figure-dialogs-fontchooserdialog">
  <title lang="en">FontChooserDialog</title>
  <screenshot>
    <graphic format="PNG" fileref="figures/dialogs_fontchooserdialog.png"/>
  </screenshot>
</figure>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/dialogs/fontchooserdialog?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>examplewindow.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLEWINDOW_H
#define GTKMM_EXAMPLEWINDOW_H

#include &lt;gtkmm.h&gt;

class ExampleWindow : public Gtk::Window
{
public:
  ExampleWindow();
  virtual ~ExampleWindow();

protected:
  //Signal handlers:
  void on_font_button_font_set();
  void on_button_dialog_clicked();

  //Child widgets:
  Gtk::ButtonBox m_ButtonBox;
  Gtk::FontButton m_FontButton;
  Gtk::Button m_Button_Dialog;
};

#endif //GTKMM_EXAMPLEWINDOW_H
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;gtkmm/application.h&gt;

int main(int argc, char *argv[])
{
  auto app = Gtk::Application::create(argc, argv, "org.gtkmm.example");

  ExampleWindow window;

  //Shows the window and returns when it is closed.
  return app-&gt;run(window);
}
</programlisting>
<para lang="en">File: <filename>examplewindow.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;iostream&gt;

ExampleWindow::ExampleWindow()
: m_ButtonBox(Gtk::ORIENTATION_VERTICAL),
  m_FontButton("Sans 10"),
  m_Button_Dialog("Choose Font")
{
  set_title("Gtk::FontChooserDialog example");

  add(m_ButtonBox);

  m_ButtonBox.pack_start(m_FontButton);
  m_FontButton.set_use_font(true);
  m_FontButton.set_use_size(true);
  m_FontButton.signal_font_set().connect(sigc::mem_fun(*this,
    &amp;ExampleWindow::on_font_button_font_set) );

  m_ButtonBox.pack_start(m_Button_Dialog);
  m_Button_Dialog.signal_clicked().connect(sigc::mem_fun(*this,
    &amp;ExampleWindow::on_button_dialog_clicked) );
  show_all_children();
}

ExampleWindow::~ExampleWindow()
{
}

void ExampleWindow::on_font_button_font_set()
{
  Glib::ustring font_name = m_FontButton.get_font_name();
  std::cout &lt;&lt; "Font chosen: " &lt;&lt; font_name &lt;&lt; std::endl;
}

void ExampleWindow::on_button_dialog_clicked()
{
  Gtk::FontChooserDialog dialog("Please choose a font", *this);

  //Get the previously selected font name from the FontButton:
  dialog.set_font(m_FontButton.get_font_name());

  int result = dialog.run();

  //Handle the response:
  switch(result)
  {
    case Gtk::RESPONSE_OK:
    {
      Glib::ustring font_name = dialog.get_font();
      std::cout &lt;&lt; "Font chosen: " &lt;&lt; font_name &lt;&lt; std::endl;
      m_FontButton.set_font_name(font_name);
      break;
    }
    case Gtk::RESPONSE_CANCEL:
    {
      std::cout &lt;&lt; "Cancel clicked." &lt;&lt; std::endl;
      break;
    }
    default:
    {
      std::cout &lt;&lt; "Unexpected button clicked: " &lt;&lt; result &lt;&lt; std::endl;
      break;
    }
  }
}
</programlisting>
<!-- end inserted example code -->
</sect2>

</sect1>

<sect1 id="sec-about-dialog"><title lang="en">Non-modal AboutDialog</title>
<para lang="en">
The <classname>AboutDialog</classname> offers a simple way to display information
about a program, like its logo, name, copyright, website and license.
</para>
<para lang="en">
Most dialogs in this chapter are modal, that is, they freeze the rest of
the application while they are shown. It's also possible to create a non-modal
dialog, which does not freeze other windows in the application.
The following example shows a non-modal <classname>AboutDialog</classname>. This is
perhaps not the kind of dialog you would normally make non-modal, but non-modal
dialogs can be useful in other cases. E.g. <application>gedit</application>'s
search-and-replace dialog is non-modal.
</para>

<para lang="en"><ulink url="http://developer.gnome.org/gtkmm/3.22/classGtk_1_1AboutDialog.html">Reference</ulink></para>

<sect2 id="aboutdialog-example">
<title>Exemple</title>

<figure id="figure-dialogs-about">
  <title lang="en">AboutDialog</title>
  <screenshot>
    <graphic format="PNG" fileref="figures/dialogs_about.png"/>
  </screenshot>
</figure>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/dialogs/aboutdialog?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>examplewindow.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLEWINDOW_H
#define GTKMM_EXAMPLEWINDOW_H

#include &lt;gtkmm.h&gt;

class ExampleWindow : public Gtk::Window
{
public:
  ExampleWindow();
  virtual ~ExampleWindow();

protected:
  //Signal handlers:
  void on_button_clicked();
  void on_about_dialog_response(int response_id);

  //Child widgets:
  Gtk::Box m_VBox;
  Gtk::Label m_Label;
  Gtk::ButtonBox m_ButtonBox;
  Gtk::Button m_Button;
  Gtk::AboutDialog m_Dialog;
};

#endif //GTKMM_EXAMPLEWINDOW_H
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;gtkmm/application.h&gt;

int main(int argc, char *argv[])
{
  auto app = Gtk::Application::create(argc, argv, "org.gtkmm.example");

  ExampleWindow window;

  //Shows the window and returns when it is closed.
  return app-&gt;run(window);
}
</programlisting>
<para lang="en">File: <filename>examplewindow.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;iostream&gt;

ExampleWindow::ExampleWindow()
: m_VBox(Gtk::ORIENTATION_VERTICAL),
  m_Label("The AboutDialog is non-modal. "
    "You can select parts of this text while the AboutDialog is shown."),
  m_ButtonBox(Gtk::ORIENTATION_VERTICAL),
  m_Button("Show AboutDialog")
{
  set_title("Gtk::AboutDialog example");

  add(m_VBox);

  m_VBox.pack_start(m_Label);
  m_Label.set_line_wrap(true);
  m_Label.set_selectable(true);

  m_VBox.pack_start(m_ButtonBox);
  m_ButtonBox.pack_start(m_Button);
  m_Button.signal_clicked().connect(sigc::mem_fun(*this,
              &amp;ExampleWindow::on_button_clicked) );

  m_Dialog.set_transient_for(*this);

  m_Dialog.set_logo(Gdk::Pixbuf::create_from_resource("/about/gtkmm_logo.gif", -1, 40, true));
  m_Dialog.set_program_name("Example application");
  m_Dialog.set_version("1.0.0");
  m_Dialog.set_copyright("Murray Cumming");
  m_Dialog.set_comments("This is just an example application.");
  m_Dialog.set_license("LGPL");

  m_Dialog.set_website("http://www.gtkmm.org");
  m_Dialog.set_website_label("gtkmm website");

  std::vector&lt;Glib::ustring&gt; list_authors;
  list_authors.push_back("Murray Cumming");
  list_authors.push_back("Somebody Else");
  list_authors.push_back("AN Other");
  m_Dialog.set_authors(list_authors);

  m_Dialog.signal_response().connect(
    sigc::mem_fun(*this, &amp;ExampleWindow::on_about_dialog_response) );

  show_all_children();

  // The widget must be realized and mapped before grab_focus() is called.
  // That's why it's called after show_all_children().
  m_Button.grab_focus();
}

ExampleWindow::~ExampleWindow()
{

}

void ExampleWindow::on_about_dialog_response(int response_id)
{
  std::cout &lt;&lt; response_id
    &lt;&lt; ", close=" &lt;&lt; Gtk::RESPONSE_CLOSE
    &lt;&lt; ", cancel=" &lt;&lt; Gtk::RESPONSE_CANCEL
    &lt;&lt; ", delete_event=" &lt;&lt; Gtk::RESPONSE_DELETE_EVENT
    &lt;&lt; std::endl;

  switch (response_id)
  {
  case Gtk::RESPONSE_CLOSE:
  case Gtk::RESPONSE_CANCEL:
  case Gtk::RESPONSE_DELETE_EVENT:
    m_Dialog.hide();
    break;
  default:
    std::cout &lt;&lt; "Unexpected response!" &lt;&lt; std::endl;
    break;
  }
}

void ExampleWindow::on_button_clicked()
{
  m_Dialog.show();

  //Bring it to the front, in case it was already shown:
  m_Dialog.present();
}
</programlisting>
<para lang="en">File: <filename>aboutdialog.gresource.xml</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
&lt;?xml version="1.0" encoding="UTF-8"?&gt;
&lt;gresources&gt;
  &lt;gresource prefix="/about"&gt;
    &lt;file&gt;gtkmm_logo.gif&lt;/file&gt;
  &lt;/gresource&gt;
&lt;/gresources&gt;
</programlisting>
<!-- end inserted example code -->
</sect2>

</sect1>

</chapter>

<chapter id="chapter-drawingarea">
  <title>L'élément graphique zone de dessin</title>
  <para lang="en">
    The <classname>DrawingArea</classname> widget is a blank window that gives
    you the freedom to create any graphic you desire. Along with that freedom
    comes the responsibility to handle draw signals on the widget. When a
    widget is first shown, or when it is covered and then uncovered again it
    needs to redraw itself. Most widgets have code to do this, but the
    DrawingArea does not, allowing you to write your own draw signal
    handler to determine how the contents of the widget will be drawn. This is
    most often done by overriding the virtual
    <methodname>on_draw()</methodname> member function.
  </para>

  <para lang="en">
      GTK+ uses the <ulink url="http://cairographics.org">Cairo</ulink> drawing API.
      With <application>gtkmm</application>, you may use the <ulink url="http://www.cairographics.org/cairomm/">cairomm</ulink> C++ API for cairo.
  </para>

  <para>Avec Cairo, vous pouvez tracer des figures très sophistiquées, mais les fonctions membres pour réaliser cela sont tout à fait simples. Cairo fournit des fonctions membres pour tracer des lignes droites, des lignes courbes et des arcs (y compris des cercles). Ces figures de base peuvent être combinées pour créer des formes complexes et des régions qui peuvent être remplies par des couleurs unies, des dégradés, des motifs et autres choses. En plus, Cairo peut effectuer des transformations complexes, des compositions d'images et effectuer des rendus de texte sans crénelage.</para>
  <note>
      <title>Cairo et Pango</title>
      <para>Même si Cairo peut afficher du texte, il n'a pas été conçu pour être un remplaçant de Pango. Pango est un meilleur choix si vous devez exécuter des rendus de texte complexes comme des textes enveloppants ou inscrits dans une ellipse. L'écriture avec Cairo doit être réservée à des textes intégrés dans un graphique.</para>
  </note>
  <para>Dans ce paragraphe du tutoriel, nous voyons le modèle du tracé de base Cairo ; nous décrivons chacun des éléments de tracé de base dans le détail (avec des exemples) et ensuite nous présentons une application simple utilisant Cairo pour dessiner un élément graphique d'horloge analogique.</para>
  <sect1 id="sec-cairo-drawing-model">
    <title>Le modèle de tracé Cairo</title>
    <para>Le concept de base du tracé dans Cairo consiste à définir des chemins « invisibles », puis à les tracer ou les remplir pour les rendre visibles.</para>
    <para lang="en">
        To do any drawing in <application>gtkmm</application> with Cairo, you must first create a
        <classname>Cairo::Context</classname> object. This class holds all of the graphics state parameters that
        describe how drawing is to be done. This includes information such as
        line width, color, the surface to draw to, and many other things. This
        allows the actual drawing functions to take fewer arguments to simplify
        the interface. In <application>gtkmm</application>, a <classname>Cairo::Context</classname> is
        created by calling the
        <methodname>Gdk::Window::create_cairo_context()</methodname> function.
        Since Cairo contexts are reference-counted objects, this function
        returns a <classname>Cairo::RefPtr&lt;Cairo::Context&gt;</classname>
        object.
    </para>
    <para>L'exemple ci-après montre comment définir un contexte Cairo avec une couleur de premier plan rouge et une épaisseur de trait de 2. Toute fonction de tracé se servant de ce contexte utilisera ces réglages.</para>
    <programlisting>Gtk::DrawingArea myArea;
Cairo::RefPtr&lt;Cairo::Context&gt; myContext = myArea.get_window()-&gt;create_cairo_context();
myContext-&gt;set_source_rgb(1.0, 0.0, 0.0);
myContext-&gt;set_line_width(2.0);</programlisting>
    <para>Chaque <classname>Cairo::Context</classname> est associé à une fenêtre <classname>Gdk::Window</classname> donnée ; ainsi, la première ligne de l'exemple ci-dessus crée un élément graphique <classname>Gtk::DrawingArea</classname> et la deuxième ligne utilise son objet <classname>Gdk::Window</classname> associé pour créer un objet <classname>Cairo::Context</classname>. Les deux dernières lignes modifient les caractéristiques graphiques du contexte.</para>
    <para>De nombreuses variables d'état graphique peuvent être définies pour un contexte Cairo. Les attributs les plus courants sont la couleur (avec <methodname>set_source_rgb()</methodname> ou <methodname>set_source_rgba()</methodname> pour des couleurs transparentes), l'épaisseur du trait (avec <methodname>set_line_width()</methodname>), le type de pointillé (avec <methodname>set_dash()</methodname>), les bouts de lignes (avec <methodname>set_line_cap()</methodname>), les jonctions de lignes (avec <methodname>set_line_join()</methodname>) et les styles de polices de caractères (avec <methodname>set_font_size()</methodname>, <methodname>set_font_face()</methodname> et autres). Il existe beaucoup d'autres réglages : les matrices de transformation, les règles de remplissage, les types  d'anti-crénelage, etc. Pour plus d'informations, consultez la documentation de l'API <ulink url="http://www.cairographics.org/cairomm/">cairomm</ulink>.</para>
    <para lang="en">
        The current state of a <classname>Cairo::Context</classname> can be
        saved to an internal stack of saved states and later be restored to the
        state it was in when you saved it. To do this, use the
        <methodname>save()</methodname>
        method and the <methodname>restore()</methodname> method. This can be
        useful if you need to temporarily change the line width and color (or
        any other graphics setting) in order to draw something and then return
        to the previous settings. In this situation, you could call
        <methodname>Cairo::Context::save()</methodname>, change the graphics
        settings, draw the lines, and then call
        <methodname>Cairo::Context::restore()</methodname> to restore the original
        graphics state. Multiple calls to <methodname>save()</methodname> and
        <methodname>restore()</methodname> can be nested; each call to
        <methodname>restore()</methodname> restores the state from the
        matching paired <methodname>save()</methodname>.
        <tip>
            <para lang="en">It is good practice to put all modifications to the graphics state
            between <methodname>save()</methodname>/<methodname>restore()</methodname>
            function calls. For example, if you have a function that takes a
            <classname>Cairo::Context</classname> reference as an argument, you
            might implement it as follows:
          </para>
          <programlisting lang="en">void doSomething(const Cairo::RefPtr&lt;Cairo::Context&gt;&amp; context, int x)
{
    context-&gt;save();
    // change graphics state
    // perform drawing operations
    context-&gt;restore();
}</programlisting>
        </tip>
    </para>
    <para lang="en">
        The virtual <methodname>on_draw()</methodname> method provides a
        Cairo context that you shall use for drawing in the
        <classname>Gtk::DrawingArea</classname> widget. It is not necessary to
        save and restore this Cairo context in <methodname>on_draw()</methodname>.
    </para>
  </sect1>
  <sect1 id="sec-cairo-drawing-lines">
    <title>Tracé de droites</title>
    <para lang="en">
        Now that we understand the basics of the Cairo graphics library, we're
        almost ready to start drawing. We'll start with the simplest of
        drawing elements: the straight line. But first you need to know a
        little bit about Cairo's coordinate system. The origin of the Cairo
        coordinate system is located in the upper-left corner of the window
        with positive x values to the right and positive y values going down.
        <tip>
            <para lang="en">Since the Cairo graphics library was written with support for
            multiple output targets (the X window system, PNG images, OpenGL,
            etc), there is a distinction between user-space and device-space
            coordinates. The mapping between these two coordinate systems
            defaults to one-to-one so that integer values map roughly to pixels
            on the screen, but this setting can be adjusted if desired.
            Sometimes it may be useful to scale the coordinates so that the
            full width and height of a window both range from 0 to 1 (the 'unit
            square') or some other mapping that works for your application.
            This can be done with the
            <methodname>Cairo::Context::scale()</methodname> function.</para>
        </tip>
    </para>

    <sect2 id="cairo-example-lines"><title>Exemple</title>
    <para>Dans cet exemple, nous allons écrire un programme <application>gtkmm</application> petit, mais pleinement fonctionnel, et tracer quelques lignes dans la fenêtre. Les lignes sont dessinées en créant un chemin, puis en le traçant. Un tracé est créé avec les fonctions <methodname>Cairo::Context::move_to()</methodname> et <methodname>Cairo::Context::line_to()</methodname>. La fonction <methodname>move_to()</methodname> est semblable à l'action de lever la pointe de votre crayon au dessus du papier et de la placer quelque part ailleurs — aucune ligne n'est tracée entre le point où vous étiez et celui où vous vous êtes déplacé. Pour tracer une ligne entre deux points, utilisez la fonction <methodname>line_to()</methodname>.</para>
    <para>Après avoir terminé la création de votre chemin, vous n'avez encore dessiné rien de visible. Pour rendre le chemin visible, il faut utiliser la fonction <methodname>stroke()</methodname> qui dessine le tracé actuel avec une ligne d'épaisseur et de style précisés dans l'objet <classname>Cairo::Context</classname>. Après le traçage, le chemin actuel est effacé ; vous pouvez donc en débuter un nouveau.</para>
        <tip>
            <para>Beaucoup de fonctions de dessin de Cairo disposent d'une variante <methodname>_preserve()</methodname>. Normalement, les fonctions de dessin telles que <methodname>clip()</methodname>, <methodname>fill()</methodname> ou <methodname>stroke()</methodname> effacent le chemin actuel. Si vous utilisez la variante <methodname>_preserve()</methodname>, le chemin actuel sera préservé de sorte que vous pouvez à nouveau l'utiliser avec une autre fonction de dessin.</para>
        </tip>

    <figure id="figure-drawingarea-lines">
      <title>Zone de dessin ‑ Lignes</title>
      <screenshot>
        <graphic format="PNG" fileref="figures/drawingarea_lines.png"/>
      </screenshot>
    </figure>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/drawingarea/simple?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>myarea.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLE_MYAREA_H
#define GTKMM_EXAMPLE_MYAREA_H

#include &lt;gtkmm/drawingarea.h&gt;

class MyArea : public Gtk::DrawingArea
{
public:
  MyArea();
  virtual ~MyArea();

protected:
  //Override default signal handler:
  bool on_draw(const Cairo::RefPtr&lt;Cairo::Context&gt;&amp; cr) override;
};

#endif // GTKMM_EXAMPLE_MYAREA_H
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "myarea.h"
#include &lt;gtkmm/application.h&gt;
#include &lt;gtkmm/window.h&gt;

int main(int argc, char** argv)
{
   auto app = Gtk::Application::create(argc, argv, "org.gtkmm.example");

   Gtk::Window win;
   win.set_title("DrawingArea");

   MyArea area;
   win.add(area);
   area.show();

   return app-&gt;run(win);
}
</programlisting>
<para lang="en">File: <filename>myarea.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "myarea.h"
#include &lt;cairomm/context.h&gt;

MyArea::MyArea()
{
}

MyArea::~MyArea()
{
}

bool MyArea::on_draw(const Cairo::RefPtr&lt;Cairo::Context&gt;&amp; cr)
{
  Gtk::Allocation allocation = get_allocation();
  const int width = allocation.get_width();
  const int height = allocation.get_height();

  // coordinates for the center of the window
  int xc, yc;
  xc = width / 2;
  yc = height / 2;

  cr-&gt;set_line_width(10.0);

  // draw red lines out from the center of the window
  cr-&gt;set_source_rgb(0.8, 0.0, 0.0);
  cr-&gt;move_to(0, 0);
  cr-&gt;line_to(xc, yc);
  cr-&gt;line_to(0, height);
  cr-&gt;move_to(xc, yc);
  cr-&gt;line_to(width, yc);
  cr-&gt;stroke();

  return true;
}
</programlisting>
<!-- end inserted example code -->

    <para lang="en">
        This program contains a single class, <classname>MyArea</classname>,
        which is a subclass of <classname>Gtk::DrawingArea</classname> and
        contains an <methodname>on_draw()</methodname> member function.
        This function is called whenever the image in the drawing area needs to
        be redrawn. It is passed a <classname>Cairo::RefPtr</classname>
        pointer to a <classname>Cairo::Context</classname> that we use
        for the drawing.
        The actual drawing code sets the color we want to use for drawing by
        using <methodname>set_source_rgb()</methodname> which takes arguments
        defining the Red, Green, and Blue components of the desired color
        (valid values are between 0 and 1). After setting the color, we
        created a new path using the functions <methodname>move_to()</methodname>
        and <methodname>line_to()</methodname>, and then stroked this path with
        <methodname>stroke()</methodname>.
    </para>
    <tip>
        <title>Tracé en coordonnées relatives</title>
        <para>Dans l'exemple ci-dessus nous avons tout tracé en utilisant des coordonnées absolues. Nous pouvons également tracer en coordonnées relatives. Pour une droite, on utilise la fonction <methodname>Cairo::Context::rel_line_to()</methodname>.</para>
    </tip>
    </sect2>
    <sect2 id="cairo-line-styles">
        <title>Styles de trait</title>
        <para>En plus du tracé élémentaire de droites, vous pouvez personnaliser un certain nombre de choses dans les tracés de lignes. Nous avons déjà vu des exemples de paramétrage de couleur et d'épaisseur de trait, mais il en existe bien d'autres.</para>
        <para>Si vous avez tiré une série de traits formant un chemin, vous pouvez vouloir les raccorder d'une certaine façon. Cairo offre trois façons différentes de raccorder les lignes entre elles : l'onglet, le biseau et l'arrondi. Voyez-les ci-dessous :</para>
        <figure id="figure-cairo-joins">
            <title>Différents types de raccord dans Cairo</title>
            <screenshot>
                <graphic format="PNG" fileref="figures/cairo_joins.png"/>
            </screenshot>
        </figure>
        <para>Le type de raccord est défini avec la fonction <methodname>Cairo::Context::set_line_join()</methodname>.</para>
        <para>Les fins de ligne peuvent avoir différents styles également. Le style par défaut est de débuter et arrêter la ligne exactement aux points de définition. On nomme cela la coupe droite. Les autres options sont l'arrondi (utilise une terminaison en demi-cercle, le centre du demi-cercle étant au point terminal de la ligne) ou le carré (utilise une terminaison carrée diagonale, le centre du carré étant au point terminal de la ligne). Ce paramétrage est défini avec la fonction <methodname>Cairo::Context::set_line_cap()</methodname>.</para>
        <para lang="en">
            There are other things you can customize as well, including
            creating dashed lines and other things. For more information, see
            the Cairo API documentation.
        </para>
    </sect2>
    <sect2 id="sec-cairo-thin-lines">
      <title lang="en">Drawing thin lines</title>
      <para lang="en">
        If you try to draw one pixel wide lines, you may notice that the line
        sometimes comes up blurred and wider than it ought to be.
        This happens because Cairo will try to draw from the selected position,
        to both sides (half to each), so if you're positioned right on the
        intersection of the pixels, and want a one pixel wide line, Cairo will try
        to use half of each adjacent pixel, which isn't possible (a pixel is the
        smallest unit possible). This happens when the width of the line is an
        odd number of pixels (not just one pixel).
      </para>
      <para lang="en">
        The trick is to position in the middle of the pixel where you want the
        line to be drawn, and thus guaranteeing you get the desired results.
        See <ulink url="http://cairographics.org/FAQ/#sharp_lines">Cairo FAQ</ulink>.
      </para>

      <figure id="figure-drawingarea-thin-lines">
        <title lang="en">Drawing Area - Thin Lines</title>
        <screenshot>
          <graphic format="PNG" fileref="figures/drawingarea_thin_lines.png"/>
        </screenshot>
      </figure>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/drawingarea/thin_lines?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>examplewindow.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLEWINDOW_H
#define GTKMM_EXAMPLEWINDOW_H

#include &lt;gtkmm/window.h&gt;
#include &lt;gtkmm/grid.h&gt;
#include &lt;gtkmm/checkbutton.h&gt;
#include "myarea.h"

class ExampleWindow : public Gtk::Window
{
public:
  ExampleWindow();
  virtual ~ExampleWindow();

protected:
  //Signal handlers:
  void on_button_toggled();

private:
  Gtk::Grid m_Container;
  MyArea m_Area_Lines;
  Gtk::CheckButton m_Button_FixLines;
};

#endif //GTKMM_EXAMPLEWINDOW_H
</programlisting>
<para lang="en">File: <filename>myarea.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLE_MYAREA_H
#define GTKMM_EXAMPLE_MYAREA_H

#include &lt;gtkmm/drawingarea.h&gt;

class MyArea : public Gtk::DrawingArea
{
public:
  MyArea();
  virtual ~MyArea();

  void fix_lines(bool fix = true);
  void force_redraw();

protected:
  //Override default signal handler:
  bool on_draw(const Cairo::RefPtr&lt;Cairo::Context&gt;&amp; cr) override;

private:
  double m_fix;
};

#endif // GTKMM_EXAMPLE_MYAREA_H
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;gtkmm/application.h&gt;

int main(int argc, char* argv[])
{
  auto app = Gtk::Application::create(argc, argv, "org.gtkmm.example");

  ExampleWindow window;

  //Shows the window and returns when it is closed.
  return app-&gt;run(window);
}
</programlisting>
<para lang="en">File: <filename>examplewindow.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"

ExampleWindow::ExampleWindow()
: m_Button_FixLines("Fix lines")
{
  set_title("Thin lines example");

  m_Container.set_orientation(Gtk::ORIENTATION_HORIZONTAL);

  m_Container.add(m_Area_Lines);
  m_Container.add(m_Button_FixLines);

  add(m_Container);

  m_Button_FixLines.signal_toggled().connect(
    sigc::mem_fun(*this, &amp;ExampleWindow::on_button_toggled));

  // Synchonize the drawing in m_Area_Lines with the state of the toggle button.
  on_button_toggled();

  show_all_children();
}

ExampleWindow::~ExampleWindow()
{
}

void ExampleWindow::on_button_toggled()
{
  m_Area_Lines.fix_lines(m_Button_FixLines.get_active());
}
</programlisting>
<para lang="en">File: <filename>myarea.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "myarea.h"

MyArea::MyArea()
: m_fix (0)
{
  set_size_request (200, 100);
}

MyArea::~MyArea()
{
}

bool MyArea::on_draw(const Cairo::RefPtr&lt;Cairo::Context&gt;&amp; cr)
{
  Gtk::Allocation allocation = get_allocation();
  const int width = allocation.get_width();
  const int height = allocation.get_height();

  cr-&gt;set_line_width(1.0);

  // draw one line, every two pixels
  // without the 'fix', you won't notice any space between the lines,
  // since each one will occupy two pixels (width)
  for (int i = 0; i &lt; width; i += 2)
  {
    cr-&gt;move_to(i + m_fix, 0);
    cr-&gt;line_to(i + m_fix, height);
  }

  cr-&gt;stroke();

  return true;
}

// Toogle between both values (0 or 0.5)
void MyArea::fix_lines(bool fix)
{
  // to get the width right, we have to draw in the middle of the pixel
  m_fix = fix ? 0.5 : 0.0;

  force_redraw();
}

// force the redraw of the image
void MyArea::force_redraw()
{
  auto win = get_window();
  if (win)
  {
    Gdk::Rectangle r(0, 0, get_allocation().get_width(), get_allocation().get_height());
    win-&gt;invalidate_rect(r, false);
  }
}
</programlisting>
<!-- end inserted example code -->
    </sect2>
  </sect1>

    <sect1 id="sec-cairo-curved-lines">
        <title>Tracé de courbes</title>
        <para>Outre la possibilité de tracer des droites, Cairo vous permet de tracer facilement des lignes courbes (techniquement une courbe de Bézier d'ordre 3) avec les fonctions <methodname>Cairo::Context::curve_to()</methodname> et <methodname>Cairo::Context::rel_curve_to()</methodname>. Ces fonctions prennent en paramètres les coordonnées des extrémités ainsi que celles de deux points de « contrôle ». Ce sera plus facile à expliquer sur un exemple, alors lançons-nous.</para>
        <sect2 id="cairo-example-curves">
            <title>Exemple</title>
            <para>Cette simple application trace une courbe avec Cairo et affiche les points de contrôle pour chaque extrémité de la courbe.</para>
        <figure id="figure-drawingarea-curve">
            <title>Zone de dessin ‑ Lignes</title>
            <screenshot>
                <graphic format="PNG" fileref="figures/drawingarea_curve.png"/>
            </screenshot>
        </figure>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/drawingarea/curve?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>myarea.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLE_MYAREA_H
#define GTKMM_EXAMPLE_MYAREA_H

#include &lt;gtkmm/drawingarea.h&gt;

class MyArea : public Gtk::DrawingArea
{
public:
  MyArea();
  virtual ~MyArea();

protected:
  //Override default signal handler:
  bool on_draw(const Cairo::RefPtr&lt;Cairo::Context&gt;&amp; cr) override;
};

#endif // GTKMM_EXAMPLE_MYAREA_H
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "myarea.h"
#include &lt;gtkmm/application.h&gt;
#include &lt;gtkmm/window.h&gt;

int main(int argc, char** argv)
{
   auto app = Gtk::Application::create(argc, argv, "org.gtkmm.example");

   Gtk::Window win;
   win.set_title("DrawingArea");

   MyArea area;
   win.add(area);
   area.show();

   return app-&gt;run(win);
}
</programlisting>
<para lang="en">File: <filename>myarea.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "myarea.h"
#include &lt;cairomm/context.h&gt;

MyArea::MyArea()
{
}

MyArea::~MyArea()
{
}

bool MyArea::on_draw(const Cairo::RefPtr&lt;Cairo::Context&gt;&amp; cr)
{
  Gtk::Allocation allocation = get_allocation();
  const int width = allocation.get_width();
  const int height = allocation.get_height();

  double x0=0.1, y0=0.5, // start point
         x1=0.4, y1=0.9,  // control point #1
         x2=0.6, y2=0.1,  // control point #2
         x3=0.9, y3=0.5;  // end point

  // scale to unit square (0 to 1 width and height)
  cr-&gt;scale(width, height);

  cr-&gt;set_line_width(0.05);
  // draw curve
  cr-&gt;move_to(x0, y0);
  cr-&gt;curve_to(x1, y1, x2, y2, x3, y3);
  cr-&gt;stroke();
  // show control points
  cr-&gt;set_source_rgba(1, 0.2, 0.2, 0.6);
  cr-&gt;move_to(x0, y0);
  cr-&gt;line_to (x1, y1);
  cr-&gt;move_to(x2, y2);
  cr-&gt;line_to (x3, y3);
  cr-&gt;stroke();

  return true;
}
</programlisting>
<!-- end inserted example code -->
        <para lang="en">
            The only difference between this example and the straight line
            example is in the <methodname>on_draw()</methodname> function,
            but there are a few new concepts and functions introduced here, so
            let's examine them briefly.
        </para>
        <para lang="en">
            We make a call to
            <methodname>Cairo::Context::scale()</methodname>, passing in the width
            and height of the drawing area. This scales the user-space
            coordinate system such that the width and height of the widget
            are both equal to 1.0 'units'. There's no particular reason to
            scale the coordinate system in this case, but sometimes it can make
            drawing operations easier.
        </para>
        <para lang="en">
            The call to <methodname>Cairo::Context::curve_to()</methodname> should
            be fairly self-explanatory. The first pair of coordinates define
            the control point for the beginning of the curve. The second set
            of coordinates define the control point for the end of the curve,
            and the last set of coordinates define the destination point. To
            make the concept of control points a bit easier to visualize, a
            line has been drawn from each control point to the end-point on the
            curve that it is associated with. Note that these control point
            lines are both translucent. This is achieved with a variant of
            <methodname>set_source_rgb()</methodname> called
            <methodname>set_source_rgba()</methodname>. This function takes a
            fourth argument specifying the alpha value of the color (valid
            values are between 0 and 1).
        </para>
        </sect2>
  </sect1>
  <sect1 id="sec-cairo-drawing-arcs">
      <title>Tracé des arcs et des cercles</title>
      <para lang="en">
          With Cairo, the same function is used to draw arcs, circles, or
          ellipses: <methodname>Cairo::Context::arc()</methodname>. This function
          takes five arguments. The first two are the coordinates of the
          center point of the arc, the third argument is the radius of the arc,
          and the final two arguments define the start and end angle of the
          arc. All angles are defined in radians, so drawing a circle is the
          same as drawing an arc from 0 to 2 * M_PI radians.
          An angle of 0 is in the direction of the positive X axis (in user-space). An
          angle of M_PI/2 radians (90 degrees) is in the direction of the positive Y axis
          (in user-space). Angles increase in the direction from the positive X axis
          toward the positive Y axis. So with the default transformation matrix, angles
          increase in a clockwise direction. (Remember that the positive Y axis
          points downwards.)
      </para>
      <para lang="en">
          To draw an ellipse, you can scale the current transformation matrix
          by different amounts in the X and Y directions. For example, to draw
          an ellipse with center at <varname>x</varname>, <varname>y</varname>
          and size <varname>width</varname>, <varname>height</varname>:

          <programlisting lang="en">context-&gt;save();
context-&gt;translate(x, y);
context-&gt;scale(width / 2.0, height / 2.0);
context-&gt;arc(0.0, 0.0, 1.0, 0.0, 2 * M_PI);
context-&gt;restore();</programlisting>
      </para>
      <sect2 id="cairo-example-arcs">
          <title>Exemple</title>
          <para>Voici un exemple de programme simple traçant un arc, un cercle et une ellipse sur une zone de dessin.</para>
          <figure id="figure-drawingarea-arc">
              <title>Zone de dessin ‑ Arcs</title>
              <screenshot>
                  <graphic format="PNG" fileref="figures/drawingarea_arcs.png"/>
              </screenshot>
          </figure>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/drawingarea/arcs?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>myarea.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLE_MYAREA_H
#define GTKMM_EXAMPLE_MYAREA_H

#include &lt;gtkmm/drawingarea.h&gt;

class MyArea : public Gtk::DrawingArea
{
public:
  MyArea();
  virtual ~MyArea();

protected:
  //Override default signal handler:
  bool on_draw(const Cairo::RefPtr&lt;Cairo::Context&gt;&amp; cr) override;
};

#endif // GTKMM_EXAMPLE_MYAREA_H
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "myarea.h"
#include &lt;gtkmm/application.h&gt;
#include &lt;gtkmm/window.h&gt;

int main(int argc, char** argv)
{
   auto app = Gtk::Application::create(argc, argv, "org.gtkmm.example");

   Gtk::Window win;
   win.set_title("DrawingArea");

   MyArea area;
   win.add(area);
   area.show();

   return app-&gt;run(win);
}
</programlisting>
<para lang="en">File: <filename>myarea.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "myarea.h"
#include &lt;cairomm/context.h&gt;
#include &lt;cmath&gt;

MyArea::MyArea()
{
}

MyArea::~MyArea()
{
}

bool MyArea::on_draw(const Cairo::RefPtr&lt;Cairo::Context&gt;&amp; cr)
{
  // This is where we draw on the window
  Gtk::Allocation allocation = get_allocation();
  const int width = allocation.get_width();
  const int height = allocation.get_height();
  const int lesser = MIN(width, height);

  // coordinates for the center of the window
  int xc, yc;
  xc = width / 2;
  yc = height / 2;

  cr-&gt;set_line_width(lesser * 0.02);  // outline thickness changes
                                      // with window size

  // first draw a simple unclosed arc
  cr-&gt;save();
  cr-&gt;arc(width / 3.0, height / 4.0, lesser / 4.0, -(M_PI / 5.0), M_PI);
  cr-&gt;close_path();   // line back to start point
  cr-&gt;set_source_rgb(0.0, 0.8, 0.0);
  cr-&gt;fill_preserve();
  cr-&gt;restore();  // back to opaque black
  cr-&gt;stroke();   // outline it

  // now draw a circle
  cr-&gt;save();
  cr-&gt;arc(xc, yc, lesser / 4.0, 0.0, 2.0 * M_PI); // full circle
  cr-&gt;set_source_rgba(0.0, 0.0, 0.8, 0.6);    // partially translucent
  cr-&gt;fill_preserve();
  cr-&gt;restore();  // back to opaque black
  cr-&gt;stroke();

  // and finally an ellipse
  double ex, ey, ew, eh;
  // center of ellipse
  ex = xc;
  ey = 3.0 * height / 4.0;
  // ellipse dimensions
  ew = 3.0 * width / 4.0;
  eh = height / 3.0;

  cr-&gt;save();

  cr-&gt;translate(ex, ey);  // make (ex, ey) == (0, 0)
  cr-&gt;scale(ew / 2.0, eh / 2.0);  // for width: ew / 2.0 == 1.0
                                  // for height: eh / 2.0 == 1.0

  cr-&gt;arc(0.0, 0.0, 1.0, 0.0, 2 * M_PI);  // 'circle' centered at (0, 0)
                                          // with 'radius' of 1.0

  cr-&gt;set_source_rgba(0.8, 0.0, 0.0, 0.7);
  cr-&gt;fill_preserve();
  cr-&gt;restore();  // back to opaque black
  cr-&gt;stroke();

  return true;
}
</programlisting>
<!-- end inserted example code -->

          <para lang="en">
              There are a couple of things to note about this example code.
              Again, the only real difference between this example and the
              previous ones is the <methodname>on_draw()</methodname>
              function, so we'll limit our focus to that function. In
              addition, the first part of the function is nearly identical to
              the previous examples, so we'll skip that portion.
          </para>
          <para>Notez que dans ce cas, nous avons pratiquement tout exprimé en termes de hauteur et de largeur de la fenêtre, y compris la largeur des lignes. En raison de cela, quand vous redimensionnez la fenêtre, tous les objets se mettent à l'échelle. Également, il y a trois parties concernant les tracés dans la fonction et chacune est entourée avec une paire <methodname>save()</methodname>/<methodname>restore()</methodname> pour revenir à un état bien défini après chaque tracé.</para>
          <para>La partie concernant le tracé de l'arc comporte une nouvelle fonction : <methodname>close_path()</methodname>. Cette fonction a pour effet de provoquer le tracé d'une droite entre le point de fin et de début du tracé. Il y a toutefois une différence significative entre l'appel de <methodname>close_path()</methodname> et le tracé à la main d'une ligne jusqu'au point de départ. Si vous utilisez <methodname>close_path()</methodname>, les lignes seront proprement jointes. Si vous utilisez <methodname>line_to()</methodname> à la place, les lignes se rejoindront, mais Cairo ne fera rien de spécial pour les joindre.</para>
          <note>
              <title>Tracé en sens inverse des aiguilles d'une montre</title>
              <para>La fonction <methodname>Cairo::Context::arc_negative()</methodname> est identique à <methodname>Cairo::Context::arc()</methodname> mais les angles tournent dans le sens opposé.</para>
          </note>

      </sect2>
  </sect1>
  <sect1 id="sec-drawing-text">
      <title>Tracé de textes</title>
      <sect2 id="drawing-text-pango">
          <title>Tracé de texte avec Pango</title>
          <para lang="en">
              Text is drawn via Pango Layouts. The easiest way to create a
              <classname>Pango::Layout</classname> is to use
              <methodname>Gtk::Widget::create_pango_layout()</methodname>.
              Once created, the layout can be manipulated in various ways,
              including changing the text, font, etc. Finally, the layout can
              be rendered using the
              <methodname>Pango::Layout::show_in_cairo_context()</methodname> method.
          </para>
      </sect2>
      <sect2 id="pango-text-example">
        <title>Exemple</title>
        <para lang="en">
           Here is an example of a program that draws some text, some of it
           upside-down. The Printing chapter contains another
           <link linkend="sec-printing-example">example</link> of drawing text.
        </para>
        <figure id="figure-drawingarea-pango-text">
            <title lang="en">Drawing Area - Text</title>
            <screenshot>
                <graphic format="PNG" fileref="figures/drawingarea_pango_text.png"/>
            </screenshot>
        </figure>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/drawingarea/pango_text?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>myarea.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLE_MYAREA_H
#define GTKMM_EXAMPLE_MYAREA_H

#include &lt;gtkmm/drawingarea.h&gt;

class MyArea : public Gtk::DrawingArea
{
public:
  MyArea();
  virtual ~MyArea();

protected:
  //Override default signal handler:
  bool on_draw(const Cairo::RefPtr&lt;Cairo::Context&gt;&amp; cr) override;

private:
  void draw_rectangle(const Cairo::RefPtr&lt;Cairo::Context&gt;&amp; cr, int width, int height);
  void draw_text(const Cairo::RefPtr&lt;Cairo::Context&gt;&amp; cr, int rectangle_width, int rectangle_height);

};

#endif // GTKMM_EXAMPLE_MYAREA_H
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "myarea.h"
#include &lt;gtkmm/application.h&gt;
#include &lt;gtkmm/window.h&gt;

int main(int argc, char* argv[])
{
  auto app = Gtk::Application::create(argc, argv, "org.gtkmm.example");

  Gtk::Window window;
  window.set_title("Drawing text example");

  MyArea area;
  window.add(area);
  area.show();

  return app-&gt;run(window);
}
</programlisting>
<para lang="en">File: <filename>myarea.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "myarea.h"

MyArea::MyArea()
{
}

MyArea::~MyArea()
{
}

bool MyArea::on_draw(const Cairo::RefPtr&lt;Cairo::Context&gt;&amp; cr)
{
  Gtk::Allocation allocation = get_allocation();
  const int width = allocation.get_width();
  const int height = allocation.get_height();

  const int rectangle_width = width;
  const int rectangle_height = height / 2;

  // Draw a black rectangle
  cr-&gt;set_source_rgb(0.0, 0.0, 0.0);
  draw_rectangle(cr, rectangle_width, rectangle_height);

  // and some white text
  cr-&gt;set_source_rgb(1.0, 1.0, 1.0);
  draw_text(cr, rectangle_width, rectangle_height);

  // flip the image vertically
  // see http://www.cairographics.org/documentation/cairomm/reference/classCairo_1_1Matrix.html
  // the -1 corresponds to the yy part (the flipping part)
  // the height part is a translation (we could have just called cr-&gt;translate(0, height) instead)
  // it's height and not height / 2, since we want this to be on the second part of our drawing
  // (otherwise, it would draw over the previous part)
  Cairo::Matrix matrix(1.0, 0.0, 0.0, -1.0, 0.0, height);

  // apply the matrix
  cr-&gt;transform(matrix);

  // white rectangle
  cr-&gt;set_source_rgb(1.0, 1.0, 1.0);
  draw_rectangle(cr, rectangle_width, rectangle_height);

  // black text
  cr-&gt;set_source_rgb(0.0, 0.0, 0.0);
  draw_text(cr, rectangle_width, rectangle_height);

  return true;
}

void MyArea::draw_rectangle(const Cairo::RefPtr&lt;Cairo::Context&gt;&amp; cr,
                            int width, int height)
{
  cr-&gt;rectangle(0, 0, width, height);
  cr-&gt;fill();
}

void MyArea::draw_text(const Cairo::RefPtr&lt;Cairo::Context&gt;&amp; cr,
                       int rectangle_width, int rectangle_height)
{
  // http://developer.gnome.org/pangomm/unstable/classPango_1_1FontDescription.html
  Pango::FontDescription font;

  font.set_family("Monospace");
  font.set_weight(Pango::WEIGHT_BOLD);

  // http://developer.gnome.org/pangomm/unstable/classPango_1_1Layout.html
  auto layout = create_pango_layout("Hi there!");

  layout-&gt;set_font_description(font);

  int text_width;
  int text_height;

  //get the text dimensions (it updates the variables -- by reference)
  layout-&gt;get_pixel_size(text_width, text_height);

  // Position the text in the middle
  cr-&gt;move_to((rectangle_width-text_width)/2, (rectangle_height-text_height)/2);

  layout-&gt;show_in_cairo_context(cr);
}
</programlisting>
<!-- end inserted example code -->
      </sect2>

      <!--
      <sect2 id="drawing-text-cairo">
          <title>Drawing Text with Cairo</title>
          <warning>TODO: Add Cairo content.</warning>
      </sect2>
      -->
  </sect1>
  <sect1 id="sec-draw-images">
      <title>Affichage d'images</title>
          <para lang="en">
              There is a method for drawing from a
              <classname>Gdk::Pixbuf</classname> to a <classname>Cairo::Context</classname>.
              A <classname>Gdk::Pixbuf</classname> buffer is a useful wrapper
              around a collection of pixels, which can be read from files, and
              manipulated in various ways.
          </para>
          <para lang="en">
              Probably the most common way of creating
              <classname>Gdk::Pixbuf</classname>s is to use
              <methodname>Gdk::Pixbuf::create_from_file()</methodname> or
              <methodname>Gdk::Pixbuf::create_from_resource()</methodname>,
              which can read an image file, such as a png file into a pixbuf
              ready for rendering.
          </para>
          <para lang="en">
              The <classname>Gdk::Pixbuf</classname> can be rendered by setting
              it as the source pattern of the Cairo context with
              <methodname>Gdk::Cairo::set_source_pixbuf()</methodname>.
              Then draw the image with either <methodname>Cairo::Context::paint()</methodname>
              (to draw the whole image), or <methodname>Cairo::Context::rectangle()</methodname>
              and <methodname>Cairo::Context::fill()</methodname> (to fill the
              specified rectangle). <methodname>set_source_pixbuf()</methodname>
              is not a member of <classname>Cairo::Context</classname>. It takes
              a <classname>Cairo::Context</classname> as its first parameter.
          </para>
          <para lang="en">
              Here is a small bit of code to tie it all together: (Note that
              usually you wouldn't load the image every time in the draw
              signal handler! It's just shown here to keep it all together.)
          </para>
          <programlisting lang="en">bool MyArea::on_draw(const Cairo::RefPtr&lt;Cairo::Context&gt;&amp; cr)
{
  Glib::RefPtr&lt;Gdk::Pixbuf&gt; image = Gdk::Pixbuf::create_from_file("myimage.png");
  // Draw the image at 110, 90, except for the outermost 10 pixels.
  Gdk::Cairo::set_source_pixbuf(cr, image, 100, 80);
  cr-&gt;rectangle(110, 90, image-&gt;get_width()-20, image-&gt;get_height()-20);
  cr-&gt;fill();
  return true;
}</programlisting>
        <sect2 id="cairo-example-image">
            <title>Exemple</title>
            <para lang="en">
                Here is an example of a simple program that draws an image.
                The program loads the image from a resource file. See the <link linkend="sec-gio-resource">Gio::Resource and glib-compile-resources</link>
                section. Use <application>glib-compile-resources</application> to compile
                the resources into a C source file that can be compiled and
                linked with the C++ code. E.g.
                <screen lang="en">$ glib-compile-resources --target=resources.c --generate-source image.gresource.xml</screen>
            </para>
        <figure id="figure-drawingarea-image">
            <title lang="en">Drawing Area - Image</title>
            <screenshot>
                <graphic format="PNG" fileref="figures/drawingarea_image.png"/>
            </screenshot>
        </figure>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/drawingarea/image?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>myarea.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLE_MYAREA_H
#define GTKMM_EXAMPLE_MYAREA_H

#include &lt;gtkmm/drawingarea.h&gt;
#include &lt;gdkmm/pixbuf.h&gt;

class MyArea : public Gtk::DrawingArea
{
public:
  MyArea();
  virtual ~MyArea();

protected:
  //Override default signal handler:
  bool on_draw(const Cairo::RefPtr&lt;Cairo::Context&gt;&amp; cr) override;

  Glib::RefPtr&lt;Gdk::Pixbuf&gt; m_image;
};

#endif // GTKMM_EXAMPLE_MYAREA_H
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "myarea.h"
#include &lt;gtkmm/application.h&gt;
#include &lt;gtkmm/window.h&gt;

int main(int argc, char** argv)
{
  auto app = Gtk::Application::create(argc, argv, "org.gtkmm.example");

  Gtk::Window win;
  win.set_title("DrawingArea");
  win.set_default_size(300, 200);

  MyArea area;
  win.add(area);
  area.show();

  return app-&gt;run(win);
}
</programlisting>
<para lang="en">File: <filename>myarea.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "myarea.h"
#include &lt;cairomm/context.h&gt;
#include &lt;giomm/resource.h&gt;
#include &lt;gdkmm/general.h&gt; // set_source_pixbuf()
#include &lt;glibmm/fileutils.h&gt;
#include &lt;iostream&gt;

MyArea::MyArea()
{
  try
  {
    // The fractal image has been created by the XaoS program.
    // http://xaos.sourceforge.net
    m_image = Gdk::Pixbuf::create_from_resource("/image/fractal_image.png");
  }
  catch(const Gio::ResourceError&amp; ex)
  {
    std::cerr &lt;&lt; "ResourceError: " &lt;&lt; ex.what() &lt;&lt; std::endl;
  }
  catch(const Gdk::PixbufError&amp; ex)
  {
    std::cerr &lt;&lt; "PixbufError: " &lt;&lt; ex.what() &lt;&lt; std::endl;
  }

  // Show at least a quarter of the image.
  if (m_image)
    set_size_request(m_image-&gt;get_width()/2, m_image-&gt;get_height()/2);
}

MyArea::~MyArea()
{
}

bool MyArea::on_draw(const Cairo::RefPtr&lt;Cairo::Context&gt;&amp; cr)
{
  if (!m_image)
    return false;

  Gtk::Allocation allocation = get_allocation();
  const int width = allocation.get_width();
  const int height = allocation.get_height();

  // Draw the image in the middle of the drawing area, or (if the image is
  // larger than the drawing area) draw the middle part of the image.
  Gdk::Cairo::set_source_pixbuf(cr, m_image,
    (width - m_image-&gt;get_width())/2, (height - m_image-&gt;get_height())/2);
  cr-&gt;paint();

  return true;
}
</programlisting>
<para lang="en">File: <filename>image.gresource.xml</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
&lt;?xml version="1.0" encoding="UTF-8"?&gt;
&lt;gresources&gt;
  &lt;gresource prefix="/image"&gt;
    &lt;file&gt;fractal_image.png&lt;/file&gt;
  &lt;/gresource&gt;
&lt;/gresources&gt;
</programlisting>
<!-- end inserted example code -->
        </sect2>
  </sect1>
  <!--
  <sect1 id="sec-drawing-fill">
      <title>Gradients and other fill techniques</title>
      <warning>TODO: Add content.</warning>
  </sect1>
  <sect1 id="sec-drawing-transformations">
      <title>Transformations with Cairo</title>
      <warning>TODO: Add content.</warning>
  </sect1>
  -->
  <sect1 id="sec-drawing-clock-example">
      <title>Exemple d'application : création d'un cadran d'horloge avec Cairo</title>
      <para>Maintenant que nous avons vu les fondements du tracé avec Cairo, rassemblons le tout et créons une application simple qui fasse effectivement quelque chose. L'exemple qui suit utilise Cairo pour créer un élément graphique <classname>Clock</classname> classique. L'horloge dispose d'aiguilles pour les secondes, les minutes et les heures ; elle se met à jour toutes les secondes.</para>
      <screenshot>
          <graphic format="PNG" fileref="figures/cairo_clock.png"/>
      </screenshot>
<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/drawingarea/clock?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>clock.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLE_CLOCK_H
#define GTKMM_EXAMPLE_CLOCK_H

#include &lt;gtkmm/drawingarea.h&gt;

class Clock : public Gtk::DrawingArea
{
public:
  Clock();
  virtual ~Clock();

protected:
  //Override default signal handler:
  bool on_draw(const Cairo::RefPtr&lt;Cairo::Context&gt;&amp; cr) override;

  bool on_timeout();

  double m_radius;
  double m_line_width;

};

#endif // GTKMM_EXAMPLE_CLOCK_H
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "clock.h"
#include &lt;gtkmm/application.h&gt;
#include &lt;gtkmm/window.h&gt;

int main(int argc, char** argv)
{
   auto app = Gtk::Application::create(argc, argv, "org.gtkmm.example");

   Gtk::Window win;
   win.set_title("Cairomm Clock");

   Clock c;
   win.add(c);
   c.show();

   return app-&gt;run(win);
}
</programlisting>
<para lang="en">File: <filename>clock.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include &lt;ctime&gt;
#include &lt;cmath&gt;
#include &lt;cairomm/context.h&gt;
#include &lt;glibmm/main.h&gt;
#include "clock.h"

Clock::Clock()
: m_radius(0.42), m_line_width(0.05)
{
  Glib::signal_timeout().connect( sigc::mem_fun(*this, &amp;Clock::on_timeout), 1000 );
}

Clock::~Clock()
{
}

bool Clock::on_draw(const Cairo::RefPtr&lt;Cairo::Context&gt;&amp; cr)
{
  Gtk::Allocation allocation = get_allocation();
  const int width = allocation.get_width();
  const int height = allocation.get_height();

  // scale to unit square and translate (0, 0) to be (0.5, 0.5), i.e.
  // the center of the window
  cr-&gt;scale(width, height);
  cr-&gt;translate(0.5, 0.5);
  cr-&gt;set_line_width(m_line_width);

  cr-&gt;save();
  cr-&gt;set_source_rgba(0.337, 0.612, 0.117, 0.9);   // green
  cr-&gt;paint();
  cr-&gt;restore();
  cr-&gt;arc(0, 0, m_radius, 0, 2 * M_PI);
  cr-&gt;save();
  cr-&gt;set_source_rgba(1.0, 1.0, 1.0, 0.8);
  cr-&gt;fill_preserve();
  cr-&gt;restore();
  cr-&gt;stroke_preserve();
  cr-&gt;clip();

  //clock ticks
  for (int i = 0; i &lt; 12; i++)
  {
    double inset = 0.05;

    cr-&gt;save();
    cr-&gt;set_line_cap(Cairo::LINE_CAP_ROUND);

    if(i % 3 != 0)
    {
      inset *= 0.8;
      cr-&gt;set_line_width(0.03);
    }

    cr-&gt;move_to(
      (m_radius - inset) * cos (i * M_PI / 6),
      (m_radius - inset) * sin (i * M_PI / 6));
    cr-&gt;line_to (
      m_radius * cos (i * M_PI / 6),
      m_radius * sin (i * M_PI / 6));
    cr-&gt;stroke();
    cr-&gt;restore(); /* stack-pen-size */
  }

  // store the current time
  time_t rawtime;
  time(&amp;rawtime);
  struct tm * timeinfo = localtime (&amp;rawtime);

  // compute the angles of the indicators of our clock
  double minutes = timeinfo-&gt;tm_min * M_PI / 30;
  double hours = timeinfo-&gt;tm_hour * M_PI / 6;
  double seconds= timeinfo-&gt;tm_sec * M_PI / 30;

  cr-&gt;save();
  cr-&gt;set_line_cap(Cairo::LINE_CAP_ROUND);

  // draw the seconds hand
  cr-&gt;save();
  cr-&gt;set_line_width(m_line_width / 3);
  cr-&gt;set_source_rgba(0.7, 0.7, 0.7, 0.8); // gray
  cr-&gt;move_to(0, 0);
  cr-&gt;line_to(sin(seconds) * (m_radius * 0.9),
    -cos(seconds) * (m_radius * 0.9));
  cr-&gt;stroke();
  cr-&gt;restore();

  // draw the minutes hand
  cr-&gt;set_source_rgba(0.117, 0.337, 0.612, 0.9);   // blue
  cr-&gt;move_to(0, 0);
  cr-&gt;line_to(sin(minutes + seconds / 60) * (m_radius * 0.8),
    -cos(minutes + seconds / 60) * (m_radius * 0.8));
  cr-&gt;stroke();

  // draw the hours hand
  cr-&gt;set_source_rgba(0.337, 0.612, 0.117, 0.9);   // green
  cr-&gt;move_to(0, 0);
  cr-&gt;line_to(sin(hours + minutes / 12.0) * (m_radius * 0.5),
    -cos(hours + minutes / 12.0) * (m_radius * 0.5));
  cr-&gt;stroke();
  cr-&gt;restore();

  // draw a little dot in the middle
  cr-&gt;arc(0, 0, m_line_width / 3.0, 0, 2 * M_PI);
  cr-&gt;fill();

  return true;
}


bool Clock::on_timeout()
{
    // force our program to redraw the entire clock.
    auto win = get_window();
    if (win)
    {
        Gdk::Rectangle r(0, 0, get_allocation().get_width(),
                get_allocation().get_height());
        win-&gt;invalidate_rect(r, false);
    }
    return true;
}
</programlisting>
<!-- end inserted example code -->
      <para lang="en">
          As before, almost all of the interesting stuff is done in the draw
          signal handler <methodname>on_draw()</methodname>. Before we dig
          into the draw signal handler, notice that the constructor for the
          <classname>Clock</classname> widget connects a handler function
          <methodname>on_timeout()</methodname> to a timer with a timeout
          period of 1000 milliseconds (1 second). This means that
          <methodname>on_timeout()</methodname> will get called once per
          second. The sole responsibility of this function is to invalidate
          the window so that <application>gtkmm</application> will be forced to redraw it.
      </para>
      <para lang="en">
          Now let's take a look at the code that performs the actual drawing.
          The first section of <methodname>on_draw()</methodname> should be
          pretty familiar by now. This example again scales the coordinate system
          to be a unit square so that it's easier to draw the clock as a
          percentage of window size so that it will automatically scale when
          the window size is adjusted. Furthermore, the coordinate system is
          scaled over and down so that the (0, 0) coordinate is in the very
          center of the window.
      </para>
      <para lang="en">
          The function <methodname>Cairo::Context::paint()</methodname> is used here
          to set the background color of the window. This function takes no
          arguments and fills the current surface (or the clipped portion of
          the surface) with the source color currently active. After setting
          the background color of the window, we draw a circle for the clock
          outline, fill it with white, and then stroke the outline in black.
          Notice that both of these actions use the
          <methodname>_preserve</methodname> variant to preserve the current path,
          and then this same path is clipped to make sure that our next lines
          don't go outside the outline of the clock.
      </para>
      <para>Après avoir tracé le pourtour, nous parcourons la circonférence du cadran et traçons des marques pour chaque heure, avec une marque plus importante pour midi, trois, six et neuf heures. Nous sommes maintenant prêts pour implémenter la fonctionnalité horloge de notre cadran : cela consiste à obtenir la valeur actuelle des heures, minutes et secondes et à tracer les aiguilles avec les angles adéquats.</para>
  </sect1>
</chapter>

<chapter id="chapter-draganddrop">
<title>Glisser-déposer</title>
<para><classname>Gtk::Widget</classname> dispose de plusieurs fonctions membres et signaux préfixés par « drag_ » qui sont utilisés pour le glisser-déposer.</para>
<sect1 id="sec-dnd-sources-destinations">
<title>Sources et destinations</title>
<para>Les objets sont glissés à partir de <literal>sources</literal> pour être déposés sur des <literal>destinations</literal>. Chaque source et chaque destination dispose d'informations à propos du format des données qu'elle peut recevoir ou envoyer, informations fournies par les éléments <classname>Gtk::TargetEntry</classname>. Une destination de dépôt n'accepte un élément glissé que s'ils partagent un élément <classname>Gtk::TargetEntry</classname> compatible. Les signaux appropriés sont alors émis, indiquant au gestionnaire de signaux le <classname>Gtk::TargetEntry</classname> qui a été utilisé.</para>
<para lang="en">
<classname>Gtk::TargetEntry</classname> objects contain this information:
<itemizedlist>
<listitem><para lang="en">target: A name, such as "STRING"</para></listitem>
<listitem><para lang="en">info: An identifier which will be sent to your signals to tell you which TargetEntry was used.</para></listitem>
<listitem><para lang="en">flags: Used only for drag and drop, this specifies whether the data may be dragged to other widgets and applications, or only to the same ones.</para></listitem>
</itemizedlist>
</para>

</sect1>

<sect1 id="sec-dnd-methods">
<title>Fonctions membres</title>
<para lang="en">
<classname>Widget</classname>s can be identified as sources or destinations
using these <classname>Gtk::Widget</classname> methods:
</para>
<programlisting lang="en">void drag_source_set(const std::vector&lt;Gtk::TargetEntry&gt;&amp; targets,
      Gdk::ModifierType start_button_mask, Gdk::DragAction actions);</programlisting>

<itemizedlist>
<listitem>
    <para lang="en">
        <literal>targets</literal> is a vector of
        <classname>Gtk::TargetEntry</classname> elements.
    </para>
</listitem>
<listitem>
    <para><literal>start_button_mask</literal> est une combinaison de valeurs liées avec l'opérateur binaire OR ; ces valeurs définissent quelle touche modificatrice ou quel bouton de souris doit être pressé pour démarrer le glisser.</para>
</listitem>
<listitem>
    <para><literal>actions</literal> est une combinaison de valeurs liées avec l'opérateur binaire OR ; elle précise les opérations de glisser-déposer possibles à partir de cette source — par exemple, copier, déplacer ou lier. L'utilisateur peut choisir le type d'opérations avec les touches modificatrices ; ainsi, <keycap>Maj</keycap> permet de transformer la « <literal>copie</literal> » en « <literal>déplacement</literal> » ; ce changement est indiqué par la modification de la forme du pointeur de souris.</para>
</listitem>
</itemizedlist>

<programlisting lang="en">void drag_dest_set(const std::vector&lt;Gtk::TargetEntry&gt;&amp; targets,
    Gtk::DestDefaults flags, Gdk::DragAction actions);</programlisting>

<itemizedlist>
<listitem>
    <para><literal>flags</literal> est une combinaison de valeurs liées par l'opérateur binaire OR ; cette combinaison indique comment l'élément graphique répond visuellement aux éléments du glisser-déposer.</para>
</listitem>
<listitem>
    <para><literal>actions</literal> indique les actions de glisser-déposer que cette destination peut accepter — voir la description plus haut.</para>
</listitem>
</itemizedlist>
</sect1>

<sect1 id="sec-dnd-signals">
<title>Signaux</title>
<para>Quand une destination a accepté un élément glissé, certains signaux vont être émis selon l'action choisie. Par exemple, l'utilisateur peut avoir maintenu enfoncée la touche <keycap>Maj</keycap> pour indiquer un <literal>déplacement</literal> plutôt qu'une <literal>copie</literal>. Souvenez-vous que l'utilisateur ne peut sélectionner que les actions définies dans vos appels à <methodname>drag_dest_set()</methodname> et <methodname>drag_source_set()</methodname>.</para>

<sect2 id="sec-dnd-signals-copy">
<title>Copie</title>
<para lang="en">
The source widget will emit these signals, in this order:
<itemizedlist>
<listitem><para lang="en"><literal>drag_begin</literal>: Provides DragContext.</para></listitem>
<listitem><para lang="en"><literal>drag_data_get</literal>: Provides <literal>info</literal> about the dragged data format, and a <literal>Gtk::SelectionData</literal> structure, in which you should put the requested data.</para></listitem>
<listitem><para lang="en"><literal>drag_end</literal>: Provides DragContext.</para></listitem>
</itemizedlist>
</para>
<para lang="en">
The destination widget will emit these signals, in this order:
<itemizedlist>
<listitem><para lang="en"><literal>drag_motion</literal>: Provides DragContext and coordinates.
  You can call the <methodname>drag_status()</methodname> method of the DragContext
  to indicate which action will be accepted.</para></listitem>
<listitem><para lang="en"><literal>drag_drop</literal>: Provides DragContext and coordinates.
  You can call <methodname>drag_get_data()</methodname>, which triggers the
  <literal>drag_data_get</literal> signal in the source widget, and then the
  <literal>drag_data_received</literal> signal in the destination widget.</para></listitem>
<listitem>
    <para lang="en">
        <literal>drag_data_received</literal>: Provides <literal>info</literal>
        about the dragged data format, and a
        <literal>Gtk::SelectionData</literal> structure which contains the
        dropped data. You should  call the <methodname>drag_finish()</methodname>
        method of the <literal>DragContext</literal> to indicate whether the
        operation was successful.
    </para>
</listitem>
</itemizedlist>
</para>

</sect2>

<sect2 id="dnd-signal-move">
<title>Déplacement</title>
<para lang="en">During a <literal>move</literal>, the source widget will also emit this signal:
<itemizedlist>
<listitem><para lang="en"><literal>drag_data_delete</literal>: Gives the source the opportunity to delete the original data if that's appropriate.</para></listitem>
</itemizedlist>
</para>
</sect2>

<!--
<sect2 id="dnd-signal-link">
<title>Link</title>
<para>TODO: Find an example or documentation.</para>
</sect2>
-->
</sect1>

<sect1 id="sec-dragcontext">
<title>DragContext</title>
<para>Les signaux de glisser-déposer fournissent un objet  DragContext contenant certaines informations à propos de l'opération de glisser-déposer ; ces informations peuvent être utilisées pour influer sur le processus. Par exemple, vous pouvez faire apparaître l'élément graphique source ou modifier l'icône de glisser-déposer avec <methodname>set_icon()</methodname>. Plus important, vous pouvez faire appel à la fonction membre <methodname>drag_finish()</methodname> dans le gestionnaire du signal <literal>drag_data_received</literal> pour savoir si le dépôt a réussi ou non.</para>
</sect1>

<sect1 id="sec-dnd-example">
<title>Exemple</title>
<para>Voici un exemple très simple montrant une opération de glisser-déposer avec <literal>copie</literal> :</para>

<figure id="figure-drag-and-drop">
  <title>Glisser-déposer</title>
  <screenshot>
    <graphic format="PNG" fileref="figures/drag_and_drop.png"/>
  </screenshot>
</figure>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/drag_and_drop?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>dndwindow.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLE_DNDWINDOW_H
#define GTKMM_EXAMPLE_DNDWINDOW_H

#include &lt;gtkmm/box.h&gt;
#include &lt;gtkmm/label.h&gt;
#include &lt;gtkmm/window.h&gt;
#include &lt;gtkmm/button.h&gt;

class DnDWindow : public Gtk::Window
{

public:
  DnDWindow();
  virtual ~DnDWindow();

protected:
  //Signal handlers:
  void on_button_drag_data_get(
          const Glib::RefPtr&lt;Gdk::DragContext&gt;&amp; context,
          Gtk::SelectionData&amp; selection_data, guint info, guint time);
  void on_label_drop_drag_data_received(
          const Glib::RefPtr&lt;Gdk::DragContext&gt;&amp; context, int x, int y,
          const Gtk::SelectionData&amp; selection_data, guint info, guint time);

  //Member widgets:
  Gtk::Box m_HBox;
  Gtk::Button m_Button_Drag;
  Gtk::Label m_Label_Drop;
};

#endif // GTKMM_EXAMPLE_DNDWINDOW_H
</programlisting>
<para lang="en">File: <filename>dndwindow.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "dndwindow.h"
#include &lt;iostream&gt;

DnDWindow::DnDWindow()
: m_Button_Drag("Drag Here\n"),
  m_Label_Drop("Drop here\n")
{
  set_title("DnD example");

  add(m_HBox);

  //Targets:
  std::vector&lt;Gtk::TargetEntry&gt; listTargets;
  listTargets.push_back( Gtk::TargetEntry("STRING") );
  listTargets.push_back( Gtk::TargetEntry("text/plain") );

  //Drag site:

  //Make m_Button_Drag a DnD drag source:
  m_Button_Drag.drag_source_set(listTargets);

  //Connect signals:
  m_Button_Drag.signal_drag_data_get().connect(sigc::mem_fun(*this,
              &amp;DnDWindow::on_button_drag_data_get));

  m_HBox.pack_start(m_Button_Drag);

  //Drop site:

  //Make m_Label_Drop a DnD drop destination:
  m_Label_Drop.drag_dest_set(listTargets);

  //Connect signals:
  m_Label_Drop.signal_drag_data_received().connect(sigc::mem_fun(*this,
              &amp;DnDWindow::on_label_drop_drag_data_received) );

  m_HBox.pack_start(m_Label_Drop);

  show_all();
}

DnDWindow::~DnDWindow()
{
}

void DnDWindow::on_button_drag_data_get(
        const Glib::RefPtr&lt;Gdk::DragContext&gt;&amp;,
        Gtk::SelectionData&amp; selection_data, guint, guint)
{
  selection_data.set(selection_data.get_target(), 8 /* 8 bits format */,
          (const guchar*)"I'm Data!",
          9 /* the length of I'm Data! in bytes */);
}

void DnDWindow::on_label_drop_drag_data_received(
        const Glib::RefPtr&lt;Gdk::DragContext&gt;&amp; context, int, int,
        const Gtk::SelectionData&amp; selection_data, guint, guint time)
{
  const int length = selection_data.get_length();
  if((length &gt;= 0) &amp;&amp; (selection_data.get_format() == 8))
  {
    std::cout &lt;&lt; "Received \"" &lt;&lt; selection_data.get_data_as_string()
        &lt;&lt; "\" in label " &lt;&lt; std::endl;
  }

  context-&gt;drag_finish(false, false, time);
}
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "dndwindow.h"
#include &lt;gtkmm/application.h&gt;

int main (int argc, char *argv[])
{
  auto app = Gtk::Application::create(argc, argv, "org.gtkmm.example");

  DnDWindow dndWindow;

  //Shows the window and returns when it is closed.
  return app-&gt;run(dndWindow);
}
</programlisting>
<!-- end inserted example code -->

<para lang="en">
There is a more complex example in examples/others/dnd.
</para>

</sect1>

</chapter>

<chapter id="chapter-clipboard">
<title>Le presse-papier</title>
<para lang="en">Simple text copy-paste functionality is provided for free by widgets such as
<classname>Gtk::Entry</classname> and <classname>Gtk::TextView</classname>,
but you might need special code to deal with your own data formats. For instance,
a drawing program would need special code to allow copy and paste within a view,
or between documents.</para>

<para lang="en">
You can usually pretend that <classname>Gtk::Clipboard</classname> is a singleton.
You can get the default clipboard instance with <methodname>Gtk::Clipboard::get()</methodname>.
This is probably the only clipboard you will ever need.
</para>

<para lang="en">
Your application doesn't need to wait for clipboard operations, particularly
between the time when the user chooses Copy and then later chooses Paste. Most
<classname>Gtk::Clipboard</classname> methods take
<classname>sigc::slot</classname>s which specify callback methods. When
<classname>Gtk::Clipboard</classname> is ready, it will call these methods,
either providing the requested data, or asking for data.
</para>

<para lang="en"><ulink url="http://developer.gnome.org/gtkmm/3.22/classGtk_1_1Clipboard.html">Reference</ulink></para>

<sect1 id="sec-clipboard-targets">
<title>Cibles</title>
<para>Diverses applications contiennent divers types de données ; elles peuvent mettre ces données à disposition sous des formats variés. <application>gtkmm</application> appelle ces types de données des « <literal>targets</literal> » (cibles).</para>

<para lang="en">
For instance, <application>gedit</application> can supply and receive the <literal>"UTF8_STRING"</literal>
target, so you can paste data into <application>gedit</application> from any application that supplies that target.
Or two different image editing applications might supply and receive a variety of image formats as targets.
As long as one application can receive one of the targets that the other supplies then you will be able to copy data from one to the other.
</para>

<para>Une cible peut se présenter sous des formats binaires divers. Ce chapitre, et ses exemples, supposent que les données sont du texte 8 bits. Cela vous permet d'utiliser un format XML pour les données du presse-papier. Toutefois ce format ne sera certainement pas approprié pour des données binaires comme les images. La classe <classname>Gtk::Clipboard</classname> autorise des sur-définitions permettant de spécifier le format de façon plus détaillée si nécessaire.</para>

<para lang="en">The <link linkend="chapter-draganddrop">Drag and Drop</link> API uses the same mechanism.
You should probably use the same data targets and formats for both Clipboard and Drag and Drop operations.</para>
</sect1>

<sect1 id="sec-clipboard-copy">
<title>Copie</title>
<para lang="en">
When the user asks to copy some data, you should tell the
<classname>Clipboard</classname> what targets are available, and provide the
callback methods that it can use to get the data. At this point you should
store a copy of the data, to be provided when the clipboard calls your callback
method in response to a paste.
</para>
<para>Par exemple,</para>
<programlisting lang="en">Glib::RefPtr&lt;Gtk::Clipboard&gt; refClipboard = Gtk::Clipboard::get();

//Targets:
std::vector&lt;Gtk::TargetEntry&gt; targets;
targets.push_back( Gtk::TargetEntry("example_custom_target") );
targets.push_back( Gtk::TargetEntry("UTF8_STRING") );

refClipboard-&gt;set( targets,
    sigc::mem_fun(*this, &amp;ExampleWindow::on_clipboard_get),
    sigc::mem_fun(*this, &amp;ExampleWindow::on_clipboard_clear) );</programlisting>

<para lang="en">Your callback will then provide the stored data when the user chooses to paste the data. For instance:
</para>
<programlisting lang="en">void ExampleWindow::on_clipboard_get(
    Gtk::SelectionData&amp; selection_data, guint /* info */)
{
  const std::string target = selection_data.get_target();

  if(target == "example_custom_target")
    selection_data.set("example_custom_target", m_ClipboardStore);
}</programlisting>
<para>L'exemple « <literal>idéal</literal> » ci-après peut fournir plus d'une cible de presse-papier.</para>

<para>La fonction de rappel de nettoyage libère la mémoire utilisée par le stockage de vos données quand le presse-papier remplace ses données par d'autres.</para>

</sect1>

<sect1 id="sec-clipboard-paste">
<title>Coller</title>
<para>Quand l'utilisateur demande à coller des données à partir du <classname>Clipboard</classname>, vous devez demander un format défini et fournir une fonction de rappel qui est appelée avec les vraies données. Par exemple :</para>
<programlisting>refClipboard-&gt;request_contents("example_custom_target",
    sigc::mem_fun(*this, &amp;ExampleWindow::on_clipboard_received) );</programlisting>

<para>Voici un exemple de fonction de rappel :</para>
<programlisting>void ExampleWindow::on_clipboard_received(
    const Gtk::SelectionData&amp; selection_data)
{
  Glib::ustring clipboard_data = selection_data.get_data_as_string();
  // Faire quelque choses avec les données collées.
}</programlisting>

<sect2 id="dnd-discovering-targets">
<title>Détermination des cibles admissibles</title>
<para>Pour retrouver quelles sont les cibles actuellement admissibles dans <classname>Clipboard</classname> pour le collage, appelez la fonction membre <methodname>request_targets()</methodname> en indiquant une fonction membre à appeler avec l'information. Par exemple :</para>
<programlisting>refClipboard-&gt;request_targets( sigc::mem_fun(*this,
    &amp;ExampleWindow::on_clipboard_received_targets) );</programlisting>

<para lang="en">
In your callback, compare the vector of available targets with those that your application supports for pasting. You could enable or disable a Paste menu item, depending on whether pasting is currently possible. For instance:
</para>
<programlisting lang="en">void ExampleWindow::on_clipboard_received_targets(
  const std::vector&lt;Glib::ustring&gt;&amp; targets)
{
  const bool bPasteIsPossible =
    std::find(targets.begin(), targets.end(),
      example_target_custom) != targets.end();

  // Enable/Disable the Paste button appropriately:
  m_Button_Paste.set_sensitive(bPasteIsPossible);
}</programlisting>
</sect2>

</sect1>

<sect1 id="sec-clipboard-examples"><title>Exemples</title>

<sect2 id="sec-clipboard-example-simple"><title>Simple</title>
<para>Cet exemple permet le copier-coller de données propres à une application, avec une cible texte standard. Il est simple, mais il n'est pas idéal parce qu'il n'identifie pas les données <classname>Clipboard</classname> comme étant d'un type donné.</para>

<figure id="figure-clipboard-simple">
  <title>Presse-papier - Simple</title>
  <screenshot>
    <graphic format="PNG" fileref="figures/clipboard_simple.png"/>
  </screenshot>
</figure>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/clipboard/simple/?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>examplewindow.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLEWINDOW_H
#define GTKMM_EXAMPLEWINDOW_H

#include &lt;gtkmm.h&gt;

class ExampleWindow : public Gtk::Window
{
public:
  ExampleWindow();
  virtual ~ExampleWindow();

protected:
  //Signal handlers:
  void on_button_copy();
  void on_button_paste();
  void on_clipboard_text_received(const Glib::ustring&amp; text);

  //Child widgets:
  Gtk::Box m_VBox;

  Gtk::Label m_Label;

  Gtk::Grid m_Grid;
  Gtk::ToggleButton m_ButtonA1, m_ButtonA2, m_ButtonB1, m_ButtonB2;

  Gtk::ButtonBox m_ButtonBox;
  Gtk::Button m_Button_Copy, m_Button_Paste;
};

#endif //GTKMM_EXAMPLEWINDOW_H
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;gtkmm/application.h&gt;

int main(int argc, char *argv[])
{
  //APPLICATION_NON_UNIQUE because it shall be possible to run several
  //instances of this application simultaneously.
  auto app = Gtk::Application::create(
    argc, argv, "org.gtkmm.example", Gio::APPLICATION_NON_UNIQUE);

  ExampleWindow window;

  //Shows the window and returns when it is closed.
  return app-&gt;run(window);
}
</programlisting>
<para lang="en">File: <filename>examplewindow.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"

ExampleWindow::ExampleWindow()
: m_VBox(Gtk::ORIENTATION_VERTICAL),
  m_Label("Select cells in the grid, click Copy, then open a second "
        "instance of this example to try pasting the copied data."),
  m_ButtonA1("A1"), m_ButtonA2("A2"), m_ButtonB1("B1"), m_ButtonB2("B2"),
  m_Button_Copy("_Copy", /* mnemonic= */ true), m_Button_Paste("_Paste", true)
{
  set_title("Gtk::Clipboard example");
  set_border_width(12);

  add(m_VBox);

  m_VBox.pack_start(m_Label, Gtk::PACK_SHRINK);

  //Fill Grid:
  m_VBox.pack_start(m_Grid);
  m_Grid.set_row_homogeneous(true);
  m_Grid.set_column_homogeneous(true);
  m_Grid.attach(m_ButtonA1, 0, 0, 1, 1);
  m_Grid.attach(m_ButtonA2, 1, 0, 1, 1);
  m_Grid.attach(m_ButtonB1, 0, 1, 1, 1);
  m_Grid.attach(m_ButtonB2, 1, 1, 1, 1);

  //Add ButtonBox to bottom:
  m_VBox.pack_start(m_ButtonBox, Gtk::PACK_SHRINK);
  m_VBox.set_spacing(6);

  //Fill ButtonBox:
  m_ButtonBox.set_layout(Gtk::BUTTONBOX_END);
  m_ButtonBox.pack_start(m_Button_Copy, Gtk::PACK_SHRINK);
  m_Button_Copy.signal_clicked().connect(sigc::mem_fun(*this,
              &amp;ExampleWindow::on_button_copy) );
  m_ButtonBox.pack_start(m_Button_Paste, Gtk::PACK_SHRINK);
  m_Button_Paste.signal_clicked().connect(sigc::mem_fun(*this,
              &amp;ExampleWindow::on_button_paste) );

  show_all_children();
}

ExampleWindow::~ExampleWindow()
{
}

void ExampleWindow::on_button_copy()
{
  //Build a string representation of the stuff to be copied:
  //Ideally you would use XML, with an XML parser here:
  Glib::ustring strData;
  strData += m_ButtonA1.get_active() ? "1" : "0";
  strData += m_ButtonA2.get_active() ? "1" : "0";
  strData += m_ButtonB1.get_active() ? "1" : "0";
  strData += m_ButtonB2.get_active() ? "1" : "0";

  auto refClipboard = Gtk::Clipboard::get();
  refClipboard-&gt;set_text(strData);
}

void ExampleWindow::on_button_paste()
{
  //Tell the clipboard to call our method when it is ready:
  auto refClipboard = Gtk::Clipboard::get();
  refClipboard-&gt;request_text(sigc::mem_fun(*this,
              &amp;ExampleWindow::on_clipboard_text_received) );
}

void ExampleWindow::on_clipboard_text_received(const Glib::ustring&amp; text)
{
  //See comment in on_button_copy() about this silly clipboard format.
  if(text.size() &gt;= 4)
  {
    m_ButtonA1.set_active( text[0] == '1' );
    m_ButtonA2.set_active( text[1] == '1' );
    m_ButtonB1.set_active( text[2] == '1' );
    m_ButtonB2.set_active( text[3] == '1' );
  }
}
</programlisting>
<!-- end inserted example code -->

</sect2>

<sect2 id="sec-clipboard-example-ideal"><title>Idéal</title>
<para lang="en">This is like the simple example, but it
<orderedlist>
<listitem><simpara lang="en">Defines a custom clipboard target, though the format of that target is still text.</simpara></listitem>
<listitem><simpara lang="en">It supports pasting of 2 targets - both the custom one and a text one that creates an arbitrary text representation of the custom data.</simpara></listitem>
<listitem><simpara lang="en">It uses <methodname>request_targets()</methodname> and the <literal>owner_change</literal> signal and disables the Paste button if it can't use anything on the clipboard.</simpara></listitem>
</orderedlist>
</para>

<figure id="figure-clipboard-ideal">
  <title>Presse-papier - Idéal</title>
  <screenshot>
    <graphic format="PNG" fileref="figures/clipboard_ideal.png"/>
  </screenshot>
</figure>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/clipboard/ideal/?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>examplewindow.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLEWINDOW_H
#define GTKMM_EXAMPLEWINDOW_H

#include &lt;gtkmm.h&gt;

class ExampleWindow : public Gtk::Window
{
public:
  ExampleWindow();
  virtual ~ExampleWindow();

protected:
  //Signal handlers:
  void on_button_copy();
  void on_button_paste();

  void on_clipboard_owner_change(GdkEventOwnerChange* event);
  void on_clipboard_get(Gtk::SelectionData&amp; selection_data, guint info);
  void on_clipboard_clear();

  void on_clipboard_received(const Gtk::SelectionData&amp; selection_data);
  void on_clipboard_received_targets(const std::vector&lt;Glib::ustring&gt;&amp; targets);

  void update_paste_status(); //Disable the paste button if there is nothing to paste.

  //Child widgets:
  Gtk::Box m_VBox;

  Gtk::Label m_Label;

  Gtk::Grid m_Grid;
  Gtk::ToggleButton m_ButtonA1, m_ButtonA2, m_ButtonB1, m_ButtonB2;

  Gtk::ButtonBox m_ButtonBox;
  Gtk::Button m_Button_Copy, m_Button_Paste;

  Glib::ustring m_ClipboardStore; //Keep copied stuff here, until it is pasted. This could be a big complex data structure.
};

#endif //GTKMM_EXAMPLEWINDOW_H
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;gtkmm/application.h&gt;

int main(int argc, char *argv[])
{
  //APPLICATION_NON_UNIQUE because it shall be possible to run several
  //instances of this application simultaneously.
  auto app = Gtk::Application::create(
    argc, argv, "org.gtkmm.example", Gio::APPLICATION_NON_UNIQUE);

  ExampleWindow window;

  //Shows the window and returns when it is closed.
  return app-&gt;run(window);
}
</programlisting>
<para lang="en">File: <filename>examplewindow.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;algorithm&gt;

namespace
{

//These should usually be MIME types.
const char example_target_custom[] = "gtkmmclipboardexample";
const char example_target_text[]   = "UTF8_STRING";

} // anonymous namespace


ExampleWindow::ExampleWindow()
: m_VBox(Gtk::ORIENTATION_VERTICAL),
  m_Label("Select cells in the grid, click Copy, then open a second instance "
          "of this example to try pasting the copied data.\nOr try pasting the "
          "text representation into gedit."),
  m_ButtonA1("A1"), m_ButtonA2("A2"), m_ButtonB1("B1"), m_ButtonB2("B2"),
  m_Button_Copy("_Copy", /* mnemonic= */ true), m_Button_Paste("_Paste", true)
{
  set_title("Gtk::Clipboard example");
  set_border_width(12);

  add(m_VBox);

  m_VBox.pack_start(m_Label, Gtk::PACK_SHRINK);

  //Fill Grid:
  m_VBox.pack_start(m_Grid);
  m_Grid.set_row_homogeneous(true);
  m_Grid.set_column_homogeneous(true);
  m_Grid.attach(m_ButtonA1, 0, 0, 1, 1);
  m_Grid.attach(m_ButtonA2, 1, 0, 1, 1);
  m_Grid.attach(m_ButtonB1, 0, 1, 1, 1);
  m_Grid.attach(m_ButtonB2, 1, 1, 1, 1);

  //Add ButtonBox to bottom:
  m_VBox.pack_start(m_ButtonBox, Gtk::PACK_SHRINK);
  m_VBox.set_spacing(6);

  //Fill ButtonBox:
  m_ButtonBox.set_layout(Gtk::BUTTONBOX_END);
  m_ButtonBox.pack_start(m_Button_Copy, Gtk::PACK_SHRINK);
  m_Button_Copy.signal_clicked().connect(sigc::mem_fun(*this,
              &amp;ExampleWindow::on_button_copy) );
  m_ButtonBox.pack_start(m_Button_Paste, Gtk::PACK_SHRINK);
  m_Button_Paste.signal_clicked().connect(sigc::mem_fun(*this,
              &amp;ExampleWindow::on_button_paste) );

  //Connect a signal handler that will be called when the contents of
  //the clipboard change.
  Gtk::Clipboard::get()-&gt;signal_owner_change().connect(sigc::mem_fun(*this,
              &amp;ExampleWindow::on_clipboard_owner_change) );

  show_all_children();

  update_paste_status();
}

ExampleWindow::~ExampleWindow()
{
}

void ExampleWindow::on_button_copy()
{
  //Build a string representation of the stuff to be copied:
  //Ideally you would use XML, with an XML parser here:
  Glib::ustring strData;
  strData += m_ButtonA1.get_active() ? "1" : "0";
  strData += m_ButtonA2.get_active() ? "1" : "0";
  strData += m_ButtonB1.get_active() ? "1" : "0";
  strData += m_ButtonB2.get_active() ? "1" : "0";

  auto refClipboard = Gtk::Clipboard::get();

  //Targets:
  std::vector&lt;Gtk::TargetEntry&gt; targets;

  targets.push_back( Gtk::TargetEntry(example_target_custom) );
  targets.push_back( Gtk::TargetEntry(example_target_text) );

  refClipboard-&gt;set(targets,
    sigc::mem_fun(*this, &amp;ExampleWindow::on_clipboard_get),
    sigc::mem_fun(*this, &amp;ExampleWindow::on_clipboard_clear) );

  //Store the copied data until it is pasted:
  //(Must be done after the call to refClipboard-&gt;set(), because that call
  //may trigger a call to on_clipboard_clear.)
  m_ClipboardStore = strData;

  update_paste_status();
}

void ExampleWindow::on_button_paste()
{
  //Tell the clipboard to call our method when it is ready:
  auto refClipboard = Gtk::Clipboard::get();

  refClipboard-&gt;request_contents(example_target_custom,
    sigc::mem_fun(*this, &amp;ExampleWindow::on_clipboard_received) );

  update_paste_status();
}

void ExampleWindow::on_clipboard_owner_change(GdkEventOwnerChange*)
{
  update_paste_status();
}

void ExampleWindow::on_clipboard_get(Gtk::SelectionData&amp; selection_data,
  guint /* info */)
{
  // info corresponds to the optional info parameter in Gtk::TargetEntry's
  // constructor. We don't use that, so we use selection_data's target instead.

  const std::string target = selection_data.get_target();

  if(target == example_target_custom)
  {
    // This set() override uses an 8-bit text format for the data.
    selection_data.set(example_target_custom, m_ClipboardStore);
  }
  else if(target == example_target_text)
  {
    //Build some arbitrary text representation of the data,
    //so that people see something when they paste into a text editor:
    Glib::ustring text_representation;

    text_representation += m_ButtonA1.get_active() ? "A1, " : "";
    text_representation += m_ButtonA2.get_active() ? "A2, " : "";
    text_representation += m_ButtonB1.get_active() ? "B1, " : "";
    text_representation += m_ButtonB2.get_active() ? "B2, " : "";

    selection_data.set_text(text_representation);
  }
  else
  {
    g_warning("ExampleWindow::on_clipboard_get(): "
            "Unexpected clipboard target format.");
  }
}

void ExampleWindow::on_clipboard_clear()
{
  //This isn't really necessary. I guess it might save memory.
  m_ClipboardStore.clear();
}

void ExampleWindow::on_clipboard_received(
        const Gtk::SelectionData&amp; selection_data)
{
  const std::string target = selection_data.get_target();

  //It should always be this, because that's what we asked for when calling
  //request_contents().
  if(target == example_target_custom)
  {
    Glib::ustring clipboard_data = selection_data.get_data_as_string();

    //See comment in on_button_copy() about this silly clipboard format.
    if(clipboard_data.size() &gt;= 4)
    {
      m_ButtonA1.set_active( clipboard_data[0] == '1' );
      m_ButtonA2.set_active( clipboard_data[1] == '1' );
      m_ButtonB1.set_active( clipboard_data[2] == '1' );
      m_ButtonB2.set_active( clipboard_data[3] == '1' );
    }
  }
}

void ExampleWindow::update_paste_status()
{
  //Disable the paste button if there is nothing to paste.

  auto refClipboard = Gtk::Clipboard::get();

  //Discover what targets are available:
  refClipboard-&gt;request_targets(sigc::mem_fun(*this,
              &amp;ExampleWindow::on_clipboard_received_targets) );
}

void ExampleWindow::on_clipboard_received_targets(
  const std::vector&lt;Glib::ustring&gt;&amp; targets)
{
  const bool bPasteIsPossible =
    std::find(targets.begin(), targets.end(),
      example_target_custom) != targets.end();

  // Enable/Disable the Paste button appropriately:
  m_Button_Paste.set_sensitive(bPasteIsPossible);
}
</programlisting>
<!-- end inserted example code -->

</sect2>

</sect1>


</chapter>

<chapter id="chapter-printing">
<title>Impression</title>

<para lang="en">
At the application development level, <application>gtkmm</application>'s printing API
provides dialogs that are consistent across applications and allows use of Cairo's common drawing API, with Pango-driven text rendering. In the implementation of this common API, platform-specific backends and printer-specific drivers are used.
</para>

<sect1 id="sec-printoperation">
<title>Objet PrintOperation</title>

<para>L'objet principal est <classname>Gtk::PrintOperation</classname>, alloué pour chaque opération d'impression. Pour gérer le tracé de la page, il faut se connecter à ses signaux, ou bien créer un objet dérivé et surdéfinir les gestionnaires de signaux virtuels fournis par défaut.  <classname>PrintOperation</classname> gère automatiquement tous les paramètres affectant la boucle d'impression.</para>

<sect2 id="sec-printoperation-signals">
<title>Signaux</title>

<para lang="en">
The <methodname>PrintOperation::run()</methodname> method starts the print loop,
during which various signals are emitted:

<itemizedlist>
  <listitem>
    <para lang="en">
      <literal>begin_print</literal>:
      You must handle this signal, because this is where you
      create and set up a <classname>Pango::Layout</classname> using the
      provided <classname>Gtk::PrintContext</classname>, and break up your
      printing output into pages.
    </para>
  </listitem>

  <listitem>
    <para lang="en">
      <literal>paginate</literal>: Pagination is potentially slow so if you
      need to monitor it you can call the
      <methodname>PrintOperation::set_show_progress()</methodname> method and
      handle this signal.
    </para>
  </listitem>

  <listitem>
    <para lang="en">
      For each page that needs to be rendered, the following signals
      are emitted:
      <itemizedlist>
        <listitem>
          <para lang="en">
            <literal>request_page_setup</literal>: Provides a
            <classname>PrintContext</classname>, page number and
            <classname>Gtk::PageSetup</classname>. Handle this signal if you
            need to modify page setup on a per-page basis.
          </para>
        </listitem>

        <listitem>
          <para lang="en">
            <literal>draw_page</literal>: You must handle this signal, which provides a
            <classname>PrintContext</classname> and a page number.
            The <classname>PrintContext</classname> should be used
            to create a <classname>Cairo::Context</classname> into which
            the provided page should be drawn. To render text, iterate over
            the <classname>Pango::Layout</classname> you created in the
            <literal>begin_print</literal> handler.
          </para>
        </listitem>
      </itemizedlist>
    </para>
  </listitem>

  <listitem>
    <para lang="en">
      <literal>end_print</literal>: A handler for it is a safe place to free
      any resources related to a <classname>PrintOperation</classname>.
      If you have your custom class that inherits from
      <classname>PrintOperation</classname>, it is naturally simpler to do it
      in the destructor.
    </para>
  </listitem>

  <listitem>
    <para lang="en">
      <literal>done</literal>: This signal is emitted when printing is finished, meaning when the
      print data is spooled. Note that the provided
      <literal>Gtk::PrintOperationResult</literal> may indicate that
      an error occurred. In any case you probably want to notify the user
      about the final status.
    </para>
  </listitem>

  <listitem>
    <para lang="en">
      <literal>status_changed</literal>: Emitted whenever a print job's
      status changes, until it is finished. Call the
      <methodname>PrintOperation::set_track_print_status()</methodname> method to
      monitor the job status after spooling. To see the status, use
      <methodname>get_status()</methodname> or
      <methodname>get_status_string()</methodname>.
    </para>
  </listitem>
</itemizedlist>

</para>

<para lang="en">
<ulink url="http://developer.gnome.org/gtkmm/3.22/classGtk_1_1PrintOperation.html">Reference</ulink>
</para>

</sect2>

</sect1>

<sect1 id="sec-page-setup">
<title>Mise en page</title>

<para>La classe <classname>PrintOperation</classname> dispose d'une fonction membre nommée <methodname>set_default_page_setup()</methodname> qui choisit par défaut une taille du papier, une orientation et des marges. Pour afficher la boîte de dialogue de mise en page dans l'application, servez-vous de la fonction membre <methodname>Gtk::run_page_setup_dialog()</methodname> qui renvoie un objet <classname>Gtk::PageSetup</classname> avec les réglages choisis. Utilisez cet objet pour mettre à jour un <classname>PrintOperation</classname> et avoir accès aux variables <classname>Gtk::PaperSize</classname>, <literal>Gtk::PageOrientation</literal> choisies ainsi qu'aux marges particulières à l'imprimante.</para>
<para>Enregistrez l'objet <classname>Gtk::PageSetup</classname> avec vos choix, ainsi vous pourrez l'utiliser à nouveau si la boîte de dialogue de mise en page est à nouveau affichée.</para>

<para lang="en">For instance,
<programlisting lang="en">
//Within a class that inherits from Gtk::Window and keeps m_refPageSetup and m_refSettings as members...
Glib::RefPtr&lt;Gtk::PageSetup&gt; new_page_setup = Gtk::run_page_setup_dialog(*this, m_refPageSetup, m_refSettings);
m_refPageSetup = new_page_setup;
</programlisting>
</para>

<para lang="en">
<ulink url="http://developer.gnome.org/gtkmm/3.22/classGtk_1_1PageSetup.html">Reference</ulink>
</para>

<para>Le système de coordonnées de Cairo, dans le gestionnaire de <literal>draw_page</literal>, est automatiquement tourné selon l'orientation de la page en cours. Il est normalement situé à l'intérieur des marges de l'imprimante, mais vous pouvez modifier ce réglage avec la fonction membre <methodname>PrintOperation::set_use_full_page()</methodname>. L'unité de mesure par défaut est le pixel du périphérique. Pour choisir d'autres unités, servez-vous de la fonction membre <methodname>PrintOperation::set_unit()</methodname>.</para>

</sect1>

<sect1 id="sec-printing-rendering-text">
<title>Rendu de texte</title>

<para>Le rendu du texte s'effectue avec Pango. L'objet <classname>Pango::Layout</classname> pour l'impression est créé en appelant la fonction membre <methodname>PrintContext::create_pango_layout()</methodname>. L'objet <classname>PrintContext</classname> indique également la métrique de la page par l'intermédiaire des fonctions <methodname>get_width()</methodname> et <methodname>get_height()</methodname>. Le nombre de pages peut être fixé à l'aide de <methodname>PrintOperation::set_n_pages()</methodname>. Pour effectuer le rendu effectif du texte Pango dans <literal>on_draw_page</literal>, obtenez un <classname>Cairo::Context</classname> avec la fonction membre <methodname>PrintContext::get_cairo_context()</methodname> et affichez les objets <classname>Pango::LayoutLine</classname> qui apparaissent dans le nombre de pages demandées.</para>

<para>Pour voir exactement comment réaliser ceci, consultez <link linkend="sec-printing-example-simple">cet exemple</link>.</para>

</sect1>

<sect1 id="sec-async-printing-ops">
<title>Opérations asynchrones</title>

<para>Par défaut, <methodname>PrintOperation::run()</methodname> rend la main quand l'opération d'impression est terminée. Si vous voulez lancer une opération d'impression non-bloquante, appelez <methodname>PrintOperation::set_allow_async()</methodname>. Notez que <methodname>set_allow_async()</methodname> n'est pas pris en charge sur toutes les plates-formes, bien que le signal <literal>done</literal> soit toujours émis.</para>

<para>Il se peut que la fonction membre <methodname>run()</methodname> renvoie <literal>PRINT_OPERATION_RESULT_IN_PROGRESS</literal>. Pour suivre l'état et gérer le résultat ou une erreur, vous devez implémenter des gestionnaires pour les signaux <literal>done</literal> et <literal>status_changed</literal> :</para>

<para lang="en">For instance,
<programlisting lang="en">
// in class ExampleWindow's method...
Glib::RefPtr&lt;PrintOperation&gt; op = PrintOperation::create();
// ...set up op...
op-&gt;signal_done().connect(sigc::bind(sigc::mem_fun(*this, &amp;ExampleWindow::on_printoperation_done), op));
// run the op
</programlisting>
</para>

<para lang="en">Second, check for an error and connect to the <literal>status_changed</literal> signal. For instance:
<programlisting lang="en">
void ExampleWindow::on_printoperation_done(Gtk::PrintOperationResult result, const Glib::RefPtr&lt;PrintOperation&gt;&amp; op)
{
  if (result == Gtk::PRINT_OPERATION_RESULT_ERROR)
    //notify user
  else if (result == Gtk::PRINT_OPERATION_RESULT_APPLY)
    //Update PrintSettings with the ones used in this PrintOperation

  if (! op-&gt;is_finished())
    op-&gt;signal_status_changed().connect(sigc::bind(sigc::mem_fun(*this, &amp;ExampleWindow::on_printoperation_status_changed), op));
}
</programlisting>
</para>

<para lang="en">Finally, check the status. For instance,
<programlisting lang="en">
void ExampleWindow::on_printoperation_status_changed(const Glib::RefPtr&lt;PrintFormOperation&gt;&amp; op)
{
  if (op-&gt;is_finished())
    //the print job is finished
  else
    //get the status with get_status() or get_status_string()

  //update UI
}
</programlisting>
</para>

</sect1>

<sect1 id="sec-printing-export-to-pdf">
<title>Exportation au format PDF</title>
<para lang="en">
The 'Print to file' option is available in the print dialog, without the need for extra implementation. However, it is sometimes useful to generate a pdf file directly from code. For instance,

<programlisting lang="en">
Glib::RefPtr&lt;Gtk::PrintOperation&gt; op = Gtk::PrintOperation::create();
// ...set up op...
op-&gt;set_export_filename("test.pdf");
Gtk::PrintOperationResult res = op-&gt;run(Gtk::PRINT_OPERATION_ACTION_EXPORT);
</programlisting>

</para>

</sect1>

<sect1 id="sec-extending-print-dialog">
<title>Extension de la boîte de dialogue d'impression</title>

<para lang="en">
You may add a custom tab to the print dialog:

<itemizedlist>
  <listitem>
    <para lang="en">
      Set the title of the tab via
      <methodname>PrintOperation::set_custom_tab_label()</methodname>,
      create a new widget and return it from the
      <literal>create_custom_widget</literal> signal handler. You'll probably
      want this to be a container widget, packed with some others.
    </para>
  </listitem>

  <listitem>
    <para lang="en">
      Get the data from the widgets in the
      <literal>custom_widget_apply</literal> signal handler.
    </para>
  </listitem>
</itemizedlist>
</para>

<para lang="en">
Although the <literal>custom_widget_apply</literal> signal provides the widget you
previously created, to simplify things you can keep the widgets you expect
to contain some user input as class members. For example, let's say you have
a <classname>Gtk::Entry</classname> called <literal>m_Entry</literal> as
a member of your <classname>CustomPrintOperation</classname> class:

<programlisting lang="en">
Gtk::Widget* CustomPrintOperation::on_create_custom_widget()
{
  set_custom_tab_label("My custom tab");

  Gtk::Box* hbox = new Gtk::Box(Gtk::ORIENTATION_HORIZONTAL, 8);
  hbox-&gt;set_border_width(6);

  Gtk::Label* label = Gtk::manage(new Gtk::Label("Enter some text: "));
  hbox-&gt;pack_start(*label, false, false);
  label-&gt;show();

  hbox-&gt;pack_start(m_Entry, false, false);
  m_Entry.show();

  return hbox;
}

void CustomPrintOperation::on_custom_widget_apply(Gtk::Widget* /* widget */)
{
  Glib::ustring user_input = m_Entry.get_text();
  //...
}
</programlisting>

</para>

<para>L'exemple dans le dossier <filename>examples/book/printing/advanced</filename> démontre cette façon d'opérer.</para>

</sect1>

<sect1 id="sec-printing-preview">
<title>Aperçu</title>

<para lang="en">
The native GTK+ print dialog has a preview button, but you may also start
a preview directly from an application:

<programlisting lang="en">
// in a class that inherits from Gtk::Window...
Glib::RefPtr&lt;PrintOperation&gt; op = PrintOperation::create();
// ...set up op...
op-&gt;run(Gtk::PRINT_OPERATION_ACTION_PREVIEW, *this);
</programlisting>
</para>

<para>Sous Unix, le gestionnaire d'aperçu par défaut utilise un programme externe de visualisation. Sous Windows, la boîte de dialogue d'aperçu native est affichée. Si nécessaire, vous pouvez surdéfinir ce comportement et fournir une boîte de dialogue d'aperçu personnalisée. Consultez l'exemple dans le dossier <filename>/examples/book/printing/advanced</filename>.</para>

</sect1>

<sect1 id="sec-printing-example">
<title>Exemple</title>

<sect2 id="sec-printing-example-simple">
<title>Simple</title>

<para>L'exemple suivant montre comment imprimer une saisie à partir d'une interface utilisateur. Il montre comment implémenter <literal>on_begin_print</literal> et <literal>on_draw_page</literal>, de même que suivre l'état de l'impression et mettre à jour les réglages.</para>

<figure id="figure-printing-simple">
  <title>Impression - Simple</title>
  <screenshot>
    <graphic format="PNG" fileref="figures/printing.png"/>
  </screenshot>
</figure>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/printing/simple/?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>examplewindow.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLEWINDOW_H
#define GTKMM_EXAMPLEWINDOW_H

// This file is part of the printing/simple and printing/advanced examples

#include &lt;gtkmm.h&gt;

class PrintFormOperation;

class ExampleWindow : public Gtk::Window
{
public:
  ExampleWindow(const Glib::RefPtr&lt;Gtk::Application&gt;&amp; app);
  virtual ~ExampleWindow();

protected:

  void build_main_menu(const Glib::RefPtr&lt;Gtk::Application&gt;&amp; app);

  void print_or_preview(Gtk::PrintOperationAction print_action);

  //PrintOperation signal handlers.
  //We handle these so can get necessary information to update the UI or print settings.
  //Our derived PrintOperation class also overrides some default signal handlers.
  void on_printoperation_status_changed();
  void on_printoperation_done(Gtk::PrintOperationResult result);

  //Action signal handlers:
  void on_menu_file_new();
  void on_menu_file_page_setup();
  void on_menu_file_print_preview();
  void on_menu_file_print();
  void on_menu_file_quit();

  //Printing-related objects:
  Glib::RefPtr&lt;Gtk::PageSetup&gt; m_refPageSetup;
  Glib::RefPtr&lt;Gtk::PrintSettings&gt; m_refSettings;
  Glib::RefPtr&lt;PrintFormOperation&gt; m_refPrintFormOperation;

  //Child widgets:
  Gtk::Box m_VBox;
  Gtk::Grid m_Grid;

  Gtk::Label m_NameLabel;
  Gtk::Entry m_NameEntry;

  Gtk::Label m_SurnameLabel;
  Gtk::Entry m_SurnameEntry;

  Gtk::Label m_CommentsLabel;
  Gtk::ScrolledWindow m_ScrolledWindow;
  Gtk::TextView m_TextView;

  Glib::RefPtr&lt;Gtk::TextBuffer&gt; m_refTextBuffer;

  unsigned m_ContextId;
  Gtk::Statusbar m_Statusbar;

  Glib::RefPtr&lt;Gtk::Builder&gt; m_refBuilder;
};

#endif //GTKMM_EXAMPLEWINDOW_H
</programlisting>
<para lang="en">File: <filename>printformoperation.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_PRINT_FORM_OPERATION_H
#define GTKMM_PRINT_FORM_OPERATION_H

#include &lt;gtkmm.h&gt;
#include &lt;pangomm.h&gt;
#include &lt;vector&gt;

//We derive our own class from PrintOperation,
//so we can put the actual print implementation here.
class PrintFormOperation : public Gtk::PrintOperation
{
 public:
  static Glib::RefPtr&lt;PrintFormOperation&gt; create();
  virtual ~PrintFormOperation();

  void set_name(const Glib::ustring&amp; name) { m_Name = name; }
  void set_comments(const Glib::ustring&amp; comments) { m_Comments = comments; }

 protected:
  PrintFormOperation();

  //PrintOperation default signal handler overrides:
  void on_begin_print(const Glib::RefPtr&lt;Gtk::PrintContext&gt;&amp; context) override;
  void on_draw_page(const Glib::RefPtr&lt;Gtk::PrintContext&gt;&amp; context, int page_nr) override;

  Glib::ustring m_Name;
  Glib::ustring m_Comments;
  Glib::RefPtr&lt;Pango::Layout&gt; m_refLayout;
  std::vector&lt;int&gt; m_PageBreaks; // line numbers where a page break occurs
};

#endif // GTKMM_PRINT_FORM_OPERATION_H
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;gtkmm/application.h&gt;

int main(int argc, char* argv[])
{
  auto app = Gtk::Application::create(argc, argv, "org.gtkmm.example");

  ExampleWindow window(app);

  // Shows the window and returns when it is closed.
  return app-&gt;run(window);
}
</programlisting>
<para lang="en">File: <filename>printformoperation.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "printformoperation.h"

PrintFormOperation::PrintFormOperation()
{
}

PrintFormOperation::~PrintFormOperation()
{
}

Glib::RefPtr&lt;PrintFormOperation&gt; PrintFormOperation::create()
{
  return Glib::RefPtr&lt;PrintFormOperation&gt;(new PrintFormOperation());
}

void PrintFormOperation::on_begin_print(
        const Glib::RefPtr&lt;Gtk::PrintContext&gt;&amp; print_context)
{
  //Create and set up a Pango layout for PrintData based on the passed
  //PrintContext: We then use this to calculate the number of pages needed, and
  //the lines that are on each page.
  m_refLayout = print_context-&gt;create_pango_layout();

  Pango::FontDescription font_desc("sans 12");
  m_refLayout-&gt;set_font_description(font_desc);

  const double width = print_context-&gt;get_width();
  const double height = print_context-&gt;get_height();

  m_refLayout-&gt;set_width(static_cast&lt;int&gt;(width * Pango::SCALE));

  //Set and mark up the text to print:
  Glib::ustring marked_up_form_text;
  marked_up_form_text += "&lt;b&gt;Name&lt;/b&gt;: " + m_Name + "\n\n";
  marked_up_form_text += "&lt;b&gt;Comments&lt;/b&gt;: " + m_Comments;

  m_refLayout-&gt;set_markup(marked_up_form_text);

  //Set the number of pages to print by determining the line numbers
  //where page breaks occur:
  const int line_count = m_refLayout-&gt;get_line_count();

  Glib::RefPtr&lt;Pango::LayoutLine&gt; layout_line;
  double page_height = 0;

  for (int line = 0; line &lt; line_count; ++line)
  {
    Pango::Rectangle ink_rect, logical_rect;

    layout_line = m_refLayout-&gt;get_line(line);
    layout_line-&gt;get_extents(ink_rect, logical_rect);

    const double line_height = logical_rect.get_height() / 1024.0;

    if (page_height + line_height &gt; height)
    {
      m_PageBreaks.push_back(line);
      page_height = 0;
    }

    page_height += line_height;
  }

  set_n_pages(m_PageBreaks.size() + 1);
}

void PrintFormOperation::on_draw_page(
        const Glib::RefPtr&lt;Gtk::PrintContext&gt;&amp; print_context, int page_nr)
{
  //Decide which lines we need to print in order to print the specified page:
  int start_page_line = 0;
  int end_page_line = 0;

  if(page_nr == 0)
  {
    start_page_line = 0;
  }
  else
  {
    start_page_line = m_PageBreaks[page_nr - 1];
  }

  if(page_nr &lt; static_cast&lt;int&gt;(m_PageBreaks.size()))
  {
    end_page_line = m_PageBreaks[page_nr];
  }
  else
  {
    end_page_line = m_refLayout-&gt;get_line_count();
  }

  //Get a Cairo Context, which is used as a drawing board:
  Cairo::RefPtr&lt;Cairo::Context&gt; cairo_ctx = print_context-&gt;get_cairo_context();

  //We'll use black letters:
  cairo_ctx-&gt;set_source_rgb(0, 0, 0);

  //Render Pango LayoutLines over the Cairo context:
  Pango::LayoutIter iter = m_refLayout-&gt;get_iter();

  double start_pos = 0;
  int line_index = 0;

  do
  {
    if(line_index &gt;= start_page_line)
    {
      auto layout_line = iter.get_line();
      Pango::Rectangle logical_rect = iter.get_line_logical_extents();
      int baseline = iter.get_baseline();

      if (line_index == start_page_line)
      {
        start_pos = logical_rect.get_y() / 1024.0;
      }

      cairo_ctx-&gt;move_to(logical_rect.get_x() / 1024.0,
        baseline / 1024.0 - start_pos);

      layout_line-&gt;show_in_cairo_context(cairo_ctx);
    }

    line_index++;
  }
  while(line_index &lt; end_page_line &amp;&amp; iter.next_line());
}

</programlisting>
<para lang="en">File: <filename>examplewindow.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include "printformoperation.h"
#include &lt;iostream&gt;

const Glib::ustring app_title = "gtkmm Printing Example";

ExampleWindow::ExampleWindow(const Glib::RefPtr&lt;Gtk::Application&gt;&amp; app)
: m_VBox(Gtk::ORIENTATION_VERTICAL),
  m_NameLabel("Name"),
  m_SurnameLabel("Surname"),
  m_CommentsLabel("Comments")
{
  m_refPageSetup = Gtk::PageSetup::create();
  m_refSettings = Gtk::PrintSettings::create();

  m_ContextId = m_Statusbar.get_context_id(app_title);

  set_title(app_title);
  set_default_size(400, 300);

  add(m_VBox);

  build_main_menu(app);

  m_VBox.pack_start(m_Grid);

  //Arrange the widgets inside the grid:
  m_Grid.set_row_spacing(5);
  m_Grid.set_column_spacing(5);
  m_Grid.attach(m_NameLabel, 0, 0, 1, 1);
  m_Grid.attach(m_NameEntry, 1, 0, 1, 1);

  m_Grid.attach(m_SurnameLabel, 0, 1, 1, 1);
  m_Grid.attach(m_SurnameEntry, 1, 1, 1, 1);

  //Add the TextView, inside a ScrolledWindow:
  m_ScrolledWindow.add(m_TextView);

  //Only show the scrollbars when they are necessary:
  m_ScrolledWindow.set_policy(Gtk::POLICY_AUTOMATIC, Gtk::POLICY_AUTOMATIC);

  m_Grid.attach(m_CommentsLabel, 0, 2, 1, 1);
  m_Grid.attach(m_ScrolledWindow, 1, 2, 1, 1);
  m_ScrolledWindow.set_hexpand(true);
  m_ScrolledWindow.set_vexpand(true);

  m_refTextBuffer = Gtk::TextBuffer::create();
  m_TextView.set_buffer(m_refTextBuffer);

  m_VBox.pack_start(m_Statusbar);

  show_all_children();
}

ExampleWindow::~ExampleWindow()
{
}

void ExampleWindow::build_main_menu(const Glib::RefPtr&lt;Gtk::Application&gt;&amp; app)
{
  //Create actions for menus and toolbars:
  auto refActionGroup = Gio::SimpleActionGroup::create();

  //File menu:
  refActionGroup-&gt;add_action("new",
    sigc::mem_fun(*this, &amp;ExampleWindow::on_menu_file_new));

  refActionGroup-&gt;add_action("pagesetup",
    sigc::mem_fun(*this, &amp;ExampleWindow::on_menu_file_page_setup));

  refActionGroup-&gt;add_action("printpreview",
    sigc::mem_fun(*this, &amp;ExampleWindow::on_menu_file_print_preview));

  refActionGroup-&gt;add_action("print",
    sigc::mem_fun(*this, &amp;ExampleWindow::on_menu_file_print));

  refActionGroup-&gt;add_action("quit",
    sigc::mem_fun(*this, &amp;ExampleWindow::on_menu_file_quit));

  insert_action_group("example", refActionGroup);

  // When the menubar is a child of a Gtk::Window, keyboard accelerators are not
  // automatically fetched from the Gio::Menu.
  // See the examples/book/menus/main_menu example for an alternative way of
  // adding the menubar when using Gtk::ApplicationWindow.
  app-&gt;set_accel_for_action("example.new", "&lt;Primary&gt;n");
  app-&gt;set_accel_for_action("example.print", "&lt;Primary&gt;p");
  app-&gt;set_accel_for_action("example.quit", "&lt;Primary&gt;q");

  m_refBuilder = Gtk::Builder::create();

  // Layout the actions in a menubar:
  Glib::ustring ui_menu_info =
    "&lt;interface&gt;"
    "  &lt;menu id='menu-example'&gt;"
    "    &lt;submenu&gt;"
    "      &lt;attribute name='label' translatable='yes'&gt;_File&lt;/attribute&gt;"
    "      &lt;section&gt;"
    "        &lt;item&gt;"
    "          &lt;attribute name='label' translatable='yes'&gt;_New&lt;/attribute&gt;"
    "          &lt;attribute name='action'&gt;example.new&lt;/attribute&gt;"
    "        &lt;/item&gt;"
    "      &lt;/section&gt;"
    "      &lt;section&gt;"
    "        &lt;item&gt;"
    "          &lt;attribute name='label' translatable='yes'&gt;Page _Setup...&lt;/attribute&gt;"
    "          &lt;attribute name='action'&gt;example.pagesetup&lt;/attribute&gt;"
    "        &lt;/item&gt;"
    "        &lt;item&gt;"
    "          &lt;attribute name='label' translatable='yes'&gt;Print Preview&lt;/attribute&gt;"
    "          &lt;attribute name='action'&gt;example.printpreview&lt;/attribute&gt;"
    "        &lt;/item&gt;"
    "        &lt;item&gt;"
    "          &lt;attribute name='label' translatable='yes'&gt;_Print...&lt;/attribute&gt;"
    "          &lt;attribute name='action'&gt;example.print&lt;/attribute&gt;"
    "        &lt;/item&gt;"
    "      &lt;/section&gt;"
    "      &lt;section&gt;"
    "        &lt;item&gt;"
    "          &lt;attribute name='label' translatable='yes'&gt;_Quit&lt;/attribute&gt;"
    "          &lt;attribute name='action'&gt;example.quit&lt;/attribute&gt;"
    "        &lt;/item&gt;"
    "      &lt;/section&gt;"
    "    &lt;/submenu&gt;"
    "  &lt;/menu&gt;"
    "&lt;/interface&gt;";

  try
  {
    m_refBuilder-&gt;add_from_string(ui_menu_info);
  }
  catch(const Glib::Error&amp; ex)
  {
    std::cerr &lt;&lt; "building menus failed: " &lt;&lt; ex.what();
  }

  // Layout the actions in a toolbar:
  Glib::ustring ui_toolbar_info =
    "&lt;!-- Generated with glade 3.18.3 --&gt;"
    "&lt;interface&gt;"
      "&lt;requires lib='gtk+' version='3.8'/&gt;"
      "&lt;object class='GtkToolbar' id='toolbar'&gt;"
        "&lt;property name='visible'&gt;True&lt;/property&gt;"
        "&lt;property name='can_focus'&gt;False&lt;/property&gt;"
        "&lt;child&gt;"
          "&lt;object class='GtkToolButton' id='toolbutton_new'&gt;"
            "&lt;property name='visible'&gt;True&lt;/property&gt;"
            "&lt;property name='can_focus'&gt;False&lt;/property&gt;"
            "&lt;property name='tooltip_text' translatable='yes'&gt;New&lt;/property&gt;"
            "&lt;property name='action_name'&gt;example.new&lt;/property&gt;"
            "&lt;property name='icon_name'&gt;document-new&lt;/property&gt;"
          "&lt;/object&gt;"
          "&lt;packing&gt;"
            "&lt;property name='expand'&gt;False&lt;/property&gt;"
            "&lt;property name='homogeneous'&gt;True&lt;/property&gt;"
          "&lt;/packing&gt;"
        "&lt;/child&gt;"
        "&lt;child&gt;"
          "&lt;object class='GtkToolButton' id='toolbutton_print'&gt;"
            "&lt;property name='visible'&gt;True&lt;/property&gt;"
            "&lt;property name='can_focus'&gt;False&lt;/property&gt;"
            "&lt;property name='tooltip_text' translatable='yes'&gt;Print&lt;/property&gt;"
            "&lt;property name='action_name'&gt;example.print&lt;/property&gt;"
            "&lt;property name='icon_name'&gt;document-print&lt;/property&gt;"
          "&lt;/object&gt;"
          "&lt;packing&gt;"
            "&lt;property name='expand'&gt;False&lt;/property&gt;"
            "&lt;property name='homogeneous'&gt;True&lt;/property&gt;"
          "&lt;/packing&gt;"
        "&lt;/child&gt;"
        "&lt;child&gt;"
          "&lt;object class='GtkSeparatorToolItem' id='separator1'&gt;"
            "&lt;property name='visible'&gt;True&lt;/property&gt;"
            "&lt;property name='can_focus'&gt;False&lt;/property&gt;"
          "&lt;/object&gt;"
          "&lt;packing&gt;"
            "&lt;property name='expand'&gt;False&lt;/property&gt;"
            "&lt;property name='homogeneous'&gt;False&lt;/property&gt;"
          "&lt;/packing&gt;"
        "&lt;/child&gt;"
        "&lt;child&gt;"
          "&lt;object class='GtkToolButton' id='toolbutton_quit'&gt;"
            "&lt;property name='visible'&gt;True&lt;/property&gt;"
            "&lt;property name='can_focus'&gt;False&lt;/property&gt;"
            "&lt;property name='tooltip_text' translatable='yes'&gt;Quit&lt;/property&gt;"
            "&lt;property name='action_name'&gt;example.quit&lt;/property&gt;"
            "&lt;property name='icon_name'&gt;application-exit&lt;/property&gt;"
          "&lt;/object&gt;"
          "&lt;packing&gt;"
            "&lt;property name='expand'&gt;False&lt;/property&gt;"
            "&lt;property name='homogeneous'&gt;True&lt;/property&gt;"
          "&lt;/packing&gt;"
        "&lt;/child&gt;"
      "&lt;/object&gt;"
    "&lt;/interface&gt;";

  try
  {
    m_refBuilder-&gt;add_from_string(ui_toolbar_info);
  }
  catch(const Glib::Error&amp; ex)
  {
    std::cerr &lt;&lt; "building toolbar failed: " &lt;&lt; ex.what();
  }

  // Get the menubar and add it to a container widget:
  auto object = m_refBuilder-&gt;get_object("menu-example");
  auto gmenu = Glib::RefPtr&lt;Gio::Menu&gt;::cast_dynamic(object);
  if (!gmenu)
    g_warning("GMenu not found");
  else
  {
    auto pMenuBar = Gtk::manage(new Gtk::MenuBar(gmenu));

    // Add the MenuBar to the window:
    m_VBox.pack_start(*pMenuBar, Gtk::PACK_SHRINK);
  }

  // Get the toolbar and add it to a container widget:
  Gtk::Toolbar* toolbar = nullptr;
  m_refBuilder-&gt;get_widget("toolbar", toolbar);
  if (!toolbar)
    g_warning("GtkToolbar not found");
  else
    m_VBox.pack_start(*toolbar, Gtk::PACK_SHRINK);
}

void ExampleWindow::on_printoperation_status_changed()
{
  Glib::ustring status_msg;

  if (m_refPrintFormOperation-&gt;is_finished())
  {
    status_msg = "Print job completed.";
  }
  else
  {
    //You could also use get_status().
    status_msg = m_refPrintFormOperation-&gt;get_status_string();
  }

  m_Statusbar.push(status_msg, m_ContextId);
}

void ExampleWindow::on_printoperation_done(Gtk::PrintOperationResult result)
{
  //Printing is "done" when the print data is spooled.

  if (result == Gtk::PRINT_OPERATION_RESULT_ERROR)
  {
    Gtk::MessageDialog err_dialog(*this, "Error printing form", false,
            Gtk::MESSAGE_ERROR, Gtk::BUTTONS_OK, true);
    err_dialog.run();
  }
  else if (result == Gtk::PRINT_OPERATION_RESULT_APPLY)
  {
    //Update PrintSettings with the ones used in this PrintOperation:
    m_refSettings = m_refPrintFormOperation-&gt;get_print_settings();
  }

  if (!m_refPrintFormOperation-&gt;is_finished())
  {
    //We will connect to the status-changed signal to track status
    //and update a status bar. In addition, you can, for example,
    //keep a list of active print operations, or provide a progress dialog.
    m_refPrintFormOperation-&gt;signal_status_changed().connect(sigc::mem_fun(*this,
                    &amp;ExampleWindow::on_printoperation_status_changed));
  }
}

void ExampleWindow::print_or_preview(Gtk::PrintOperationAction print_action)
{
  //Create a new PrintOperation with our PageSetup and PrintSettings:
  //(We use our derived PrintOperation class)
  m_refPrintFormOperation = PrintFormOperation::create();

  m_refPrintFormOperation-&gt;set_name(m_NameEntry.get_text() + " " + m_SurnameEntry.get_text());
  m_refPrintFormOperation-&gt;set_comments(m_refTextBuffer-&gt;get_text(false /*Don't include hidden*/));
  // In the printing/advanced example, the font will be set through a custom tab
  // in the print dialog.

  m_refPrintFormOperation-&gt;set_track_print_status();
  m_refPrintFormOperation-&gt;set_default_page_setup(m_refPageSetup);
  m_refPrintFormOperation-&gt;set_print_settings(m_refSettings);

  m_refPrintFormOperation-&gt;signal_done().connect(sigc::mem_fun(*this,
                  &amp;ExampleWindow::on_printoperation_done));
  try
  {
    m_refPrintFormOperation-&gt;run(print_action /* print or preview */, *this);
  }
  catch (const Gtk::PrintError&amp; ex)
  {
    //See documentation for exact Gtk::PrintError error codes.
    std::cerr &lt;&lt; "An error occurred while trying to run a print operation:"
        &lt;&lt; ex.what() &lt;&lt; std::endl;
  }
}

void ExampleWindow::on_menu_file_new()
{
  //Clear entries and textview:
  m_NameEntry.set_text("");
  m_SurnameEntry.set_text("");
  m_refTextBuffer-&gt;set_text("");
  m_TextView.set_buffer(m_refTextBuffer);
}

void ExampleWindow::on_menu_file_page_setup()
{
  //Show the page setup dialog, asking it to start with the existing settings:
  auto new_page_setup =
      Gtk::run_page_setup_dialog(*this, m_refPageSetup, m_refSettings);

  //Save the chosen page setup dialog for use when printing, previewing, or
  //showing the page setup dialog again:
  m_refPageSetup = new_page_setup;
}

void ExampleWindow::on_menu_file_print_preview()
{
  print_or_preview(Gtk::PRINT_OPERATION_ACTION_PREVIEW);
}

void ExampleWindow::on_menu_file_print()
{
  print_or_preview(Gtk::PRINT_OPERATION_ACTION_PRINT_DIALOG);
}

void ExampleWindow::on_menu_file_quit()
{
  hide();
}
</programlisting>
<!-- end inserted example code -->

</sect2>

</sect1>

</chapter>

<chapter id="chapter-recent-documents">
  <title>Documents récents</title>

  <para><application>gtkmm</application> fournit un moyen simple pour gérer les documents récemment utilisés. Les classes impliquées dans cette fonctionnalité sont <classname>RecentManager</classname>, <classname>RecentChooserDialog</classname>, <classname>RecentChooserMenu</classname>, <classname>RecentChooserWidget</classname> et <classname>RecentFilter</classname>.</para>
  <para>Chaque élément, dans la liste des fichiers récemment utilisés, est identifié par son URI et peut posséder des métadonnées associées. Les métadonnées peuvent être utilisées pour définir la façon dont le fichier doit être affiché, une description du fichier, son type MIME, quelle application l'a enregistré, s'il appartient en propre à l'application qui l'a enregistré et diverses autres informations.</para>
  <sect1 id="sec-recentmanager">
    <title>La classe RecentManager</title>
    <para lang="en">
      <classname>RecentManager</classname> acts as a database of
      recently used files. You use this class to register new files, remove
      files from the list, or look up recently used files. There is one list
      of recently used files per user.
    </para>
    <para>Il est possible de créer une nouvelle classe <classname>RecentManager</classname>, mais il est plus vraisemblable que vous souhaiterez vous servir de celle par défaut. Vous obtiendrez une référence sur cette dernière avec <methodname>get_default()</methodname>.</para>
    <para lang="en">
      <classname>RecentManager</classname> is the model of a model-view pattern,
      where the view is a class that implements the
      <classname>RecentChooser</classname> interface.
    </para>
    <sect2 id="recent-files-adding">
      <title>Ajout d'éléments à la liste des fichiers récents</title>
      <para>Pour ajouter un nouveau fichier à la liste des documents récents, dans le cas le plus simple, vous n'avez besoin que de fournir l'URI. Par exemple :</para>
      <programlisting>Glib::RefPtr&lt;Gtk::RecentManager&gt; recent_manager = Gtk::RecentManager::get_default();
recent_manager-&gt;add_item(uri);</programlisting>
      <para>Si vous voulez enregistrer un fichier avec ses métadonnées, passez un paramètre <classname>RecentManager::Data</classname> à la fonction membre <methodname>add_item()</methodname>. Les métadonnées pouvant être définies sur un élément fichier donné sont :</para>
      <itemizedlist id="list-file-metadata">
        <listitem>
          <para><varname>app_exec</varname> : la ligne de commande à utiliser pour atteindre cette ressource. Cette chaîne peut comporter les caractères d'échappement « f » et « u » ; ils seront respectivement développés sous forme du chemin d'accès à la ressource et de l'URI.</para>
        </listitem>
        <listitem>
          <para><varname>app_name</varname> : le nom de l'application qui a enregistré la ressource.</para>
        </listitem>
        <listitem>
          <para><varname>description</varname> : une courte description de la ressource sous forme d'une chaîne UTF-8.</para>
        </listitem>
        <listitem>
          <para><varname>display_name</varname> : le nom de la ressource à utiliser pour l'affichage sous forme d'une chaîne UTF-8.</para>
        </listitem>
        <listitem>
          <para><varname>groups</varname> : une liste des groupes associés à cet élément. Les groupes sont essentiellement des dénominations arbitraires associées à des ressources particulières. Ils peuvent être pensés en termes de « catégories » (telles que « courriel », « graphiques ») ou de marqueurs pour la ressource.</para>
        </listitem>
        <listitem>
          <para><varname>is_private</varname> : indique si la ressource ne doit être visible que des applications qui l'ont enregistrée ou non.</para>
        </listitem>
        <listitem>
          <para><varname>mime_type</varname> : le type MIME de la ressource.</para>
        </listitem>
      </itemizedlist>
      <para>En plus de la possibilité d'intégrer des éléments dans la liste, vous pouvez aussi faire une recherche d'éléments déjà présents dans la liste, les modifier ou les enlever.</para>
    </sect2>
    <sect2 id="recent-files-lookup">
      <title>Examen des éléments de la liste des fichiers récents</title>
      <para lang="en">
        To look up recently used files, <classname>RecentManager</classname>
        provides several functions. To look up a specific item by its URI, you
        can use the <methodname>lookup_item()</methodname> function, which will
        return a <classname>RecentInfo</classname> class. If the specified URI
        did not exist in the list of recent files,
        <methodname>lookup_item()</methodname> throws a
        <classname>RecentManagerError</classname> exception. For example:
      </para>
<programlisting lang="en">Glib::RefPtr&lt;Gtk::RecentInfo&gt; info;
try
{
  info = recent_manager-&gt;lookup_item(uri);
}
catch(const Gtk::RecentManagerError&amp; ex)
{
  std::cerr &lt;&lt; "RecentManagerError: " &lt;&lt; ex.what() &lt;&lt; std::endl;
}
if (info)
{
  // item was found
}</programlisting>
      <para lang="en">
        A <classname>RecentInfo</classname> object is essentially an object
        containing all of the metadata about a single recently-used file. You
        can use this object to look up any of the properties listed
        <link linkend="list-file-metadata">above</link>.
      </para>
      <para lang="en">
        If you don't want to look for a specific URI, but instead want to get a
        list of all recently used items, <classname>RecentManager</classname>
        provides the <methodname>get_items()</methodname> function. The return
        value of this function is a <classname>std::vector</classname> of all
        recently used files. The following code demonstrates how you might get a
        list of recently used files:
      </para>
      <programlisting lang="en">std::vector&lt; Glib::RefPtr&lt;Gtk::RecentInfo&gt; &gt; info_list = recent_manager-&gt;get_items();</programlisting>
      <para lang="en">
        The maximum age of items in the recently used files list can be set with
        <methodname>Gtk::Settings::property_gtk_recent_files_max_age()</methodname>.
        Default value: 30 days.
      </para>
    </sect2>
    <sect2 id="recent-files-modifying">
      <title>Modification de la liste des fichiers récents</title>
      <para>Vous pouvez parfois avoir besoin de modifier la liste des fichiers récents. Par exemple, si un fichier est déplacé ou renommé, vous pouvez mettre à jour l'emplacement ou le nom du fichier dans la liste des fichiers récents pour éviter de pointer vers quelque chose d'incorrect. Vous pouvez mettre à jour l'emplacement d'un élément avec <methodname>move_item()</methodname>.</para>
      <para lang="en">
        In addition to changing a file's URI, you can also remove items from the
        list, either one at a time or by clearing them all at once. The former
        is accomplished with <methodname>remove_item()</methodname>, the latter with
        <methodname>purge_items()</methodname>.
      </para>
      <note>
        <para>Les fonctions <methodname>move_item()</methodname>, <methodname>remove_item()</methodname> et <methodname>purge_items()</methodname> n'ont aucun effet concret sur les fichiers auxquels les URI se référent ; elles ne font que modifier la liste.</para>
      </note>
    </sect2>
  </sect1>

  <sect1 id="sec-recentchooser">
    <title>La classe RecentChooser</title>
    <para lang="en">
      <classname>RecentChooser</classname> is an interface that can be
      implemented by widgets displaying the list of recently used files.
      <application>gtkmm</application> provides four built-in implementations for choosing recent files:
      <classname>RecentChooserWidget</classname>,
      <classname>RecentChooserDialog</classname>,
      <classname>RecentChooserMenu</classname>, and the deprecated
      <classname>RecentAction</classname>.
    </para>
    <para><classname>RecentChooserWidget</classname> est un simple élément graphique pour un affichage de la liste des fichiers récemment utilisés. <classname>RecentChooserWidget</classname> est l'élément de base de la classe <classname>RecentChooserDialog</classname>, mais vous pouvez l'incorporer dans votre interface utilisateur si vous le souhaitez.</para>
    <para lang="en">
      <classname>RecentChooserMenu</classname> allows you to list recently used
      files as a menu.
    </para>
    <sect2 id="recentchooserdialog-example">
      <title lang="en">Simple RecentChooserDialog example</title>
      <para lang="en">
        Shown below is a simple example of how to use the
        <classname>RecentChooserDialog</classname> class in a program.
        This simple program has a menubar with a
        <guimenuitem>Recent Files Dialog</guimenuitem> menu item.
        When you select this menu item, a dialog pops up showing the list of
        recently used files.
      </para>
      <note>
        <para>À la première utilisation d'un programme se servant de la structure des Fichiers récents, la boîte de dialogue peut initialement être vide. Sinon, elle devrait afficher la liste des documents récemment utilisés enregistrés par d'autres applications.</para>
      </note>
      <para>Après avoir sélectionné l'élément de menu <guimenuitem>Boîte de dialogue fichiers récents</guimenuitem>, vous voyez quelque chose de semblable à la fenêtre ci-après.</para>
      <screenshot>
          <graphic format="PNG" fileref="figures/recentchooserdialog.png"/>
      </screenshot>
<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/recent_files?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>examplewindow.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLEWINDOW_H
#define GTKMM_EXAMPLEWINDOW_H

#include &lt;gtkmm.h&gt;

class ExampleWindow : public Gtk::Window
{
public:
  ExampleWindow(const Glib::RefPtr&lt;Gtk::Application&gt;&amp; app);
  virtual ~ExampleWindow();

protected:
  //Signal handlers:
  void on_menu_file_recent_files_item();
  void on_menu_file_recent_files_dialog();
  void on_menu_file_quit();
  void on_menu_file_new();

  //Child widgets:
  Gtk::Box m_Box;

  Glib::RefPtr&lt;Gtk::Builder&gt; m_refBuilder;
  Glib::RefPtr&lt;Gio::SimpleActionGroup&gt; m_refActionGroup;

  Glib::RefPtr&lt;Gtk::RecentManager&gt; m_refRecentManager;
};

#endif //GTKMM_EXAMPLEWINDOW_H
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;gtkmm/application.h&gt;

int main(int argc, char *argv[])
{
  auto app = Gtk::Application::create(argc, argv, "org.gtkmm.example");

  ExampleWindow window(app);

  //Shows the window and returns when it is closed.
  return app-&gt;run(window);
}
</programlisting>
<para lang="en">File: <filename>examplewindow.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;iostream&gt;

ExampleWindow::ExampleWindow(const Glib::RefPtr&lt;Gtk::Application&gt;&amp; app)
: m_Box(Gtk::ORIENTATION_VERTICAL),
  m_refRecentManager(Gtk::RecentManager::get_default())
{
  set_title("recent files example");
  set_default_size(200, 200);

  //We can put a MenuBar at the top of the box and other stuff below it.
  add(m_Box);

  //Create actions for menus and toolbars:
  m_refActionGroup = Gio::SimpleActionGroup::create();

  //File menu:
  m_refActionGroup-&gt;add_action("new",
    sigc::mem_fun(*this, &amp;ExampleWindow::on_menu_file_new));

  //A menu item to open the recent-files dialog:
  m_refActionGroup-&gt;add_action("recent-files-dialog",
    sigc::mem_fun(*this, &amp;ExampleWindow::on_menu_file_recent_files_dialog) );

  m_refActionGroup-&gt;add_action("quit",
    sigc::mem_fun(*this, &amp;ExampleWindow::on_menu_file_quit) );

  insert_action_group("example", m_refActionGroup);


  m_refBuilder = Gtk::Builder::create();

  // When the menubar is a child of a Gtk::Window, keyboard accelerators are not
  // automatically fetched from the Gio::Menu.
  // See the examples/book/menus/main_menu example for an alternative way of
  // adding the menubar when using Gtk::ApplicationWindow.
  app-&gt;set_accel_for_action("example.new", "&lt;Primary&gt;n");
  app-&gt;set_accel_for_action("example.recent-files-dialog", "&lt;Primary&gt;o");
  app-&gt;set_accel_for_action("example.quit", "&lt;Primary&gt;q");

  //Layout the actions in a menubar and a toolbar:
  const char* ui_info =
    "&lt;interface&gt;"
    "  &lt;menu id='menubar'&gt;"
    "    &lt;submenu&gt;"
    "      &lt;attribute name='label' translatable='yes'&gt;_File&lt;/attribute&gt;"
    "      &lt;item&gt;"
    "        &lt;attribute name='label' translatable='yes'&gt;_New&lt;/attribute&gt;"
    "        &lt;attribute name='action'&gt;example.new&lt;/attribute&gt;"
    "        &lt;attribute name='accel'&gt;&amp;lt;Primary&amp;gt;n&lt;/attribute&gt;"
    "      &lt;/item&gt;"
    "      &lt;item&gt;"
    "        &lt;attribute name='label' translatable='yes'&gt;Recent Files _Dialog&lt;/attribute&gt;"
    "        &lt;attribute name='action'&gt;example.recent-files-dialog&lt;/attribute&gt;"
    "        &lt;attribute name='accel'&gt;&amp;lt;Primary&amp;gt;o&lt;/attribute&gt;"
    "      &lt;/item&gt;"
    "      &lt;item&gt;"
    "        &lt;attribute name='label' translatable='yes'&gt;_Quit&lt;/attribute&gt;"
    "        &lt;attribute name='action'&gt;example.quit&lt;/attribute&gt;"
    "        &lt;attribute name='accel'&gt;&amp;lt;Primary&amp;gt;q&lt;/attribute&gt;"
    "      &lt;/item&gt;"
    "    &lt;/submenu&gt;"
    "  &lt;/menu&gt;"
    "  &lt;object class='GtkToolbar' id='toolbar'&gt;"
    "    &lt;property name='visible'&gt;True&lt;/property&gt;"
    "    &lt;property name='can_focus'&gt;False&lt;/property&gt;"
    "    &lt;child&gt;"
    "      &lt;object class='GtkToolButton' id='toolbutton_new'&gt;"
    "        &lt;property name='visible'&gt;True&lt;/property&gt;"
    "        &lt;property name='can_focus'&gt;False&lt;/property&gt;"
    "        &lt;property name='tooltip_text' translatable='yes'&gt;New&lt;/property&gt;"
    "        &lt;property name='action_name'&gt;example.new&lt;/property&gt;"
    "        &lt;property name='icon_name'&gt;document-new&lt;/property&gt;"
    "      &lt;/object&gt;"
    "      &lt;packing&gt;"
    "        &lt;property name='expand'&gt;False&lt;/property&gt;"
    "        &lt;property name='homogeneous'&gt;True&lt;/property&gt;"
    "      &lt;/packing&gt;"
    "    &lt;/child&gt;"
    "    &lt;child&gt;"
    "      &lt;object class='GtkToolButton' id='toolbutton_quit'&gt;"
    "        &lt;property name='visible'&gt;True&lt;/property&gt;"
    "        &lt;property name='can_focus'&gt;False&lt;/property&gt;"
    "        &lt;property name='tooltip_text' translatable='yes'&gt;Quit&lt;/property&gt;"
    "        &lt;property name='action_name'&gt;example.quit&lt;/property&gt;"
    "        &lt;property name='icon_name'&gt;application-exit&lt;/property&gt;"
    "      &lt;/object&gt;"
    "      &lt;packing&gt;"
    "        &lt;property name='expand'&gt;False&lt;/property&gt;"
    "        &lt;property name='homogeneous'&gt;True&lt;/property&gt;"
    "      &lt;/packing&gt;"
    "    &lt;/child&gt;"
    "  &lt;/object&gt;"
    "&lt;/interface&gt;";

  try
  {
    m_refBuilder-&gt;add_from_string(ui_info);
  }
  catch(const Glib::Error&amp; ex)
  {
    std::cerr &lt;&lt; "building menubar and toolbar failed: " &lt;&lt;  ex.what();
  }

  //Get the menubar and toolbar widgets, and add them to a container widget:
  auto object = m_refBuilder-&gt;get_object("menubar");
  auto gmenu = Glib::RefPtr&lt;Gio::Menu&gt;::cast_dynamic(object);
  if (gmenu)
  {
    //Menubar:
    auto pMenubar = Gtk::manage(new Gtk::MenuBar(gmenu));
    m_Box.pack_start(*pMenubar, Gtk::PACK_SHRINK);
  }
  else
    g_warning("GMenu not found");

  Gtk::Toolbar* pToolbar = nullptr;
  m_refBuilder-&gt;get_widget("toolbar", pToolbar);
  if (pToolbar)
    //Toolbar:
    m_Box.pack_start(*pToolbar, Gtk::PACK_SHRINK);
  else
    g_warning("GtkToolbar not found");

  show_all_children();
}

ExampleWindow::~ExampleWindow()
{
}

void ExampleWindow::on_menu_file_new()
{
  std::cout &lt;&lt; " New File" &lt;&lt; std::endl;
}

void ExampleWindow::on_menu_file_quit()
{
  hide(); //Closes the main window to stop the app-&gt;run().
}

void ExampleWindow::on_menu_file_recent_files_dialog()
{
  Gtk::RecentChooserDialog dialog(*this, "Recent Files", m_refRecentManager);
  dialog.add_button("Select File", Gtk::RESPONSE_OK);
  dialog.add_button("_Cancel", Gtk::RESPONSE_CANCEL);

  const int response = dialog.run();
  dialog.hide();
  if(response == Gtk::RESPONSE_OK)
  {
    std::cout &lt;&lt; "URI selected = " &lt;&lt; dialog.get_current_uri() &lt;&lt; std::endl;
  }
}

</programlisting>
<!-- end inserted example code -->
      <para lang="en">
        The constructor for <classname>ExampleWindow</classname> creates the
        menu and the toolbar using <classname>Builder</classname> (see <xref linkend="chapter-menus-and-toolbars"/> for more information). It then adds
        the menu and the toolbar to the window.
      </para>
    </sect2>
    <sect2 id="recent-files-filtering">
      <title>Filtrage des fichiers récents</title>
      <para>Pour chacune des classes <classname>RecentChooser</classname>, si vous ne souhaitez pas afficher tous les éléments de la liste des fichiers récents, vous pouvez filtrer la liste pour ne montrer que ce que vous souhaitez. Vous pouvez filtrer la liste avec l'aide de la classe <classname>RecentFilter</classname>. Cette classe vous permet de filtrer les fichiers par le nom (<methodname>add_pattern()</methodname>), leur type MIME (<methodname>add_mime_type()</methodname>), l'application qui les a enregistrés (<methodname>add_application()</methodname>) ou par une fonction de filtrage personnalisée (<methodname>add_custom()</methodname>). Elle offre aussi la possibilité de filtrer sur la date de dernière modification et sur les groupes dont le fichier fait partie.</para>
      <para>Après avoir créé et réglé le filtre pour qu'il corresponde uniquement aux fichiers souhaités, vous pouvez appliquer le filtre à l'élément graphique de sélection avec la fonction <methodname>RecentChooser::add_filter()</methodname>.</para>
    </sect2>
  </sect1>
</chapter>

<chapter id="chapter-plugs-sockets">
  <title>Greffons et connecteurs</title>
  <sect1 id="sec-plugs-sockets-overview">
    <title>Aperçu</title>
    <para>Parfois, il peut se révéler utile de pouvoir incorporer un élément graphique d'une autre application dans votre propre application. <application>gtkmm</application> permet cela grâce aux classes <classname>Gtk::Socket</classname> et <classname>Gtk::Plug</classname>. Il est peu vraisemblable que beaucoup d'applications aient besoin de cette fonctionnalité, mais dans les rares cas où vous auriez besoin d'afficher un élément graphique fonctionnant dans un processus tout à fait différent, ces classes peuvent être d'une grande aide.</para>
    <para>La communication entre un objet <classname>Socket</classname> et un objet <classname>Plug</classname> s'effectue suivant le protocole XEmbed. Ce protocole a aussi été implémenté dans d'autres boîtes à outils (par exemple, Qt) ; cela permet un niveau d'intégration identique lorsqu'on incorpore un élément graphique Qt dans GTK+ ou vice versa.</para>
    <para>Les <classname>Sockets</classname> et <classname>Plugs</classname> collaborent par l'intermédiaire des identifiants de leurs fenêtres. Un objet <classname>Socket</classname> et un objet <classname>Plug</classname> ont tous deux des ID que l'on peut retrouver avec leurs fonctions membres <methodname>get_id()</methodname>. L'utilisation de ces ID sera explicitée plus bas dans la <xref linkend="sec-connecting-plugs-sockets"/>.</para>
    <sect2 id="sec-sockets">
      <title>Connecteurs</title>
      <para>Un objet <classname>Socket</classname> est une sorte d'élément graphique conteneur spécial qui autorise la possibilité d'incorporer des éléments graphiques d'un processus dans un autre de manière totalement transparente pour l'utilisateur.</para>
    </sect2>
    <sect2 id="sec-plugs">
      <title>Greffons</title>
      <para>Un objet <classname>Plug</classname> est une variété de fenêtre particulière qu'il est possible de greffer dans un objet <classname>Socket</classname>. Outre les propriétés et les fonctions membres habituelles de la classe <classname>Gtk::Window</classname>, l'objet <classname>Plug</classname> fournit un constructeur qui prend comme paramètre l'ID d'un objet <classname>Socket</classname> ; l'objet <classname>Plug</classname> va automatiquement s'incorporer dans l'objet <classname>Socket</classname> qui a l'ID correspondant.</para>
      <para>Comme un objet <classname>Plug</classname> n'est qu'un type spécial de classe <classname>Gtk::Window</classname>, vous pouvez lui ajouter des conteneurs ou des éléments graphiques exactement comme vous auriez fait pour une autre fenêtre.</para>
    </sect2>
    <sect2 id="sec-connecting-plugs-sockets">
      <title>Branchement des greffons et des connecteurs</title>
      <para lang="en">
        After a <classname>Socket</classname> or <classname>Plug</classname>
        object is realized, you can obtain its ID with its
        <methodname>get_id()</methodname> function. This ID can then be shared with
        other processes so that other processes know how to connect to
        each other.
      </para>
      <para lang="en">
        There are two basic strategies that can be used:
        <itemizedlist>
          <listitem>
            <para lang="en">
              Create a <classname>Socket</classname> object in one process and
              pass the ID of that <classname>Socket</classname> to another
              process so that it can create a <classname>Plug</classname> object
              by specifying the given <classname>Socket</classname> ID in its
              constructor. There is no way to assign a
              <classname>Plug</classname> to a particular
              <classname>Socket</classname> after creation, so you must pass the
              <classname>Socket</classname> ID to the
              <classname>Plug</classname>'s constructor.
            </para>
          </listitem>
          <listitem>
            <para lang="en">
              Create a <classname>Plug</classname> independantly from any
              particular <classname>Socket</classname> and pass the ID of the
              <classname>Plug</classname> to other processes that need to use
              it. The ID of the <classname>Plug</classname> can be associated
              with a particular <classname>Socket</classname> object using the
              <methodname>Socket::add_id()</methodname> function. This is the
              approach used in the example below.
            </para>
          </listitem>
        </itemizedlist>
      </para>
    </sect2>
  </sect1>
  <sect1 id="sec-plugs-sockets-example">
    <title>Exemple greffons et connecteurs</title>
    <para lang="en">
      The following is a simple example of using sockets and plugs. The method
      of communication between processes is deliberately kept very simple: The
      <classname>Plug</classname> writes its ID out to a text file named
      <filename>plug.id</filename> and the process with the socket reads the ID
      from this file. In a real program, you may want to use a more
      sophisticated method of inter-process communication.
    </para>
<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/socket/?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>plug.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include &lt;iostream&gt;
#include &lt;fstream&gt;
#include &lt;gtkmm.h&gt;
#include &lt;gtkmm/plug.h&gt;
#include &lt;glib/gstdio.h&gt;

using namespace std;

const char* id_filename = "plug.id";

void on_embed()
{
  cout &lt;&lt; "I've been embedded." &lt;&lt; endl;
}

class MyPlug : public Gtk::Plug
{
  public:
    MyPlug() :
      m_label("I am the plug")
  {
    set_size_request(150, 100);
    add(m_label);
    signal_embedded().connect(sigc::ptr_fun(on_embed));
    show_all_children();
  }

  private:
    Gtk::Label m_label;
};


int main(int argc, char** argv)
{
  // The plug and the socket have different application ids, so they can run
  // simultaneously.
  auto app =
    Gtk::Application::create(argc, argv, "org.gtkmm.example.plug");
  MyPlug plug;
  plug.show();

  ofstream out(id_filename);
  out &lt;&lt; plug.get_id();
  out.close();
  cout &lt;&lt; "The window ID is: " &lt;&lt; plug.get_id() &lt;&lt; endl;

  app-&gt;run(plug);

  // remove the ID file when the program exits
  g_remove(id_filename);
  return 0;
}
</programlisting>
<para lang="en">File: <filename>socket.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include &lt;iostream&gt;
#include &lt;fstream&gt;
#include &lt;gtkmm.h&gt;
#include &lt;gtkmm/socket.h&gt;

using namespace std;

const char* id_filename = "plug.id";

void plug_added()
{
  cout &lt;&lt; "A plug was added" &lt;&lt; endl;
}

bool plug_removed()
{
  cout &lt;&lt; "A Plug was removed" &lt;&lt; endl;
  return true;
}

class MySocketWindow : public Gtk::Window
{
  public:
    MySocketWindow()
    {
      ifstream infile(id_filename);
      if (infile)
      {
        auto socket = Gtk::manage(new Gtk::Socket());
        add(*socket);
        socket-&gt;signal_plug_added().connect(sigc::ptr_fun(plug_added));
        socket-&gt;signal_plug_removed().connect(sigc::ptr_fun(plug_removed));
        ::Window plug_id = 0;
        infile &gt;&gt; plug_id;
        infile.close();
        socket-&gt;add_id(plug_id);
      }
      else
      {
        auto label = Gtk::manage(
            new Gtk::Label(
              "Plug id file not found.\n Make sure plug is running."));
        add(*label);
        set_size_request(150, 50);
      }
      show_all();
    }
};

int main(int argc, char** argv)
{
  // The plug and the socket have different application ids, so they can run
  // simultaneously.
  auto app =
    Gtk::Application::create(argc, argv, "org.gtkmm.example.socket");
  MySocketWindow win;
  app-&gt;run(win);
  return 0;
}
</programlisting>
<!-- end inserted example code -->
    <para>Cet exemple crée deux exécutables : <filename>socket</filename> et <filename>plug</filename>. L'idée est que <filename>socket</filename> ait une fenêtre d'application qui accueille un élément graphique issu du programme <filename>plug</filename>. Compte tenu de la manière dont cet exemple est conçu, <filename>plug</filename> doit être lancé avant que <filename>socket</filename> ne démarre. Pour voir cet exemple en action, exécutez les commandes suivantes dans l'ordre indiqué à partir du répertoire de l'exemple :</para>
    <para>Lancez le programme <filename>plug</filename> et envoyez-le en arrière-plan (ou simplement utilisez un terminal différent) :</para>
    <screen>$ ./plug &amp;</screen>
    <para>Après cette action, vous devriez voir s'afficher :</para>
    <screen>The window ID is: 69206019</screen>
    <para>puis lancez le programme <filename>socket</filename> :</para>
    <screen>$ ./socket</screen>
    <para>Après avoir lancé <filename>socket</filename>, vous devriez voir les sorties suivantes sur le terminal :</para>
    <screen>I've been embedded.
A plug was added</screen>
    <para>La première ligne correspond à la sortie du programme <filename>plug</filename>, après qu'il a reçu notification qu'il a été incorporé dans l'objet <classname>Socket</classname>. La deuxième ligne a été émise par l'objet <filename>socket</filename> en réponse au signal <methodname>plug_added</methodname>. Si tout a été effectuée comme indiqué ci-dessus, la fenêtre <filename>socket</filename> doit ressembler grosso modo à quelque chose comme :</para>
    <screenshot>
      <graphic format="PNG" fileref="figures/socket.png"/>
    </screenshot>
    <para>Si, pour une quelconque raison, l'objet <classname>Socket</classname> ne peut pas recevoir l'objet <classname>Plug</classname>, la fenêtre ressemblera à :</para>
    <screenshot>
      <graphic format="PNG" fileref="figures/socket-fail.png"/>
    </screenshot>
  </sect1>
</chapter>

<chapter id="chapter-keyboardevents">
  <title lang="en">Keyboard Events</title>
  <para lang="en">
    X events differ in some ways from other signals. These differences are described
    in the <link linkend="sec-xeventsignals">X Event signals</link> section in
    the appendix. Here we will use keyboard events to show how X events can be
    used in a program.
  </para>
  <sect1 id="sec-keyboardevents-overview">
    <title>Aperçu</title>
    <para lang="en">
      Whenever you press or release a key, an event is emitted. You can connect
      a signal handler to handle such events.
    </para>
    <para lang="en">
      To receive the keyboard events, you must first call the
      <methodname>Gtk::Widget::add_events()</methodname> function with a bit
      mask of the events you're interested in. The event signal handler will
      receive an argument that depends on the type of event. For keyboard
      events it's a <type>GdkEventKey*</type>. As discribed in the
      <link linkend="sec-xeventsignals">appendix</link>, the event signal handler
      returns a <type>bool</type> value, to indicate that the signal is fully
      handled (<literal>true</literal>) or allow event propagation
      (<literal>false</literal>).
    </para>
    <para lang="en">
      To determine which key was pressed or released, you read the value of
      <varname>GdkEventKey::keyval</varname> and compare it with a constant in the
      <filename>&lt;gdk/gdkkeysyms.h&gt;</filename> header file. The states of
      modifier keys (shift, ctrl, etc.) are available as bit-flags in
      <varname>GdkEventKey::state</varname>.
    </para>
    <para lang="en">
      Here's a simple example:
<programlisting lang="en">
bool on_key_press_or_release_event(GdkEventKey* event)
{
  if (event-&gt;type == GDK_KEY_PRESS &amp;&amp;
    event-&gt;keyval == GDK_KEY_1 &amp;&amp;
    (event-&gt;state &amp; (GDK_SHIFT_MASK | GDK_CONTROL_MASK | GDK_MOD1_MASK)) == GDK_MOD1_MASK)
  {
    handle_alt_1_press(); // GDK_MOD1_MASK is normally the Alt key
    return true;
  }
  return false;
}

Gtk::Entry m_entry; // in a class definition

// in the class constructor
m_entry.signal_key_press_event().connect( sigc::ptr_fun(&amp;on_key_press_or_release_event) );
m_entry.signal_key_release_event().connect( sigc::ptr_fun(&amp;on_key_press_or_release_event) );
m_entry.add_events(Gdk::KEY_PRESS_MASK | Gdk::KEY_RELEASE_MASK);
</programlisting>
    </para>

    <sect2 id="keyboardevents-simple-example">
    <title>Exemple</title>
      <para lang="en">
        In this example there are three keyboard shortcuts:
        <keycap>Alt</keycap>+<keycap>1</keycap> selects the first radio button,
        <keycap>Alt</keycap>+<keycap>2</keycap> selects the second one, and the
        <keycap>Esc</keycap> key hides (closes) the window.
        The default event signal handler is overridden, as described in the
        <link linkend="sec-overriding-default-signal-handlers">Overriding default signal handlers</link>
        section in the appendix.
      </para>

      <figure id="figure-keyboardevents-simple">
        <title lang="en">Keyboard Events - Simple</title>
        <screenshot>
          <graphic format="PNG" fileref="figures/keyboardevents_simple.png"/>
        </screenshot>
      </figure>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/keyboard_events/simple/?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>examplewindow.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLEWINDOW_H
#define GTKMM_EXAMPLEWINDOW_H

#include &lt;gtkmm.h&gt;

class ExampleWindow : public Gtk::Window
{
public:

  ExampleWindow();
  virtual ~ExampleWindow();

private:
  //Override default signal handler:
  bool on_key_press_event(GdkEventKey* event) override;

  Gtk::Grid m_container;
  Gtk::RadioButton m_first;
  Gtk::RadioButton m_second;
};

#endif //GTKMM_EXAMPLEWINDOW_H
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;gtkmm/application.h&gt;

int main(int argc, char *argv[])
{
  auto app = Gtk::Application::create(argc, argv, "org.gtkmm.example");

  ExampleWindow window;

  //Shows the window and returns when it is closed.
  return app-&gt;run(window);
}
</programlisting>
<para lang="en">File: <filename>examplewindow.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"

ExampleWindow::ExampleWindow()
{
  set_title("Keyboard Events");
  set_border_width(10);
  add(m_container);

  // Radio buttons:
  m_first.set_label("First");
  m_second.set_label("Second");

  m_second.join_group(m_first);
  m_first.set_active();

  // Main Container:
  m_container.add(m_first);
  m_container.add(m_second);

  // Events.
  // We override the default event signal handler.
  add_events(Gdk::KEY_PRESS_MASK);

  show_all_children();
}

bool ExampleWindow::on_key_press_event(GdkEventKey* key_event)
{
  //GDK_MOD1_MASK -&gt; the 'alt' key(mask)
  //GDK_KEY_1 -&gt; the '1' key
  //GDK_KEY_2 -&gt; the '2' key

  //select the first radio button, when we press alt + 1
  if((key_event-&gt;keyval == GDK_KEY_1) &amp;&amp;
    (key_event-&gt;state &amp;(GDK_SHIFT_MASK | GDK_CONTROL_MASK | GDK_MOD1_MASK)) == GDK_MOD1_MASK)
  {
    m_first.set_active();
    //returning true, cancels the propagation of the event
    return true;
  }
  else if((key_event-&gt;keyval == GDK_KEY_2) &amp;&amp;
    (key_event-&gt;state &amp; (GDK_SHIFT_MASK | GDK_CONTROL_MASK | GDK_MOD1_MASK)) == GDK_MOD1_MASK)
  {
    //and the second radio button, when we press alt + 2
    m_second.set_active();
    return true;
  }
  else if(key_event-&gt;keyval == GDK_KEY_Escape)
  {
    //close the window, when the 'esc' key is pressed
    hide();
    return true;
  }

  //if the event has not been handled, call the base class
  return Gtk::Window::on_key_press_event(key_event);
}

ExampleWindow::~ExampleWindow()
{
}

</programlisting>
<!-- end inserted example code -->
    </sect2>
  </sect1>

  <sect1 id="sec-keyboardevents-propagation">
    <title lang="en">Event Propagation</title>
    <para lang="en">
      Event propagation means that, when an event is emitted on a particular
      widget, it can be passed to its parent widget (and that widget can pass
      it to its parent, and so on) and, if the parent has an event handler,
      that handler will be called. 
    </para>
    <para lang="en">
      Contrary to other events, keyboard events are first sent to the toplevel window
      (<classname>Gtk::Window</classname>), where it will be checked
      for any keyboard shortcuts that may be set (accelerator keys and mnemonics,
      used for selecting menu items from the keyboard). After this (and assuming
      the event wasn't handled), it is sent to the widget which has focus,
      and the propagation begins from there.
    </para>
    <para lang="en">
      The event will propagate until it reaches the top-level widget, or until
      you stop the propagation by returning <literal>true</literal> from an
      event handler.
    </para>
    <para lang="en">
      Notice, that after canceling an event, no other function will be called
      (even if it is from the same widget).
    </para>

    <sect2 id="keyboardevents-propagation-example">
    <title>Exemple</title>
      <para lang="en">
        In this example there are three event handlers that are called after
        <classname>Gtk::Window</classname>'s default event handler, one in the
        <classname>Gtk::Entry</classname>, one in the <classname>Gtk::Grid</classname>
        and one in the <classname>Gtk::Window</classname>.
      </para>
      <para lang="en">
        In the <classname>Gtk::Window</classname>, we have also the default handler
        overridden (<methodname>on_key_release_event()</methodname>), and
        another handler being called before the default handler
        (<methodname>windowKeyReleaseBefore()</methodname>).
      </para>
      <para lang="en">
        The purpose of this example is to show the steps the event takes when it is emitted.
      </para>
      <para lang="en">
        When you write in the entry, a key release event will be emitted,
        which will go first to the toplevel window (<classname>Gtk::Window</classname>),
        since we have one event handler set to be called before, that's what is
        called first (<methodname>windowKeyReleaseBefore()</methodname>).
        Then the default handler is called (which we have overridden), and after
        that the event is sent to the widget that has focus,
        the <classname>Entry</classname> in our example and, depending on whether we let
        it propagate, it can reach the <classname>Grid</classname>'s and the
        <classname>Window</classname>'s event handlers. If it propagates,
        the text you're writing will appear in the <classname>Label</classname>
        above the <classname>Entry</classname>.
      </para>

      <figure id="figure-keyboardevents-propagation">
        <title lang="en">Keyboard Events - Event Propagation</title>
        <screenshot>
          <graphic format="PNG" fileref="figures/keyboardevents_propagation.png"/>
        </screenshot>
      </figure>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/keyboard_events/propagation/?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>examplewindow.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EVENT_PROPAGATION_H
#define GTKMM_EVENT_PROPAGATION_H

#include &lt;gtkmm.h&gt;

class ExampleWindow : public Gtk::Window
{
public:

  ExampleWindow();
  virtual ~ExampleWindow();

private:
  //Override default signal handler:
  bool on_key_release_event(GdkEventKey* event) override;

  bool entryKeyRelease(GdkEventKey* event);
  bool gridKeyRelease(GdkEventKey* event);
  bool windowKeyReleaseBefore(GdkEventKey* event);
  bool windowKeyRelease(GdkEventKey* event);

  Gtk::Grid m_container;

  Gtk::Label m_label;
  Gtk::Entry m_entry;
  Gtk::CheckButton m_checkbutton_can_propagate;
};

#endif //GTKMM_EVENT_PROPAGATION_H
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;gtkmm/application.h&gt;

int main(int argc, char *argv[])
{
  auto app = Gtk::Application::create(argc, argv, "org.gtkmm.example");

  ExampleWindow window;

  //Shows the window and returns when it is closed.
  return app-&gt;run(window);
}
</programlisting>
<para lang="en">File: <filename>examplewindow.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;iostream&gt;

ExampleWindow::ExampleWindow()
{
  add(m_container);
  set_title("Event Propagation");
  set_border_width(10);

  m_label.set_label("A label");
  m_checkbutton_can_propagate.set_label("Can Propagate");
  m_checkbutton_can_propagate.set_active();

  // Main Container
  m_container.set_orientation(Gtk::ORIENTATION_VERTICAL);
  m_container.add(m_label);
  m_container.add(m_entry);
  m_container.add(m_checkbutton_can_propagate);

  // Events
  add_events(Gdk::KEY_RELEASE_MASK);

  m_entry.signal_key_release_event().connect(
    sigc::mem_fun(*this, &amp;ExampleWindow::entryKeyRelease));

  m_container.signal_key_release_event().connect(
    sigc::mem_fun(*this, &amp;ExampleWindow::gridKeyRelease));

  // Called before the default event signal handler.
  signal_key_release_event().connect(
    sigc::mem_fun(*this, &amp;ExampleWindow::windowKeyReleaseBefore), false);

  // Called after the default event signal handler.
  signal_key_release_event().connect(
    sigc::mem_fun(*this, &amp;ExampleWindow::windowKeyRelease));

  show_all_children();
}

//By changing the return value we allow, or don't allow, the event to propagate to other elements.
bool ExampleWindow::entryKeyRelease(GdkEventKey* /* event */ )
{
  std::cout &lt;&lt; "Entry" &lt;&lt; std::endl;

  if(m_checkbutton_can_propagate.get_active())
  {
    return false;
  }

  return true;
}

bool ExampleWindow::gridKeyRelease(GdkEventKey* /* event */ )
{
  std::cout &lt;&lt; "Grid" &lt;&lt; std::endl;

  //Let it propagate:
  return false;
}

bool ExampleWindow::windowKeyReleaseBefore(GdkEventKey* /* event */ )
{
  std::cout &lt;&lt; "Window before" &lt;&lt; std::endl;
  return false;
}

bool ExampleWindow::on_key_release_event(GdkEventKey* key_event)
{
  std::cout &lt;&lt; "Window overridden" &lt;&lt; std::endl;

  // call base class function (to get the normal behaviour)
  return Gtk::Window::on_key_release_event(key_event);
}

// This will set the entry's text in the label, every time a key is pressed.
bool ExampleWindow::windowKeyRelease(GdkEventKey* /* event */ )
{
  std::cout &lt;&lt; "Window after";

  //checking if the entry is on focus, otherwise the label would get changed by pressing keys
  //on the window (when the entry is not on focus), even if m_checkbutton_can_propagate wasn't active
  if(m_entry.has_focus())
  {
    m_label.set_text(m_entry.get_text());
    std::cout &lt;&lt; ", " &lt;&lt; m_entry.get_text();
  }
  std::cout &lt;&lt; std::endl;

  return true;
}

ExampleWindow::~ExampleWindow()
{
}

</programlisting>
<!-- end inserted example code -->
    </sect2>
  </sect1>
</chapter>

<chapter id="chapter-chapter-timeouts">
<title>Fonctions à délai échu, d'entrées/sorties et de temporisation</title>

<sect1 id="sec-timeouts">
<title>Fonctions à délai échu</title>

<para lang="en">
You may be wondering how to make <application>gtkmm</application> do useful work while it's idling along. Happily,
you have several options. Using the following methods you can create a timeout
method that will be called every few milliseconds.
</para>

<para>
<programlisting lang="en">
sigc::connection Glib::SignalTimeout::connect(const sigc::slot&lt;bool&gt;&amp; slot,
                                      unsigned int interval, int priority = Glib::PRIORITY_DEFAULT);
</programlisting>
</para>

<para>Le premier paramètre est un objet <classname>slot</classname> appelé quand le délai est échu. Le deuxième argument est le nombre de millisecondes entre chaque appel de la fonction. Vous recevez en retour un objet <classname>sigc::connection</classname> qu'il est possible d'utiliser pour désactiver la connexion à l'aide de sa fonction membre <methodname>disconnect()</methodname> :</para>

<para>

<programlisting>
my_connection.disconnect();
</programlisting>
</para>

<para lang="en">
Another way of destroying the connection is your signal handler.
It has to be of the type <classname>sigc::slot&lt;bool&gt;</classname>.
As you see from the definition your signal handler has to return a value of
the type <literal>bool</literal>. A definition of a sample method might
look like this:

<programlisting lang="en">
bool MyCallback() { std::cout &lt;&lt; "Hello World!\n" &lt;&lt; std::endl; return true; }
</programlisting>

</para>

<para>Vous pouvez arrêter l'appel périodique de la fonction en renvoyant <literal>false</literal> à partir du gestionnaire de signal. Mais si vous voulez que la fonction soit réitérée, il faut qu'elle renvoie <literal>true</literal>.</para>

<para>Voici un exemple de cette technique :</para>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/timeout/?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>timerexample.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLE_TIMEREXAMPLE_H
#define GTKMM_EXAMPLE_TIMEREXAMPLE_H

#include &lt;gtkmm.h&gt;
#include &lt;iostream&gt;
#include &lt;map&gt;

class TimerExample : public Gtk::Window
{
public:
  TimerExample();

protected:
  // signal handlers
  void on_button_add_timer();
  void on_button_delete_timer();
  void on_button_quit();

  // This is the callback function the timeout will call
  bool on_timeout(int timer_number);

  // Member data:

  Gtk::Box m_Box;
  Gtk::Button m_ButtonAddTimer, m_ButtonDeleteTimer, m_ButtonQuit;

  // Keep track of the timers being added:
  int m_timer_number;

  // These two constants are initialized in the constructor's member initializer:
  const int count_value;
  const int timeout_value;

  // STL map for storing our connections
  std::map&lt;int, sigc::connection&gt; m_timers;

  // STL map for storing our timer values.
  // Each timer counts back from COUNT_VALUE to 0 and is removed when it reaches 0
  std::map&lt;int, int&gt; m_counters;
};

#endif // GTKMM_EXAMPLE_TIMEREXAMPLE_H
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "timerexample.h"
#include &lt;gtkmm/application.h&gt;

int main (int argc, char *argv[])
{
  auto app = Gtk::Application::create(argc, argv, "org.gtkmm.example");

  TimerExample example;
  return app-&gt;run(example);
}
</programlisting>
<para lang="en">File: <filename>timerexample.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "timerexample.h"

TimerExample::TimerExample() :
  m_Box(Gtk::ORIENTATION_HORIZONTAL, 10),
  m_ButtonAddTimer("_Add", true),
  m_ButtonDeleteTimer("_Remove", true),
  m_ButtonQuit("_Quit", true),
  m_timer_number(0), // start numbering the timers at 0
  count_value(5), // each timer will count down 5 times before disconnecting
  timeout_value(1500) // 1500 ms = 1.5 seconds
{
  set_border_width(10);

  add(m_Box);
  m_Box.pack_start(m_ButtonAddTimer);
  m_Box.pack_start(m_ButtonDeleteTimer);
  m_Box.pack_start(m_ButtonQuit);

  // Connect the three buttons:
  m_ButtonQuit.signal_clicked().connect(sigc::mem_fun(*this,
              &amp;TimerExample::on_button_quit));
  m_ButtonAddTimer.signal_clicked().connect(sigc::mem_fun(*this,
              &amp;TimerExample::on_button_add_timer));
  m_ButtonDeleteTimer.signal_clicked().connect(sigc::mem_fun(*this,
              &amp;TimerExample::on_button_delete_timer));

  show_all_children();
}

void TimerExample::on_button_quit()
{
  hide();
}

void TimerExample::on_button_add_timer()
{
  // Creation of a new object prevents long lines and shows us a little
  // how slots work.  We have 0 parameters and bool as a return value
  // after calling sigc::bind.
  sigc::slot&lt;bool&gt; my_slot = sigc::bind(sigc::mem_fun(*this,
              &amp;TimerExample::on_timeout), m_timer_number);

  // This is where we connect the slot to the Glib::signal_timeout()
  sigc::connection conn = Glib::signal_timeout().connect(my_slot,
          timeout_value);

  // Remember the connection:
  m_timers[m_timer_number] = conn;

  // Initialize timer count:
  m_counters[m_timer_number] = count_value + 1;

  // Print some info to the console for the user:
  std::cout &lt;&lt; "added timeout " &lt;&lt; m_timer_number++ &lt;&lt; std::endl;
}

void TimerExample::on_button_delete_timer()
{
  // any timers?
  if(m_timers.empty())
  {
    // no timers left
    std::cout &lt;&lt; "Sorry, there are no timers left." &lt;&lt; std::endl;
  }
  else
  {
    // get the number of the first timer
    int timer_number = m_timers.begin()-&gt;first;

    // Give some info to the user:
    std::cout &lt;&lt; "manually disconnecting timer " &lt;&lt; timer_number
        &lt;&lt; std::endl;

    // Remove the entry in the counter values
    m_counters.erase(timer_number);

    // Diconnect the signal handler:
    m_timers[timer_number].disconnect();

    // Forget the connection:
    m_timers.erase(timer_number);
  }
}

bool TimerExample::on_timeout(int timer_number)
{
  // Print the timer:
  std::cout &lt;&lt; "This is timer " &lt;&lt; timer_number;

  // decrement and check counter value
  if (--m_counters[timer_number] == 0)
  {
    std::cout &lt;&lt; " being disconnected" &lt;&lt;  std::endl;

    // delete the counter entry in the STL MAP
    m_counters.erase(timer_number);

    // delete the connection entry in the STL MAP
    m_timers.erase(timer_number);

    // Note that we do not have to explicitly call disconnect() on the
    // connection since Gtk::Main does this for us when we return false.
    return false;
  }

  // Print the timer value
  std::cout &lt;&lt; " - " &lt;&lt; m_counters[timer_number] &lt;&lt; "/"
      &lt;&lt; count_value &lt;&lt; std::endl;

 // Keep going (do not disconnect yet):
  return true;
}
</programlisting>
<!-- end inserted example code -->

</sect1>

<sect1 id="sec-monitoring-io">
<title>Fonctions de contrôle des entrées/sorties</title>

<para>Une des caractéristiques intéressantes de GLib (une des bibliothèques sous-jacentes à <application>gtkmm</application>) est la possibilité de demander la vérification des données d'un descripteur de fichier à votre intention. La chose est particulièrement utile pour les applications réseau. Pour cette vérification, vous utilisez la fonction membre :</para>

<para>
<programlisting lang="en">
sigc::connection Glib::SignalIO::connect(const sigc::slot&lt;bool,Glib::IOCondition&gt;&amp; slot,
                                 int fd, Glib::IOCondition condition,
                                 int priority = Glib::PRIORITY_DEFAULT);
</programlisting>
</para>

<para lang="en">
The first argument is a slot you wish to have called when
the specified event (see argument 3) occurs on the file descriptor you specify
using argument two. Argument three may be one or more (using
<literal>|</literal>) of:
</para>

<itemizedlist>
<listitem>

<para>Glib::IO_IN - appelle la fonction membre quand il y a des données prêtes en lecture dans le descripteur de fichier.</para>
</listitem>
<listitem>

<para>Glib::IO_OUT - appelle la fonction membre quand le descripteur de fichier est prêt pour l'écriture.</para>
</listitem>
<listitem>

<para>Glib::IO_PRI - appelle la fonction membre quand le descripteur de fichier a des données à lire d'urgence.</para>
</listitem>
<listitem>

<para>Glib::IO_ERR - appelle la fonction membre quand une erreur est arrivée sur le descripteur de fichier.</para>
</listitem>
<listitem>

<para>Glib::IO_HUP - appelle la fonction membre quand il y a une interruption (la connexion a été interrompue généralement pour les tubes et les connecteurs).</para>
</listitem>

</itemizedlist>

<para>La valeur de retour qui est du type <classname>sigc::connection</classname> peut être utilisée pour arrêter le contrôle sur ce descripteur de fichier avec la fonction membre <methodname>disconnect()</methodname>. Le gestionnaire de signal de <parameter>slot</parameter> doit être déclaré comme suit :</para>

<para>
<programlisting>
bool input_callback(Glib::IOCondition condition);
</programlisting>
</para>

<para lang="en">
where <parameter>condition</parameter> is as
specified above. As usual the slot is created with
<function>sigc::mem_fun()</function> (for a member method of an object), or
<function>sigc::ptr_fun()</function> (for a function).
</para>

<para>Un petit exemple suit. Pour vous servir de cet exemple, lancez-le à partir d'un terminal ; il ne crée pas de fenêtre. Il va créer un tube nommé <literal>testfifo</literal> dans le répertoire actuel. Puis, lancez un autre instance de terminal et saisissez <literal>echo "Hello" &gt; testfifo</literal>. Le terminal de l'exemple affiche chaque ligne saisie dans l'autre instance jusqu'à ce que vous saisissiez <literal>echo "Q" &gt; testfifo</literal>.</para>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/input/?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include &lt;build/config.h&gt;
#include &lt;gtkmm/application.h&gt;
#include &lt;glibmm/main.h&gt;
#include &lt;glibmm/iochannel.h&gt;
#include &lt;fcntl.h&gt;
#include &lt;iostream&gt;

#include &lt;unistd.h&gt; //The SUN Forte compiler puts F_OK here.

//The SUN Forte compiler needs these for mkfifo:
#include &lt;sys/types.h&gt;
#include &lt;sys/stat.h&gt;

Glib::RefPtr&lt;Gtk::Application&gt; app;

int read_fd;
Glib::RefPtr&lt;Glib::IOChannel&gt; iochannel;

/*
  send to the fifo with:
  echo "Hello" &gt; testfifo

  quit the program with:
  echo "Q" &gt; testfifo
*/

// this will be our signal handler for read operations
// it will print out the message sent to the fifo
// and quit the program if the message was 'Q'.
bool MyCallback(Glib::IOCondition io_condition)
{
  if ((io_condition &amp; Glib::IO_IN) == 0) {
    std::cerr &lt;&lt; "Invalid fifo response" &lt;&lt; std::endl;
  }
  else {
   Glib::ustring buf;

   iochannel-&gt;read_line(buf);
   std::cout &lt;&lt; buf;
   if (buf == "Q\n")
     app-&gt;quit();

  }
  return true;
}


int main(int argc, char *argv[])
{
  app = Gtk::Application::create(argc, argv, "org.gtkmm.example");

  if (access("testfifo", F_OK) == -1) {
    // fifo doesn't exist - create it
    #ifdef HAVE_MKFIFO
    if (mkfifo("testfifo", 0666) != 0) {
      std::cerr &lt;&lt; "error creating fifo" &lt;&lt; std::endl;
      return -1;
    }
    #else
      std::cerr &lt;&lt; "error creating fifo: This platform does not have mkfifo()"
          &lt;&lt; std::endl;
    #endif //HAVE_MKFIFO
  }

  // Although we will only read from the fifo, we open it in read/write mode.
  // Due to a peculiarity with the poll() system call, used deep down in glib,
  // this small program will use all available CPU time, if the fifo is opened
  // as O_RDONLY. See a discussion on the gtkmm-list, e.g.
  // https://mail.gnome.org/archives/gtkmm-list/2015-September/msg00034.html
  // and the link from there to stackoverflow.
  read_fd = open("testfifo", O_RDWR);
  if (read_fd == -1)
  {
    std::cerr &lt;&lt; "error opening fifo" &lt;&lt; std::endl;
    return -1;
  }

  // connect the signal handler
  Glib::signal_io().connect(sigc::ptr_fun(MyCallback), read_fd, Glib::IO_IN);

  // Creates a iochannel from the file descriptor
  iochannel = Glib::IOChannel::create_from_fd(read_fd);

  // and last but not least - run the application main loop
  app-&gt;hold(); // keep the application running without a window
  app-&gt;run();

  // now remove the temporary fifo
  if(unlink("testfifo"))
    std::cerr &lt;&lt; "error removing fifo" &lt;&lt; std::endl;

  return 0;
}
</programlisting>
<!-- end inserted example code -->

</sect1>

<sect1 id="sec-idle-functions">
<title>Fonctions de temporisation</title>

<para>Si vous voulez définir une fonction membre appelée quand il n'y aucune autre activité en cours, utilisez :</para>

<para>
<programlisting lang="en">
sigc::connection  Glib::SignalIdle::connect(const sigc::slot&lt;bool&gt;&amp; slot,
                                    int priority = Glib::PRIORITY_DEFAULT_IDLE);
</programlisting>
</para>

<para>Cela demande à <application>gtkmm</application> d'appeler la fonction membre indiquée chaque fois qu'il ne se passe rien d'autre. Vous pouvez définir une priorité (les plus petits nombres correspondent aux priorités les plus élevées). Il y a deux manières de déconnecter le gestionnaire de signal : par l'appel de la fonction membre <methodname>disconnect()</methodname> sur l'objet <classname>sigc::connection</classname> ou en renvoyant <literal>false</literal> dans le gestionnaire du signal, qui doit être déclaré ainsi :</para>

<para>
<programlisting>
bool idleFunc();
</programlisting>
</para>

<para>Comme ceci est tout à fait semblable aux fonctions membres des paragraphes précédents, cette explication doit être suffisante pour comprendre comment cela se passe. Toutefois, voici un petit exemple :</para>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/idle/?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>idleexample.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLE_IDLEEXAMPLE_H
#define GTKMM_EXAMPLE_IDLEEXAMPLE_H

#include &lt;gtkmm.h&gt;
#include &lt;iostream&gt;

class IdleExample : public Gtk::Window
{
public:
  IdleExample();

protected:
  // Signal Handlers:
  bool on_timer();
  bool on_idle();
  void on_button_clicked();

  // Member data:
  Gtk::Box m_Box;
  Gtk::Button m_ButtonQuit;
  Gtk::ProgressBar m_ProgressBar_c;
  Gtk::ProgressBar m_ProgressBar_d;
};

#endif // GTKMM_EXAMPLE_IDLEEXAMPLE_H
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "idleexample.h"
#include &lt;gtkmm/application.h&gt;

int main (int argc, char *argv[])
{
  auto app = Gtk::Application::create(argc, argv, "org.gtkmm.example");

  IdleExample example;
  return app-&gt;run(example);
}
</programlisting>
<para lang="en">File: <filename>idleexample.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "idleexample.h"

IdleExample::IdleExample() :
  m_Box(Gtk::ORIENTATION_VERTICAL, 5),
  m_ButtonQuit("_Quit", true)
{
  set_border_width(5);

  // Put buttons into container

  // Adding a few widgets:
  add(m_Box);
  m_Box.pack_start( *Gtk::manage(new Gtk::Label("Formatting Windows drive C:")));
  m_Box.pack_start( *Gtk::manage(new Gtk::Label("100 MB")) );
  m_Box.pack_start(m_ProgressBar_c);

  m_Box.pack_start( *Gtk::manage(new Gtk::Label("")) );

  m_Box.pack_start( *Gtk::manage(new Gtk::Label("Formatting Windows drive D:")));
  m_Box.pack_start( *Gtk::manage(new Gtk::Label("5000 MB")) );
  m_Box.pack_start(m_ProgressBar_d);

  auto hbox = Gtk::manage( new Gtk::Box(Gtk::ORIENTATION_HORIZONTAL,10));
  m_Box.pack_start(*hbox);
  hbox-&gt;pack_start(m_ButtonQuit, Gtk::PACK_EXPAND_PADDING);

  // Connect the signal handlers:
  m_ButtonQuit.signal_clicked().connect( sigc::mem_fun(*this,
              &amp;IdleExample::on_button_clicked) );

  // formatting drive c in timeout signal handler - called once every 50ms
  Glib::signal_timeout().connect( sigc::mem_fun(*this, &amp;IdleExample::on_timer),
          50 );

  // formatting drive d in idle signal handler - called as quickly as possible
  Glib::signal_idle().connect( sigc::mem_fun(*this, &amp;IdleExample::on_idle) );

  show_all_children();
}


void IdleExample::on_button_clicked()
{
  hide();
}

// this timer callback function is executed once every 50ms (set in connection
// above).  Use timeouts when speed is not critical. (ie periodically updating
// something).
bool IdleExample::on_timer()
{
  double value = m_ProgressBar_c.get_fraction();

  // Update progressbar 1/500th each time:
  m_ProgressBar_c.set_fraction(value + 0.002);

  return value &lt; 0.99;  // return false when done
}


// This idle callback function is executed as often as possible, hence it is
// ideal for processing intensive tasks.
bool IdleExample::on_idle()
{
  double value = m_ProgressBar_d.get_fraction();

  // Update progressbar 1/5000th each time:
  m_ProgressBar_d.set_fraction(value + 0.0002);

  return value &lt; 0.99;  // return false when done
}
</programlisting>
<!-- end inserted example code -->

<para>Cet exemple souligne la différence entre fonctions membres de temporisation et fonctions membres à délai échu. Si vous avez besoin de fonctions appelées périodiquement et que la rapidité n'a pas grosse importance, alors servez-vous des fonctions membres à délai échu. Si vous voulez des fonctions membres appelées aussi souvent que possible (comme des fonctions membres de calcul de fractales en arrière-plan), alors utilisez les fonctions membres de temporisation.</para>

<para>Essayez d'exécuter l'exemple tout en augmentant la charge de votre système. La barre de progression supérieure doit avancer régulièrement ; l'inférieure devrait ralentir.</para>

</sect1>

</chapter>

<chapter id="chapter-memory">
<title>Gestion de la mémoire</title>

<sect1 id="sec-memory-widgets">
<title>Éléments graphiques</title>

<sect2 id="memory-normal">
<title>Gestion classique de la mémoire en C++</title>

<para><application>gtkmm</application> autorise le programmeur à contrôler la durée de vie (c'est-à-dire, la construction et la destruction) de tout élément graphique de la même manière que celle de n'importe quel objet C++. Cette polyvalence autorise, soit l'utilisation des opérateurs <literal>new</literal> et <literal>delete</literal> pour créer et détruire les objets de manière dynamique, soit l'utilisation de données membres de classes régulières (qui sont détruites automatiquement quand la classe est détruite), soit l'utilisation d'instances locales (qui sont détruites dès que l'instance est hors de portée). Certaines boîtes à outils GUI C++ n'offrent pas cette souplesse : elles restreignent le programmeur à un sous-ensemble des fonctionnalités de gestion mémoire du C++.</para>

<para>Voici quelques exemples de gestion traditionnelle de la mémoire en C++ :</para>

<sect3 id="memory-class-scope">
<title>Éléments graphiques à portée de classe</title>

<para>Si un programmeur n'a pas besoin d'allocation dynamique de mémoire, il peut se servir d'éléments graphiques automatiques à portée de classe. Un des avantages des éléments graphiques automatiques à portée de classe est que la gestion de la mémoire est regroupée en un seul endroit. Le programmeur ne risque pas de fuites de mémoire en oubliant un <literal>delete</literal> sur un élément graphique.</para>

<para lang="en">
The primary disadvantage of using class scope widgets is revealing
the class implementation rather than the class interface in the class header.
</para>

<para>
<programlisting lang="en">
#include &lt;gtkmm/button.h&gt;
#include &lt;gtkmm/window.h&gt;
class Foo : public Gtk::Window
{
private:
  Gtk::Button theButton;
  // will be destroyed when the Foo object is destroyed
};
</programlisting>
</para>
</sect3>

<sect3 id="memory-function-scope">
<title>Éléments graphiques à portée de fonction</title>

<para lang="en">
If a programmer does not need a class scope widget, a function scope widget
may also be used. The advantages to function scope over class scope are the
increased data hiding and reduced dependencies.
<programlisting lang="en">
{
  Gtk::Button aButton;
  aButton.show();
  ...
  app-&gt;run();
}
</programlisting>
</para>
</sect3>

<sect3 id="memory-dynamic-allocation">
<title>Allocation dynamique avec new et delete</title>

<para lang="en">
Although, in most cases, the programmer will prefer to allow containers to
automatically destroy their children using <function>Gtk::manage()</function> (see
below), the programmer is not required to use <function>Gtk::manage()</function>.
The traditional <literal>new</literal> and <literal>delete</literal> operators
may also be used.
<programlisting lang="en">
Gtk::Button* pButton = new Gtk::Button("Test");

// do something useful with pButton

delete pButton;
</programlisting>
Here, the programmer deletes <varname>pButton</varname> to prevent a memory leak.
</para>
</sect3>

</sect2>

<sect2 id="memory-managed-widgets">
<title>Éléments graphiques gérés</title>

<para lang="en">
Alternatively, you can let a widget's container control when the widget is
destroyed. In most cases, you want a widget to last only as long as the
container it is in. To delegate the management of a widget's lifetime to its
container, first create it with <function>Gtk::manage()</function> and
pack it into its container with <methodname>Gtk::Container::add()</methodname>,
<methodname>Gtk::Box::pack_start()</methodname>, or a similar method. Now the
widget will be destroyed whenever its container is destroyed.
</para>

<sect3 id="memory-managed-dynamic">
<title>Allocation dynamique avec manage() et add()</title>

<para lang="en">
<application>gtkmm</application> provides the <function>manage()</function> function and
<methodname>add()</methodname> methods to create and destroy widgets. Every widget
except a top-level window must be added or packed into a container in order to
be displayed. The <function>manage()</function> function marks a widget
so that when the widget is added to a container, the container becomes
responsible for deleting the widget.
</para>

<para lang="en">
<programlisting lang="en">
MyContainer::MyContainer()
{
  Gtk::Button* pButton = Gtk::manage(new Gtk::Button("Test"));
  add(*pButton); //add *pButton to MyContainer
}
</programlisting>
Now, when objects of type <classname>MyContainer</classname> are destroyed, the
button will also be deleted. It is no longer necessary to delete <varname>pButton</varname>
to free the button's memory; its deletion has been delegated to the
<classname>MyContainer</classname> object.
</para>

<para lang="en">
Of course, a top-level container will not be added to another container. The
programmer is responsible for destroying the top-level container using one of
the traditional C++ techniques. For instance, your top-level Window might just
be an instance in your <function>main()</function> function.
</para>

</sect3>
</sect2>
</sect1>

<sect1 id="sec-memory-shared-resources">
<title>Ressources partagées</title>

<para lang="en">
Some objects, such as <classname>Gdk::Pixbuf</classname>s and
<classname>Pango::Font</classname>s, are obtained from a shared store.
Therefore you cannot instantiate your own instances. These classes typically
inherit from <classname>Glib::Object</classname>. Rather than requiring you to
reference and unreference these objects, <application>gtkmm</application> uses the
<classname>Glib::RefPtr&lt;&gt;</classname> smartpointer. Cairomm has its own
smartpointer, <classname>Cairo::RefPtr&lt;&gt;</classname>.
</para>

<para lang="en">
Objects such as <classname>Gdk::Pixbuf</classname> can only be instantiated
with a <methodname>create()</methodname> function. For instance,
<programlisting lang="en">
Glib::RefPtr&lt;Gdk::Pixbuf&gt; pixbuf = Gdk::Pixbuf::create_from_file(filename);
</programlisting>
</para>

<para lang="en">
You have no way of getting a bare <classname>Gdk::Pixbuf</classname>. In the
example, <varname>pixbuf</varname> is a smart pointer, so you can do this, much
like a normal pointer:
<programlisting lang="en">
int width = 0;
if(pixbuf)
{
  width = pixbuf-&gt;get_width();
}
</programlisting>
</para>

<para lang="en">
When <varname>pixbuf</varname> goes out of scope an
<methodname>unref()</methodname> will happen in the background and you don't need
to worry about it anymore. There's no <literal>new</literal> so there's no
<literal>delete</literal>.
</para>
<para lang="en">
If you copy a <classname>RefPtr</classname>, for instance
<programlisting lang="en">
Glib::RefPtr&lt;Gdk::Pixbuf&gt; pixbuf2 = pixbuf;
</programlisting>
, or if you pass it as a method argument or a return type, then
<classname>RefPtr</classname> will do any necessary referencing to ensure that
the instance will not be destroyed until the last <classname>RefPtr</classname>
has gone out of scope.
</para>
<para>Consultez cette <link linkend="chapter-refptr">annexe</link> pour une information détaillée concernant les RefPtr.</para>
<para lang="en">
If you wish to learn more about smartpointers, you might look in these
books:
<itemizedlist>
<listitem><para lang="en">
Bjarne Stroustrup, "The C++ Programming Language" Forth Edition - section 34.3
</para></listitem>
<listitem><para lang="en">
Nicolai M. Josuttis, "The C++ Standard Library" - section 4.2
</para></listitem>
</itemizedlist>
</para>

</sect1>

</chapter>

<chapter id="chapter-builder">
<title>Glade et Gtk::Builder</title>
<para>Même si vous pouvez utiliser du code C++ pour instancier et disposer les éléments graphiques, cela devient vite répétitif et fastidieux. De plus, il est nécessaire de compiler à nouveau pour voir les modifications. L'application <application>Glade</application> vous permet de disposer les éléments graphiques à l'écran et d'enregistrer une description XML de l'arrangement. Votre application peut alors utiliser l'API <application>Gtk::Builder</application> pour charger ce fichier XML au lancement de l'application et obtenir un pointeur sur les instances de l'élément graphique précisément désigné.</para>

<para lang="en">
This has the following advantages:
<orderedlist>
<listitem><simpara lang="en">Less C++ code is required.</simpara></listitem>
<listitem><simpara lang="en">UI changes can be seen more quickly, so UIs are able to improve.</simpara></listitem>
<listitem><simpara lang="en">Designers without programming skills can create and edit UIs.</simpara></listitem>
</orderedlist>
</para>

<para>Vous aurez encore besoin de code C++ pour gérer les transactions sur l'interface déclenchées par les actions de l'utilisateur, mais l'utilisation de <application>Gtk::Builder</application> pour la disposition des éléments graphiques vous permet de vous concentrer sur l'implémentation des fonctionnalités.</para>

<sect1 id="sec-builder-loading-glade-file">
<title>Chargement du fichier .glade</title>
<para lang="en">
<classname>Gtk::Builder</classname> must be used via a
<classname>Glib::RefPtr</classname>. Like all such classes, you need to use a
<methodname>create()</methodname> method to instantiate it. For instance,
<programlisting lang="en">
Glib::RefPtr&lt;Gtk::Builder&gt; builder = Gtk::Builder::create_from_file("basic.glade");
</programlisting>
This will instantiate the windows defined in the .glade file, though they will
not be shown immediately unless you have specified that via the <guilabel>Properties</guilabel>
window in <application>Glade</application>.
</para>

<para lang="en">To instantiate just one window, or just one of the child widgets, you can specify the name of a widget as the second parameter. For instance,
<programlisting lang="en">
Glib::RefPtr&lt;Gtk::Builder&gt; builder = Gtk::Builder::create_from_file("basic.glade", "treeview_products");
</programlisting>
</para>

</sect1>

<sect1 id="sec-builder-accessing-widgets">
<title>Accès aux éléments graphiques</title>

<para lang="en">
To access a widget, for instance to <methodname>show()</methodname> a dialog, use
the <methodname>get_widget()</methodname> method, providing the widget's name. This
name should be specified in the <application>Glade</application> Properties
window. If the widget could not be found, or is of the wrong type, then the
pointer will be set to nullptr.
<programlisting lang="en">
Gtk::Dialog* pDialog = nullptr;
builder-&gt;get_widget("DialogBasic", pDialog);
</programlisting>
</para>

<para><application>Gtk::Builder</application> vérifie qu'il ne s'agit pas d'un pointeur NULL et que l'élément graphique est du type attendu ; il affiche des avertissements sur la ligne de commande s'il y a de telles anomalies.</para>

<para>Souvenez-vous que <methodname>get_widget()</methodname> ne crée pas un nouvel exemplaire d'élément graphique ; avec cette fonction, vous obtenez simplement un pointeur sur un élément graphique qui existe déjà. Vous obtenez toujours un pointeur sur le même élément graphique quand vous appelez <methodname>get_widget()</methodname> sur le même <classname>Gtk::Builder</classname>, avec le même nom d'élément graphique. Les éléments graphiques sont créés pendant l'appel à <methodname>Gtk::Builder::create_from_file()</methodname>.</para>

<para><methodname>get_widget()</methodname> renvoie des éléments graphiques enfants marqués (voir le chapitre sur la <link linkend="chapter-memory">Gestion de la mémoire</link>) par la fonction <function>manage()</function> ; ils seront donc détruits quand leur conteneur parent sera détruit. Donc, si vous n'obtenez qu'un seul élément graphique de <application>Gtk::Builder</application>, au lieu de la totalité de la fenêtre, alors vous devez, soit le placer dans un objet <classname>Container</classname>, soit le détruire. Les objets <classname>Windows</classname> (tout comme les objets <classname>Dialogs</classname>) ne peuvent pas être gérés étant donné qu'ils n'ont pas de conteneur parent ; vous devez donc les détruire à un moment donné.</para>

<sect2 id="builder-example-loading">
<title>Exemple</title>
<para>Cet exemple simple montre comment charger un fichier <application>Glade</application> au cours de l'exécution et accéder aux éléments graphiques avec <application>Gtk::Builder</application>.</para>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/builder/basic?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include &lt;gtkmm.h&gt;
#include &lt;iostream&gt;

Gtk::Dialog* pDialog = nullptr;

static
void on_button_clicked()
{
  if(pDialog)
    pDialog-&gt;hide(); //hide() will cause main::run() to end.
}

int main (int argc, char **argv)
{
  auto app = Gtk::Application::create(argc, argv, "org.gtkmm.example");

  //Load the GtkBuilder file and instantiate its widgets:
  auto refBuilder = Gtk::Builder::create();
  try
  {
    refBuilder-&gt;add_from_file("basic.glade");
  }
  catch(const Glib::FileError&amp; ex)
  {
    std::cerr &lt;&lt; "FileError: " &lt;&lt; ex.what() &lt;&lt; std::endl;
    return 1;
  }
  catch(const Glib::MarkupError&amp; ex)
  {
    std::cerr &lt;&lt; "MarkupError: " &lt;&lt; ex.what() &lt;&lt; std::endl;
    return 1;
  }
  catch(const Gtk::BuilderError&amp; ex)
  {
    std::cerr &lt;&lt; "BuilderError: " &lt;&lt; ex.what() &lt;&lt; std::endl;
    return 1;
  }

  //Get the GtkBuilder-instantiated Dialog:
  refBuilder-&gt;get_widget("DialogBasic", pDialog);
  if(pDialog)
  {
    //Get the GtkBuilder-instantiated Button, and connect a signal handler:
    Gtk::Button* pButton = nullptr;
    refBuilder-&gt;get_widget("quit_button", pButton);
    if(pButton)
    {
      pButton-&gt;signal_clicked().connect( sigc::ptr_fun(on_button_clicked) );
    }

    app-&gt;run(*pDialog);
  }

  delete pDialog;

  return 0;
}
</programlisting>
<!-- end inserted example code -->

</sect2>

</sect1>


<sect1 id="sec-builder-using-derived-widgets">
<title>Utilisation d'éléments graphiques dérivés</title>
<para>Vous pouvez utilisez <application>Glade</application> pour placer vos propres éléments graphiques personnalisés, dérivés à partir d'une classe d'élément graphique <application>gtkmm</application>. Vous pouvez ainsi conserver votre code organisé et encapsulé. Bien entendu, vous ne voyez pas l'aspect exact et les propriétés de l'élément graphique dérivé dans <application>Glade</application>, mais vous pouvez indiquer son emplacement, ses éléments graphiques enfants et les propriétés de la classe <application>gtkmm</application> de base.</para>

<para lang="en">Use <methodname>Gtk::Builder::get_widget_derived()</methodname> like so:
<programlisting lang="en">
DerivedDialog* pDialog = nullptr;
builder-&gt;get_widget_derived("DialogBasic", pDialog);
</programlisting>
</para>

<para>Votre classe dérivée doit avoir un constructeur prenant comme paramètre un pointeur sur le type C sous-jacent et l'instance de <classname>Gtk::Builder</classname>. Toutes les classes <application>gtkmm</application> en rapport définissent leurs types C sous-jacents en tant qu'objets <classname>BaseObjectType</classname> (par exemple <classname>Gtk::Dialog</classname> défini son type <classname>BaseObjectType</classname> comme <literal>GtkDialog</literal>).</para>
<para lang="en">
You must call the base class's constructor in the initialization list, providing the C pointer. For
instance,
<programlisting lang="en">
DerivedDialog::DerivedDialog(BaseObjectType* cobject, const Glib::RefPtr&lt;Gtk::Builder&gt;&amp; builder)
: Gtk::Dialog(cobject)
{
}
</programlisting>
</para>

<para lang="en">
You could then encapsulate the manipulation of the child widgets in the
constructor of the derived class, maybe using <methodname>get_widget()</methodname>
or <methodname>get_widget_derived()</methodname> again. For instance,
<programlisting lang="en">
DerivedDialog::DerivedDialog(BaseObjectType* cobject, const Glib::RefPtr&lt;Gtk::Builder&gt;&amp; builder)
: Gtk::Dialog(cobject),
  m_builder(builder),
  m_pButton(nullptr)
{
  //Get the Glade-instantiated Button, and connect a signal handler:
  m_builder-&gt;get_widget("quit_button", m_pButton);
  if(m_pButton)
  {
    m_pButton-&gt;signal_clicked().connect( sigc::mem_fun(*this, &amp;DerivedDialog::on_button_quit) );
  }
}
</programlisting>
</para>

<para lang="en">
Starting with <application>gtkmm</application> 3.19.7, it's possible to pass additional arguments from
<methodname>get_widget_derived()</methodname> to the constructor of the derived
widget. For instance, this call to <methodname>get_widget_derived()</methodname>
<programlisting lang="en">
<![CDATA[DerivedDialog* pDialog = nullptr;
builder->get_widget_derived("DialogBasic", pDialog, true);]]>
</programlisting>
can invoke this constructor
<programlisting lang="en">
<![CDATA[DerivedDialog::DerivedDialog(BaseObjectType* cobject, const Glib::RefPtr<Gtk::Builder>& builder, bool warning)
: Gtk::Dialog(cobject),
  m_builder(builder),
  m_pButton(nullptr)
{
  // ....
}]]>
</programlisting>
</para>

<sect2 id="builder-example-accessing">
<title>Exemple</title>
<para>Cet exemple montre comment charger un fichier <application>Glade</application> au lancement et accéder aux éléments graphiques par l'intermédiaire d'une classe dérivée.</para>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/builder/derived?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>deriveddialog.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLE_DERIVED_DIALOG_H
#define GTKMM_EXAMPLE_DERIVED_DIALOG_H

#include &lt;gtkmm.h&gt;

class DerivedDialog : public Gtk::Dialog
{
public:
  DerivedDialog(BaseObjectType* cobject, const Glib::RefPtr&lt;Gtk::Builder&gt;&amp; refGlade);
  DerivedDialog(BaseObjectType* cobject, const Glib::RefPtr&lt;Gtk::Builder&gt;&amp; refGlade,
    bool is_glad);
  virtual ~DerivedDialog();

protected:
  //Signal handlers:
  void on_button_quit();

  Glib::RefPtr&lt;Gtk::Builder&gt; m_refGlade;
  Gtk::Button* m_pButton;
};

#endif //GTKMM_EXAMPLE_DERIVED_WINDOW_H
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "deriveddialog.h"
#include &lt;iostream&gt;
#include &lt;cstring&gt;

int main (int argc, char **argv)
{
  bool show_icon = false;
  bool is_glad = true;
  int argc1 = argc;
  if (argc &gt; 1)
  {
    if (std::strcmp(argv[1], "--glad") == 0)
    {
      show_icon = true;
      is_glad = true;
      argc1 = 1; // Don't give the command line arguments to Gtk::Application.
    }
    else if (std::strcmp(argv[1], "--sad") == 0)
    {
      show_icon = true;
      is_glad = false;
      argc1 = 1; // Don't give the command line arguments to Gtk::Application.
    }
  }

  auto app = Gtk::Application::create(argc1, argv, "org.gtkmm.example");

  //Load the Glade file and instantiate its widgets:
  auto refBuilder = Gtk::Builder::create();
  try
  {
    refBuilder-&gt;add_from_file("derived.glade");
  }
  catch(const Glib::FileError&amp; ex)
  {
    std::cerr &lt;&lt; "FileError: " &lt;&lt; ex.what() &lt;&lt; std::endl;
    return 1;
  }
  catch(const Glib::MarkupError&amp; ex)
  {
    std::cerr &lt;&lt; "MarkupError: " &lt;&lt; ex.what() &lt;&lt; std::endl;
    return 1;
  }
  catch(const Gtk::BuilderError&amp; ex)
  {
    std::cerr &lt;&lt; "BuilderError: " &lt;&lt; ex.what() &lt;&lt; std::endl;
    return 1;
  }

  //Get the GtkBuilder-instantiated dialog:
  DerivedDialog* pDialog = nullptr;
  if (show_icon)
    // This call to get_widget_derived() requires gtkmm 3.19.7 or higher.
    refBuilder-&gt;get_widget_derived("DialogDerived", pDialog, is_glad);
  else
    refBuilder-&gt;get_widget_derived("DialogDerived", pDialog);
  if(pDialog)
  {
    //Start:
    app-&gt;run(*pDialog);
  }

  delete pDialog;

  return 0;
}
</programlisting>
<para lang="en">File: <filename>deriveddialog.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "deriveddialog.h"

DerivedDialog::DerivedDialog(BaseObjectType* cobject, const Glib::RefPtr&lt;Gtk::Builder&gt;&amp; refGlade)
: Gtk::Dialog(cobject),
  m_refGlade(refGlade),
  m_pButton(nullptr)
{
  //Get the Glade-instantiated Button, and connect a signal handler:
  m_refGlade-&gt;get_widget("quit_button", m_pButton);
  if(m_pButton)
  {
    m_pButton-&gt;signal_clicked().connect( sigc::mem_fun(*this, &amp;DerivedDialog::on_button_quit) );
  }
}

// The first two parameters are mandatory in a constructor that will be called
// from Gtk::Builder::get_widget_derived().
// Additional parameters, if any, correspond to additional arguments in the call
// to Gtk::Builder::get_widget_derived().
DerivedDialog::DerivedDialog(BaseObjectType* cobject, const Glib::RefPtr&lt;Gtk::Builder&gt;&amp; refGlade,
  bool is_glad)
: DerivedDialog(cobject, refGlade) // Delegate to the other constructor
{
  // Show an icon.
  auto pImage = Gtk::manage(new Gtk::Image());
  pImage-&gt;set_from_icon_name(is_glad ? "face-smile" : "face-sad", Gtk::ICON_SIZE_DIALOG);
  pImage-&gt;show_all();
  get_content_area()-&gt;pack_start(*pImage);
}

DerivedDialog::~DerivedDialog()
{
}

void DerivedDialog::on_button_quit()
{
  hide(); //hide() will cause Gtk::Application::run() to end.
}
</programlisting>
<!-- end inserted example code -->

</sect2>

</sect1>

</chapter>

<chapter id="chapter-internationalization">
  <title>Internationalisation et adaptation locale</title>

  <para>Les applications <application>gtkmm</application> prennent facilement en charge plusieurs langues, y compris les langues non-européennes telles que le chinois et les langues s'écrivant de droite à gauche comme l'arabe. Une application <application>gtkmm</application> écrite et traduite de manière appropriée, utilise lors de son exécution la langue définie par l'environnement utilisateur.</para>
  <para>Vous ne devez pas anticiper le besoin de prendre en charge telles ou telles autres langues, mais vous ne devez jamais en exclure l'utilisation. De plus, il est plus facile de développer une application correctement dès le début que de l'améliorer après coup.</para>

  <para>Le processus consistant à écrire un code source autorisant la traduction s'appelle l'<literal>internationalisation</literal>, souvent abrégé en <literal>i18n</literal>. Le processus d'<literal>adaptation locale</literal> (localisation) quelquefois abrégé en <literal>l10n</literal>, met à disposition du texte, fondé sur ce code source, traduit dans d'autres langues.</para>

  <para>Le gros du travail dans le processus d'internationalisation est de rechercher les chaînes visibles par l'utilisateur et de les marquer comme traduisibles. Ce travail n'a pas besoin d'être réalisé en une seule fois - si vous réglez l'infrastructure du projet correctement, votre application fonctionnera normalement quel que soit le nombre de chaînes traîtées.</para>

  <para lang="en">
    String literals should be typed in the source code in English, but
    surrounded by a macro. The <application>gettext</application> (or intltool)
    utility can then extract the marked strings for translation, and substitute
    the translated text at runtime.
  </para>

  <sect1 id="sec-internationalization-intro">
    <title>Préparation du projet</title>

    <note>
      <para lang="en">
        In the instructions below we will assume that you will not be using
        <application>gettext</application> directly, but
        <application>intltool</application>, which was written specifically for
        <literal>GNOME</literal>. <application>intltool</application> uses
        <function>gettext()</function>, which extracts strings from source code,
        but <application>intltool</application> can also combine strings from
        other files, for example from desktop menu details, and GUI resource
        files such as <application>Glade</application> files, into standard
        <application>gettext</application> <filename>.pot/.po</filename> files.
      </para>
      <para lang="en">
        We also assume that you are using autotools (e.g.
        <application>automake</application> and
        <application>autoconf</application>) to build your project, and
        that you are using <ulink url="http://git.gnome.org/browse/gnome-common/tree/autogen.sh">
          <literal>./autogen.sh</literal> from
          <application>gnome-common</application></ulink>
        or a similar <literal>autogen.sh</literal> file, which, among other
        things, takes care of some <application>intltool</application>
        initialization.
      </para>
    </note>

    <para lang="en">
      An alternative to <application>gnome-common</application>'s
      <literal>autogen.sh</literal> may look like this:
    </para>
    <programlisting lang="en">#! /bin/sh -e
test -n "$srcdir" || srcdir=`dirname "$0"`
test -n "$srcdir" || srcdir=.

autoreconf --force --install --verbose --warnings=all "$srcdir"
echo "Running intltoolize --copy --force --automake"
intltoolize --copy --force --automake
test -n "$NOCONFIGURE" || "$srcdir/configure" "$@"</programlisting>

    <para>Créez un sous-répertoire nommé <literal>po</literal> dans le répertoire racine de votre projet. Ce répertoire contiendra en phase finale toutes les traductions. Dans celui-ci, créez un fichier nommé <literal>LINGUAS</literal> et un fichier nommé <literal>POTFILES.in</literal>. Il est aussi de pratique courante de créer un fichier <literal>ChangeLog</literal> dans le répertoire <literal>po</literal> pour que les traducteurs puissent garder trace des modifications de traduction.</para>

    <para><literal>LINGUAS</literal> contient une liste triée alphabétiquement des codes identifiant toutes les langues dans lesquelles votre programme est traduit (les lignes de commentaires débutant par <literal>#</literal> sont ignorées). Chaque code de langue listé dans <literal>LINGUAS</literal> doit avoir un fichier <literal>.po</literal> correspondant. Ainsi, si votre programme a des traductions en allemand et en japonais, le fichier <literal>LINGUAS</literal> ressemblera à :</para>
    <programlisting># keep this file sorted alphabetically, one language code per line
de
ja</programlisting>
    <para>(en outre, vous devez avoir dans le dossier <literal>po</literal> des fichiers <literal>ja.po</literal> et <literal>de.po</literal> contenant respectivement la traduction japonaise et allemande).</para>

    <para><literal>POTFILES.in</literal> est une liste des chemins vers tous les fichiers contenant des chaînes marquées pour la traduction, à partir du répertoire racine du projet. Ainsi, par exemple, si les sources du projet sont situées dans un sous-répertoire nommé <literal>src</literal> et si vous avez deux fichiers contenant des chaînes à traduire, votre fichier <literal>POTFILES.in</literal> ressemble à quelque chose comme :</para>

    <programlisting>src/main.cc
src/other.cc</programlisting>

    <para>Si vous utilisez <application>gettext</application> directement, vous ne pouvez marquer pour traduction que les chaînes situées dans les fichiers de code source. Mais, si vous vous servez de <application>intltool</application>, vous pouvez marquer des chaînes pour traduction dans divers autres formats de fichier, y compris les fichiers d'interface utilisateur <application>Glade</application>, xml, <ulink url="http://standards.freedesktop.org/desktop-entry-spec/latest/">.desktop</ulink> et de nombreux autres. Donc si vous avez conçu une partie des interfaces utilisateur du projet à l'aide de <application>Glade</application>, ajoutez également vos fichiers <filename>.glade</filename> dans la liste du fichier <literal>POTFILES.in</literal>.</para>

    <para>Maintenant que vous disposez d'un endroit où mettre vos traductions, il est nécessaire d'initialiser <application>intltool</application> et <application>gettext</application>. Ajoutez le code ci-après dans votre fichier <literal>configure.ac</literal>, en mettant le nom de votre programme à la place de « nom_programme » :</para>

    <programlisting lang="en">IT_PROG_INTLTOOL([0.35.0])

GETTEXT_PACKAGE=programname
AC_SUBST(GETTEXT_PACKAGE)
AC_DEFINE_UNQUOTED([GETTEXT_PACKAGE], ["$GETTEXT_PACKAGE"],
                   [The domain to use with gettext])
AM_GNU_GETTEXT([external])
AM_GNU_GETTEXT_VERSION([0.17])

PROGRAMNAME_LOCALEDIR=[${datadir}/locale]
AC_SUBST(PROGRAMNAME_LOCALEDIR)</programlisting>

    <para>La variable <varname>PROGRAMNAME_LOCALEDIR</varname> sera utilisée plus tard dans le fichier <literal>Makefile.am</literal> pour définir une macro utilisée quand vous initialisez <application>gettext</application> dans votre code source.</para>

    <para lang="en">
      <literal>AM_GLIB_GNU_GETTEXT</literal> has been an alternative to
      <literal>AM_GNU_GETTEXT</literal> and <literal>AM_GNU_GETTEXT_VERSION</literal>,
      but <literal>AM_GLIB_GNU_GETTEXT</literal> is now deprecated, and shall
      not be used in new code.
    </para>

    <para lang="en">
      In the top-level Makefile.am:
      <itemizedlist>
        <listitem>
          <para lang="en">Add <literal>po</literal> to the <literal>SUBDIRS</literal>
            variable. Without this, your translations won't get built and
            installed when you build the program</para>
        </listitem>
        <listitem>
          <para lang="en">
            Define <literal>INTLTOOL_FILES</literal> as:
            <programlisting lang="en">INTLTOOL_FILES = intltool-extract.in \
                 intltool-merge.in \
                 intltool-update.in</programlisting>
          </para>
        </listitem>
        <listitem>
          <para lang="en">
            Add <literal>INTLTOOL_FILES</literal> to the
            <literal>EXTRA_DIST</literal> list of files. This ensures that when
            you do a <command>make dist</command>, these commands will be
            included in the source tarball.
          </para>
        </listitem>
        <listitem>
          <para lang="en">
            Update your <literal>DISTCLEANFILES</literal>:
            <programlisting lang="en">DISTCLEANFILES = ... intltool-extract \
                 intltool-merge \
                 intltool-update \
                 po/.intltool-merge-cache</programlisting>
          </para>
        </listitem>
        <listitem>
          <para lang="en">
            Depending on the types of files that contain translatable strings,
            add code such as
            <programlisting lang="en">desktopdir = $(datadir)/applications
desktop_in_files = programname.desktop.in
desktop_DATA = $(desktop_in_files:.desktop.in=.desktop)
@INTLTOOL_DESKTOP_RULE@</programlisting>
          </para>
        </listitem>
      </itemizedlist>
    </para>

    <para>Dans votre <literal>src/Makefile.am</literal>, mettez à jour votre variable <literal>AM_CPPFLAGS</literal> en ajoutant la définition de macro préprocesseur suivante :</para>
    <programlisting>AM_CPPFLAGS = ... -DPROGRAMNAME_LOCALEDIR=\"${PROGRAMNAME_LOCALEDIR}\"</programlisting>
    <para>Cette macro sert quand vous initialisez <literal>gettext</literal> dans votre code source.</para>
  </sect1>

<sect1 id="sec-i18n-marking-strings">
  <title>Marquage des chaînes à traduire</title>

  <para>Les chaînes littérales doivent être saisies dans le code source en anglais, mais elles doivent être incorporées dans un appel à la fonction <function>gettext()</function>. Ces chaînes seront extraites pour traduction et les traductions utilisées lors de l'exécution au lieu des chaînes originelles en anglais.</para>

  <para>Le paquetage <application>GNU gettext</application> vous permet de marquer des chaînes dans le code source, de les extraire pour traduction et d'utiliser les chaînes traduites dans votre application.</para>

  <para lang="en">
    However, <application>Glib</application> defines
    <function>gettext()</function>
    support macros which are shorter wrappers in an easy-to-use form.
    To use these macros, include <literal>&lt;glibmm/i18n.h&gt;</literal>,
    and then, for example, substitute:
    <programlisting lang="en">display_message("Getting ready for i18n.");</programlisting>
    with:
    <programlisting lang="en">display_message(_("Getting ready for i18n."));</programlisting>
  </para>

  <para lang="en">
    For reference, it is possible to generate a file which contains all
    strings which appear in your code, even if they are not marked for translation,
    together with file name and line
    number references. To generate such a file named
    <literal>my-strings</literal>, execute the following command,
    within the source code directory:

    <programlisting lang="en">xgettext -a -o my-strings --omit-header *.cc *.h</programlisting>
  </para>

  <para lang="en">
    Finally, to let your program use the translation for the current locale,
    add this code to the beginning of your <filename>main.cc</filename> file, to initialize gettext.

<programlisting lang="en">bindtextdomain(GETTEXT_PACKAGE, PROGRAMNAME_LOCALEDIR);
bind_textdomain_codeset(GETTEXT_PACKAGE, "UTF-8");
textdomain(GETTEXT_PACKAGE);</programlisting>
  </para>

  <sect2 id="sec-i18n-gettext">
    <title>Comment fonctionne gettext</title>

    <para>Le script <application>intltool</application> / <application>xgettext</application> extrait les chaînes et les place dans un fichier <filename>mon_paquet.pot</filename>. Les traducteurs de votre application créent leur traduction en faisant d'abord une copie du fichier <filename>.pot</filename> dans un fichier <filename>nom_de_locale.po</filename>. Une « locale » identifie une langue et un codage pour cette langue, y compris les formats numériques et de date. Ultérieurement, si le texte de votre code source a été modifié, le script <literal>msmerge</literal> sera utilisé pour mettre à jour les fichiers <filename>nom_de_locale.po</filename> à partir d'une nouvelle génération du fichier <filename>.pot</filename>.</para>

    <para>Au moment de l'installation, les fichiers <filename>.po</filename> sont convertis dans un format binaire (avec l'extension <filename>.mo</filename>) et placés dans un répertoire système pour les fichiers d'environnement linguistique, par exemple <filename>/usr/share/locale/</filename>.</para>

    <para>Quand l'application est lancée, la bibliothèque <application>gettext</application> vérifie dans le répertoire système s'il y a un fichier <filename>.mo</filename> pour l'environnement linguistique de l'utilisateur (environnement que vous pouvez définir avec, par exemple, « export LANG=de_DE.UTF-8 » à partir d'un terminal). Puis, quand le programme atteint un appel <literal>gettext</literal>, il examine s'il existe une traduction pour la chaîne donnée. Si aucune n'est trouvée, la chaîne d'origine est utilisée.</para>
  </sect2>

  <sect2 id="sec-i18n-testing">
    <title>Vérification et ajout de traductions</title>

    <para lang="en">
      To convince yourself that you've done well, you may wish to add a
      translation for a new locale. In order to do that, go to the
      <filename>po</filename> subdirectory of your project and
      execute the following command:
      <programlisting lang="en">intltool-update --pot</programlisting>
    </para>

    <para>Cette commande crée un fichier nommé <filename>nom_du_programme.pot</filename>. Copiez ensuite ce fichier en lui donnant le nom <filename>code_langue.po</filename>, comme <filename>de.po</filename> ou <filename>hu.po</filename>. Ajoutez également ce code langue dans le fichier <literal>LINGUAS</literal>. Le fichier <filename>.po</filename> comporte un en-tête et une liste des chaînes en anglais, avec des emplacements pour les chaînes traduites à saisir. Assurez-vous que vous avez défini et utilisé <literal>UTF-8</literal> comme codage du fichier <filename>.po</filename> (comme défini dans l'en-tête, mais utilisé dans le contenu).</para>

    <!-- TODO: This need more explanation. What's the point of the fuzzy tag then? murrayc -->
    <note>
      <para>Il est possible que certaines chaînes soient marquées <literal>fuzzy</literal> (approximatives) dans le fichier <filename>.po</filename>. Les traductions ainsi marquées ne se substituent pas à la chaîne originelle. Pour qu'elles apparaissent, enlevez simplement la marque <literal>fuzzy</literal>.</para>
    </note>
  </sect2>

  <sect2 id="sec-i18n-resources">
    <title>Ressources</title>

    <para lang="en">
      More information about what lies behind the internationalization and localization process
      is presented and demonstrated in:

      <itemizedlist>
        <listitem>
          <para lang="en">
            <ulink url="https://wiki.gnome.org/TranslationProject/DevGuidelines">
              L10N Guidelines for Developers</ulink>
          </para>
        </listitem>

        <listitem>
          <para lang="en">
            <ulink url="http://bazaar.launchpad.net/~intltool/intltool/trunk/view/head:/README">Intltool README</ulink>
          </para>
        </listitem>

        <listitem>
          <para lang="en">
            <ulink url="https://wiki.gnome.org/TranslationProject/GitHowTo">How to use Git for GNOME translators</ulink>
          </para>
        </listitem>

        <listitem>
          <para lang="en">
            <ulink url="http://www.gnu.org/software/gettext/manual/gettext.html">gettext manual</ulink>
          </para>
        </listitem>

        <listitem>
          <para lang="en">
            <ulink url="http://ftp.gnome.org/pub/GNOME/sources/gtkmm_hello/"><literal>gtkmm_hello</literal> example package</ulink>
          </para>
        </listitem>

        <listitem>
          <para lang="en">
            <ulink url="http://ftp.gnome.org/pub/GNOME/sources/gnomemm_hello/"><literal>gnomemm_hello</literal> example package</ulink>
          </para>
        </listitem>
      </itemizedlist>
    </para>
  </sect2>

</sect1>

<sect1 id="sec-i18n-expecting-utf8">
<title>En attendant UTF8</title>
<para>Une application correctement internationalisée ne doit pas faire de suppositions sur le nombre d'octets par caractère. Cela signifie que vous ne devez pas faire d'arithmétique de pointeurs pour cheminer parmi les caractères d'une chaîne ; cela signifie aussi que vous ne devez pas vous servir d'objets <classname>std::string</classname> ou de fonctions C standard telles que <function>strlen()</function> car elle se fondent sur de telles suppositions pour effectuer leurs calculs.</para>
<para>Même si vous avez certainement déjà délaissé les tableaux de <literal>char*</literal> vides et l'arithmétique des pointeurs en vous servant de <classname>std::string</classname>, vous devez maintenant utiliser à la place des objets <classname>Glib::ustring</classname>. Voyez le chapitre concernant les <classname>Glib::ustring</classname> dans les <link linkend="sec-basics-ustring">Fondamentaux</link>.</para>

<sect2 id="i18n-ustring-iostreams"><title>Glib::ustring et std::iostreams</title>
<!-- <para>TODO: This section is not clear - it needs to spell things out more clearly and obviously.</para> -->
<para lang="en">
Unfortunately, the integration with the standard iostreams is not completely
foolproof. <application>gtkmm</application> converts <classname>Glib::ustring</classname>s to a
locale-specific encoding (which usually is not UTF-8) if you output them to an
<classname>ostream</classname> with <function>operator&lt;&lt;</function>.
Likewise, retrieving <classname>Glib::ustrings</classname> from
<classname>istream</classname> with <function>operator&gt;&gt;</function>
causes a conversion in the opposite direction. But this scheme breaks down if
you go through a <classname>std::string</classname>, e.g. by inputting text
from a stream to a <classname>std::string</classname> and then implicitly
converting it to a <classname>Glib::ustring</classname>. If the string
contained non-ASCII characters and the current locale is not UTF-8 encoded, the
result is a corrupted <classname>Glib::ustring</classname>. You can work around
this with a manual conversion. For instance, to retrieve the
<classname>std::string</classname> from a <classname>ostringstream</classname>:
<programlisting lang="en">std::ostringstream output;
output.imbue(std::locale("")); // use the user's locale for this stream
output &lt;&lt; percentage &lt;&lt; " % done";
label-&gt;set_text(Glib::locale_to_utf8(output.str()));</programlisting>
</para>
</sect2>

</sect1>

<sect1 id="sec-i18n-pitfalls">
      <title>Embûches</title>

      <para>Voici quelques erreurs courantes que vous découvririez peut-être par vous-même. Mais il se peut que ce paragraphe vous aide à les éviter.</para>

<sect2 id="i18n-string-semantics">
        <title>Mêmes chaînes, sémantiques différentes</title>

        <para>Quelquefois deux chaînes en anglais sont identiques, mais ont des significations différentes selon le contexte ; elles ne mériteraient donc probablement pas d'être traduites de la même façon. Comme les chaînes en anglais sont utilisées comme clés de recherche, cela pose problème.</para>

<para lang="en">
In these cases, you should add extra characters to the strings. For instance,
use <literal>"jumps[noun]"</literal> and <literal>"jumps[verb]"</literal>
instead of just <literal>"jumps"</literal> and strip them again outside the
<function>gettext</function> call. If you add extra characters you should also
add a comment for the translators before the <function>gettext</function> call.
Such comments will be shown in the <filename>.po</filename> files. For
instance:
</para>

<programlisting>// note to translators: don't translate the "[noun]" part - it is
// just here to distinguish the string from another "jumps" string
text = strip(gettext("jumps[noun]"), "[noun]");</programlisting>
      </sect2>

<sect2 id="i18n-composition">
  <title>Composition de chaînes</title>

<para>Les programmeurs C se servent de la fonction <function>sprintf()</function> pour composer et concaténer des chaînes. Le C++ favorise les flux, mais malheureusement, cette approche rend la traduction difficile, parce que chaque fragment de texte est traduit séparément sans permettre aux traducteurs de les ré-agencer selon la grammaire de la langue.</para>

<para>Par exemple, ce code risque d'être sujet à problèmes :</para>

<programlisting>std::cout &lt;&lt; _("Current amount: ") &lt;&lt; amount
          &lt;&lt; _(" Future: ") &lt;&lt; future &lt;&lt; std::endl;

label.set_text(_("Really delete ") + filename + _(" now?"));</programlisting>

<para lang="en">
So you should either avoid this situation or use
<ulink url="http://developer.gnome.org/glibmm/2.50/classGlib_1_1ustring.html"><function>Glib::ustring::compose()</function></ulink>
which supports syntax such as:
<programlisting lang="en">std::cout &lt;&lt; Glib::ustring::compose(
             _("Current amount: %1 Future: %2"), amount, future) &lt;&lt; std::endl;

label.set_text(Glib::ustring::compose(_("Really delete %1 now?"), filename));</programlisting>
</para>
</sect2>

<sect2 id="i18n-display-size">
        <title>Hypothèse concernant la taille d'affichage des chaînes</title>

        <para>Vous ne savez jamais quel sera l'espace pris à l'écran par une chaîne après traduction. Il est tout à fait possible qu'elle soit deux fois plus longue que la chaîne originelle en anglais. Par chance, la plupart des éléments graphiques <application>gtkmm</application> se redimensionnent à la taille voulue lors de l'exécution.</para>
</sect2>

<sect2 id="i18n-unusual-words">
        <title>Mots inhabituels</title>

        <para>Vous devez éviter les abréviations mystérieuses, l'argot ou du jargon de spécialiste. Ces termes sont généralement difficiles à traduire et souvent même à comprendre pour les autochtones. Par exemple, préférez « application » à « app ».</para>
</sect2>

<sect2 id="i18n-non-ascii-characters">
<title>Utilisation de caractères non-ASCII dans les chaînes</title>

<para>Actuellement, <application>gettext</application> ne prend pas en charge les caractères non-ASCII (c'est-à-dire tout caractère de code supérieur à 127) dans le code source. Par exemple, vous ne pouvez pas utiliser le signe de copyright (©).</para>

        <para lang="en">To work around this, you could write a comment in the
          source code just before the string, telling the translators to
          use the special character if it is available in their languages. For english, you could then make an American English
          <filename>en_US.po</filename> translation which used that special character.</para>
      </sect2>
    </sect1>

    <sect1 id="sec-i18n-getting-help-with-translations">
      <title>Obtenir de l'aide avec les traductions</title>

      <para lang="en">If your program is free software, there is a whole <literal>GNOME</literal>
        subproject devoted to helping you make translations, the
        <ulink url="https://wiki.gnome.org/TranslationProject/"><literal>GNOME</literal>
        Translation Project</ulink>.</para>

      <para lang="en">The way it works is that you upload your source code to a git
        repository where translators can access it, then contact the gnome-i18n
        mailing list and ask to have your program added to the
        <ulink url="http://l10n.gnome.org/module/">list of modules to translate</ulink>.</para>

      <para>Assurez-vous que le fichier <filename>POTFILES.in</filename> dans le sous-répertoire <filename>po/</filename> est à jour (la commande <command>intltool‑update -M</command> peut vous aider pour cela) de façon à ce que les traducteurs aient toujours accès à des fichiers <filename>mon_programme.pot</filename> actualisés et gelez tout simplement les chaînes au moins quelques jours avant de téléverser une nouvelle version en l'annonçant sur gnome-i18n. Selon le nombre de chaînes que votre programme comporte et selon sa popularité, les traductions vont alors commencer à apparaître dans les fichiers <filename>nom_de_langue.po</filename>.</para>

      <para>Notez que la plupart des équipes de traducteurs ne sont constituées que de 1 à 3 personnes ; donc, si votre programme comporte beaucoup de chaînes, cela peut prendre beaucoup de temps avant que quelqu'un ait le temps d'y jeter un coup d'œil. De plus, pas mal de traducteurs ne souhaitent pas dilapider leur temps (la traduction est une tâche très consommatrice de temps) donc, il ne prendront en charge votre projet que s'il est vraiment sérieux (dans le sens, travaillé et maintenu) ; si ce n'est pas le cas il peuvent décider de s'occuper sur d'autres projets.</para>
    </sect1>
</chapter>

<chapter id="chapter-customwidgets">
    <title>Éléments graphiques personnalisés</title>

    <para><application>gtkmm</application> facilite la dérivation de nouveaux éléments graphiques par héritage à partir d'une classe d'élément graphique existante, soit par dérivation à partir d'un conteneur et en y ajoutant des éléments graphiques enfants, soit par dérivation d'un élément graphique simple en modifiant son comportement. Mais vous pouvez parfois trouver qu'il n'y a aucun point de départ convenable. Dans ce cas, vous pouvez implémenter un élément graphique de A à Z.</para>

    <sect1 id="sec-custom-containers">
    <title>Conteneurs personnalisés</title>
    <para lang="en">When deriving from <classname>Gtk::Container</classname>, you should override the following virtual methods:
    <itemizedlist>
      <listitem><para lang="en"><methodname>get_request_mode_vfunc()</methodname>: Return what <literal>Gtk::SizeRequestMode</literal> is preferred by the container.</para></listitem>
      <listitem><para lang="en"><methodname>get_preferred_width_vfunc()</methodname>: Calculate the minimum and natural width of the container.</para></listitem>
      <listitem><para lang="en"><methodname>get_preferred_height_vfunc()</methodname>: Calculate the minimum and natural height of the container.</para></listitem>
      <listitem><para lang="en"><methodname>get_preferred_width_for_height_vfunc()</methodname>: Calculate the minimum and natural width of the container, if it would be given the specified height.</para></listitem>
      <listitem><para lang="en"><methodname>get_preferred_height_for_width_vfunc()</methodname>: Calculate the minimum and natural height of the container, if it would be given the specified width.</para></listitem>
      <listitem><para lang="en"><methodname>on_size_allocate()</methodname>: Position the child widgets, given the height and width that the container has actually been given.</para></listitem>
      <listitem><para lang="en"><methodname>forall_vfunc()</methodname>: Call the same callback for each of the children.</para></listitem>
      <listitem><para lang="en"><methodname>on_add()</methodname>: Add a child widget to the container.</para></listitem>
      <listitem><para lang="en"><methodname>on_remove()</methodname>: Remove a child widget from the container.</para></listitem>
      <listitem><para lang="en"><methodname>child_type_vfunc()</methodname>: Return what type of child can be added.</para></listitem>
    </itemizedlist>
    </para>

    <para>Les fonctions membres virtuelles <methodname>get_request_mode_vfunc()</methodname>, <methodname>get_preferred_width_vfunc()</methodname>, <methodname>get_preferred_height_vfunc()</methodname>, <methodname>get_preferred_width_for_height_vfunc()</methodname>, <methodname>get_preferred_height_for_width_vfunc()</methodname> et <methodname>on_size_allocate()</methodname> contrôlent la disposition des éléments graphiques enfants. Par exemple, si votre conteneur possède deux éléments graphiques enfants, l'un au dessus de l'autre, votre fonction membre <methodname>get_preferred_width_vfunc()</methodname> doit renvoyer la plus grande des largeurs des éléments graphiques enfants et <methodname>get_preferred_height_for_width_vfunc()</methodname> la somme des hauteurs. Si vous voulez de l'espace libre autour les éléments graphiques enfants, vous devez également l'additionner à la largeur et à la hauteur. Votre conteneur d'éléments graphiques se sert de ces résultats pour s'assurer que vos éléments graphiques ont assez de place. En examinant chaque parent de l'élément graphique, et les parents de celui-ci, cette logique détermine éventuellement la taille de la fenêtre de plus haut niveau.</para>

    <para>Vous n'avez pas la garantie d'obtenir le <literal>Gtk::SizeRequestMode</literal> demandé. C'est pourquoi les quatre fonctions membres <methodname>get_preferred_xxx_vfunc()</methodname> doivent renvoyer des valeurs raisonnables.</para>

   <para><methodname>on_size_allocate()</methodname>, toutefois, reçoit les vraies hauteur et largeur que le conteneur parent a décidé de donner à l'élément graphique. Cela peut être plus que le minimum ou même plus que la taille naturelle, par exemple, si la fenêtre de haut niveau a été agrandie. Vous pouvez choisir d'ignorer l'espace supplémentaire et laisser la zone inoccupée, ou bien vous pouvez choisir d'agrandir vos éléments graphiques enfants pour remplir cet espace, ou bien encore vous pouvez choisir d'augmenter l'espace libre entre vos éléments graphiques. C'est votre conteneur, à vous de décider. N'oubliez pas d'appeler <methodname>set_allocation()</methodname> à l'intérieur de votre implémentation de <methodname>on_size_allocate()</methodname> pour utiliser effectivement l'espace alloué offert par le conteneur parent.</para>

  <para>À moins que votre conteneur ne soit une fenêtre de haut niveau dérivée de <classname>Gtk::Window</classname>, vous devez également appeler <methodname>Gtk::Widget::set_has_window(false)</methodname> dans le constructeur. Cela signifie que votre conteneur ne crée pas sa propre <classname>Gdk::Window</classname>, mais utilise la fenêtre du parent. (Notez la différence entre <classname>Gtk::Window</classname> et <classname>Gdk::Window</classname>.) Si votre conteneur n'a pas besoin de sa propre <classname>Gdk::Window</classname> et ne dérive pas d'une <classname>Gtk::Window</classname>, vous devez aussi surdéfinir la fonction membre <methodname>on_realize()</methodname> comme cela est décrit dans la section <link linkend="sec-custom-widgets">Éléments graphiques personnalisés</link>. Et, sauf si votre conteneur dessine directement dans la <classname>Gdk::Window</classname> sous-jacente, vous devrez probablement appeler <methodname>set_redraw_on_allocate(false)</methodname> pour améliorer les performances.</para>

  <para>En surdéfinissant <methodname>forall_vfunc()</methodname> vous permettez aux applications d'opérer sur tous les éléments graphiques enfants du conteneur. Par exemple, <methodname>show_all_children()</methodname> utilise cette possibilité pour trouver tous les éléments graphiques enfants et les afficher.</para>

  <para>Même si votre conteneur possède sa propre fonction membre pour définir ses éléments graphiques enfants, vous devez quand même fournir une implémentation des fonctions membres virtuelles <methodname>on_add()</methodname> et <methodname>on_remove()</methodname> de la classe de base de façon à ce que les fonctions membres add() et remove() fassent quelque chose d'approprié si elles sont appelées.</para>

  <para>Votre implémentation de la fonction membre <methodname>child_type_vfunc()</methodname> doit renvoyer le type d'élément graphique pouvant être ajouté à votre conteneur s'il n'est pas encore rempli. Généralement, c'est à <methodname>Gtk::Widget::get_type()</methodname> d'indiquer quelles sont les classes dérivées de <classname>Gtk::Widget</classname> acceptées. Si le conteneur ne peut plus contenir d'autres éléments graphiques, cette fonction membre doit renvoyer la valeur <literal>G_TYPE_NONE</literal>.</para>


<sect2 id="custom-container-example"><title>Exemple</title>

    <para lang="en">This example implements a container with two child widgets, one above
        the other. Of course, in this case it would be far simpler just to use
        a vertical <classname>Gtk::Box</classname>.</para>

<figure id="figure-custom-container">
  <title>Conteneur personnalisé</title>
  <screenshot>
    <graphic format="PNG" fileref="figures/custom_container.png"/>
  </screenshot>
</figure>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/custom/custom_container/?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>examplewindow.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLEWINDOW_H
#define GTKMM_EXAMPLEWINDOW_H

#include &lt;gtkmm.h&gt;
#include "mycontainer.h"

class ExampleWindow : public Gtk::Window
{
public:
  ExampleWindow();
  virtual ~ExampleWindow();

protected:
  //Signal handlers:
  void on_button_quit();

  //Child widgets:
  Gtk::Box m_VBox;
  MyContainer m_MyContainer;
  Gtk::Button m_Button_One;
  Gtk::Label m_Label_Two;
  Gtk::ButtonBox m_ButtonBox;
  Gtk::Button m_Button_Quit;
};

#endif //GTKMM_EXAMPLEWINDOW_H
</programlisting>
<para lang="en">File: <filename>mycontainer.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_CUSTOM_CONTAINER_MYCONTAINER_H
#define GTKMM_CUSTOM_CONTAINER_MYCONTAINER_H

#include &lt;gtkmm/container.h&gt;

class MyContainer : public Gtk::Container
{
public:
  MyContainer();
  virtual ~MyContainer();

  void set_child_widgets(Gtk::Widget&amp; child_one, Gtk::Widget&amp; child_two);

protected:

  //Overrides:
  Gtk::SizeRequestMode get_request_mode_vfunc() const override;
  void get_preferred_width_vfunc(int&amp; minimum_width, int&amp; natural_width) const override;
  void get_preferred_height_for_width_vfunc(int width, int&amp; minimum_height, int&amp; natural_height) const override;
  void get_preferred_height_vfunc(int&amp; minimum_height, int&amp; natural_height) const override;
  void get_preferred_width_for_height_vfunc(int height, int&amp; minimum_width, int&amp; natural_width) const override;
  void on_size_allocate(Gtk::Allocation&amp; allocation) override;

  void forall_vfunc(gboolean include_internals, GtkCallback callback, gpointer callback_data) override;

  void on_add(Gtk::Widget* child) override;
  void on_remove(Gtk::Widget* child) override;
  GType child_type_vfunc() const override;

  Gtk::Widget* m_child_one;
  Gtk::Widget* m_child_two;
};

#endif //GTKMM_CUSTOM_CONTAINER_MYCONTAINER_H
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;gtkmm/application.h&gt;

int main(int argc, char *argv[])
{
  auto app = Gtk::Application::create(argc, argv, "org.gtkmm.example");

  ExampleWindow window;

  //Shows the window and returns when it is closed.
  return app-&gt;run(window);
}
</programlisting>
<para lang="en">File: <filename>examplewindow.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include &lt;iostream&gt;
#include "examplewindow.h"

ExampleWindow::ExampleWindow()
: m_VBox(Gtk::ORIENTATION_VERTICAL),
  m_Button_One("Child One"),
  m_Label_Two("Child 2", Gtk::ALIGN_END, Gtk::ALIGN_CENTER),
  m_Button_Quit("Quit")
{
  set_title("Custom Container example");
  set_border_width(6);
  set_default_size(400, 200);

  add(m_VBox);

  //Add the child widgets to the custom container:
  m_MyContainer.set_child_widgets(m_Button_One, m_Label_Two);

  m_VBox.pack_start(m_MyContainer, Gtk::PACK_EXPAND_WIDGET);
  m_VBox.pack_start(m_ButtonBox, Gtk::PACK_SHRINK);

  m_ButtonBox.pack_start(m_Button_Quit, Gtk::PACK_SHRINK);
  m_ButtonBox.set_border_width(6);
  m_ButtonBox.set_layout(Gtk::BUTTONBOX_END);
  m_Button_Quit.signal_clicked().connect( sigc::mem_fun(*this,
              &amp;ExampleWindow::on_button_quit) );

  show_all_children();
}

ExampleWindow::~ExampleWindow()
{
}

void ExampleWindow::on_button_quit()
{
  hide();
}

</programlisting>
<para lang="en">File: <filename>mycontainer.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include &lt;iostream&gt;
#include &lt;algorithm&gt; // std::max
#include "mycontainer.h"

MyContainer::MyContainer()
: m_child_one(nullptr), m_child_two(nullptr)
{
  set_has_window(false);
  set_redraw_on_allocate(false);
}

MyContainer::~MyContainer()
{
/*
  // These calls to Gtk::Widget::unparent() are necessary if MyContainer is
  // deleted before its children. But if you use a version of gtkmm where bug
  // https://bugzilla.gnome.org/show_bug.cgi?id=605728
  // has not been fixed (gtkmm 3.7.10 or earlier) and the children are deleted
  // before the container, these calls can make the program crash.
  // That's because on_remove() is not called, when the children are deleted.
  if (m_child_one)
    m_child_one-&gt;unparent();

  if (m_child_two)
    m_child_two-&gt;unparent();
*/
}

void MyContainer::set_child_widgets(Gtk::Widget&amp; child_one,
        Gtk::Widget&amp; child_two)
{
  m_child_one = &amp;child_one;
  m_child_two = &amp;child_two;

  m_child_one-&gt;set_parent(*this);
  m_child_two-&gt;set_parent(*this);
}

//This example container is a simplified VBox with at most two children.
Gtk::SizeRequestMode MyContainer::get_request_mode_vfunc() const
{
  return Gtk::SIZE_REQUEST_HEIGHT_FOR_WIDTH;
}

//Discover the total amount of minimum space and natural space needed by
//this container and its children.
void MyContainer::get_preferred_width_vfunc(int&amp; minimum_width, int&amp; natural_width) const
{
  int child_minimum_width[2] = {0, 0};
  int child_natural_width[2] = {0, 0};

  if(m_child_one &amp;&amp; m_child_one-&gt;get_visible())
    m_child_one-&gt;get_preferred_width(child_minimum_width[0], child_natural_width[0]);

  if(m_child_two &amp;&amp; m_child_two-&gt;get_visible())
    m_child_two-&gt;get_preferred_width(child_minimum_width[1], child_natural_width[1]);

  //Request a width equal to the width of the widest visible child.
  minimum_width = std::max(child_minimum_width[0], child_minimum_width[1]);
  natural_width = std::max(child_natural_width[0], child_natural_width[1]);
}

void MyContainer::get_preferred_height_for_width_vfunc(int width,
   int&amp; minimum_height, int&amp; natural_height) const
{
  int child_minimum_height[2] = {0, 0};
  int child_natural_height[2] = {0, 0};
  int nvis_children = 0;

  if(m_child_one &amp;&amp; m_child_one-&gt;get_visible())
  {
    ++nvis_children;
    m_child_one-&gt;get_preferred_height_for_width(width, child_minimum_height[0],
                                                child_natural_height[0]);
  }

  if(m_child_two &amp;&amp; m_child_two-&gt;get_visible())
  {
    ++nvis_children;
    m_child_two-&gt;get_preferred_height_for_width(width, child_minimum_height[1],
                                                child_natural_height[1]);
  }

  //The allocated height will be divided equally among the visible children.
  //Request a height equal to the number of visible children times the height
  //of the highest child.
  minimum_height = nvis_children * std::max(child_minimum_height[0],
                                            child_minimum_height[1]);
  natural_height = nvis_children * std::max(child_natural_height[0],
                                            child_natural_height[1]);
}

void MyContainer::get_preferred_height_vfunc(int&amp; minimum_height, int&amp; natural_height) const
{
  int child_minimum_height[2] = {0, 0};
  int child_natural_height[2] = {0, 0};
  int nvis_children = 0;

  if(m_child_one &amp;&amp; m_child_one-&gt;get_visible())
  {
    ++nvis_children;
    m_child_one-&gt;get_preferred_height(child_minimum_height[0], child_natural_height[0]);
  }

  if(m_child_two &amp;&amp; m_child_two-&gt;get_visible())
  {
    ++nvis_children;
    m_child_two-&gt;get_preferred_height(child_minimum_height[1], child_natural_height[1]);
  }

  //The allocated height will be divided equally among the visible children.
  //Request a height equal to the number of visible children times the height
  //of the highest child.
  minimum_height = nvis_children * std::max(child_minimum_height[0],
                                            child_minimum_height[1]);
  natural_height = nvis_children * std::max(child_natural_height[0],
                                            child_natural_height[1]);
}

void MyContainer::get_preferred_width_for_height_vfunc(int height,
   int&amp; minimum_width, int&amp; natural_width) const
{
  int child_minimum_width[2] = {0, 0};
  int child_natural_width[2] = {0, 0};
  int nvis_children = 0;

  //Get number of visible children.
  if(m_child_one &amp;&amp; m_child_one-&gt;get_visible())
    ++nvis_children;
  if(m_child_two &amp;&amp; m_child_two-&gt;get_visible())
    ++nvis_children;

  if(nvis_children &gt; 0)
  {
    //Divide the height equally among the visible children.
    const int height_per_child = height / nvis_children;

    if(m_child_one &amp;&amp; m_child_one-&gt;get_visible())
      m_child_one-&gt;get_preferred_width_for_height(height_per_child,
                   child_minimum_width[0], child_natural_width[0]);

    if(m_child_two &amp;&amp; m_child_two-&gt;get_visible())
      m_child_two-&gt;get_preferred_width_for_height(height_per_child,
                   child_minimum_width[1], child_natural_width[1]);
  }

  //Request a width equal to the width of the widest child.
  minimum_width = std::max(child_minimum_width[0], child_minimum_width[1]);
  natural_width = std::max(child_natural_width[0], child_natural_width[1]);
}

void MyContainer::on_size_allocate(Gtk::Allocation&amp; allocation)
{
  //Do something with the space that we have actually been given:
  //(We will not be given heights or widths less than we have requested, though
  //we might get more.)

  //Use the offered allocation for this container:
  set_allocation(allocation);

  //Get number of visible children.
  int nvis_children = 0;
  if(m_child_one &amp;&amp; m_child_one-&gt;get_visible())
    ++nvis_children;
  if(m_child_two &amp;&amp; m_child_two-&gt;get_visible())
    ++nvis_children;

  if(nvis_children &lt;= 0)
    return;

  //Assign space to the children:
  Gtk::Allocation child_allocation_one;
  Gtk::Allocation child_allocation_two;

  //Place the first child at the top-left:
  child_allocation_one.set_x( allocation.get_x() );
  child_allocation_one.set_y( allocation.get_y() );

  //Make it take up the full width available:
  child_allocation_one.set_width( allocation.get_width() );

  if(m_child_one &amp;&amp; m_child_one-&gt;get_visible())
  {
    //Divide the height equally among the visible children.
    child_allocation_one.set_height( allocation.get_height() / nvis_children);
    m_child_one-&gt;size_allocate(child_allocation_one);
  }
  else
    child_allocation_one.set_height(0);

  //Place the second child below the first child:
  child_allocation_two.set_x( allocation.get_x() );
  child_allocation_two.set_y( allocation.get_y() +
          child_allocation_one.get_height());

  //Make it take up the full width available:
  child_allocation_two.set_width( allocation.get_width() );

  //Make it take up the remaining height:
  child_allocation_two.set_height( allocation.get_height() -
          child_allocation_one.get_height());

  if(m_child_two &amp;&amp; m_child_two-&gt;get_visible())
    m_child_two-&gt;size_allocate(child_allocation_two);
}

void MyContainer::forall_vfunc(gboolean, GtkCallback callback, gpointer callback_data)
{
  if(m_child_one)
    callback(m_child_one-&gt;gobj(), callback_data);

  if(m_child_two)
    callback(m_child_two-&gt;gobj(), callback_data);
}

void MyContainer::on_add(Gtk::Widget* child)
{
  if(!m_child_one)
  {
    m_child_one = child;
    m_child_one-&gt;set_parent(*this);
  }
  else if(!m_child_two)
  {
    m_child_two = child;
    m_child_two-&gt;set_parent(*this);
  }
}

void MyContainer::on_remove(Gtk::Widget* child)
{
  if(child)
  {
    const bool visible = child-&gt;get_visible();
    bool found = false;

    if(child == m_child_one)
    {
      m_child_one = nullptr;
      found = true;
    }
    else if(child == m_child_two)
    {
      m_child_two = nullptr;
      found = true;
    }

    if(found)
    {
      child-&gt;unparent();

      if(visible)
        queue_resize();
    }
  }
}

GType MyContainer::child_type_vfunc() const
{
  //If there is still space for one widget, then report the type of widget that
  //may be added.
  if(!m_child_one || !m_child_two)
    return Gtk::Widget::get_type();
  else
  {
    //No more widgets may be added.
    return G_TYPE_NONE;
  }
}
</programlisting>
<!-- end inserted example code -->
</sect2>

    </sect1>

    <sect1 id="sec-custom-widgets">
    <title>Éléments graphiques personnalisés</title>
    <para>En dérivant directement de la classe <classname>Gtk::Widget</classname>, vous pouvez faire tous les dessins voulus directement dans votre élément graphique plutôt que seulement placer des éléments graphiques enfants. Par exemple, un objet <classname>Gtk::Label</classname> écrit directement le texte de l'étiquette sans passer par l'intermédiaire d'autres éléments graphiques.</para>

    <para lang="en">When deriving from <classname>Gtk::Widget</classname>, you should
        override the following virtual methods. The methods marked (optional)
        need not be overridden in all custom widgets. The base class's methods
        may be appropriate.
    <itemizedlist>
      <listitem><para lang="en"><methodname>get_request_mode_vfunc()</methodname>: (optional) Return what <literal>Gtk::SizeRequestMode</literal> is preferred by the widget.</para></listitem>
      <listitem><para lang="en"><methodname>get_preferred_width_vfunc()</methodname>: Calculate the minimum and natural width of the widget.</para></listitem>
      <listitem><para lang="en"><methodname>get_preferred_height_vfunc()</methodname>: Calculate the minimum and natural height of the widget.</para></listitem>
      <listitem><para lang="en"><methodname>get_preferred_width_for_height_vfunc()</methodname>: Calculate the minimum and natural width of the widget, if it would be given the specified height.</para></listitem>
      <listitem><para lang="en"><methodname>get_preferred_height_for_width_vfunc()</methodname>: Calculate the minimum and natural height of the widget, if it would be given the specified width.</para></listitem>
      <listitem><para lang="en"><methodname>on_size_allocate()</methodname>: Position the widget, given the height and width that it has actually been given.</para></listitem>
      <listitem><para lang="en"><methodname>on_realize()</methodname>: Associate a <classname>Gdk::Window</classname> with the widget.</para></listitem>
      <listitem><para lang="en"><methodname>on_unrealize()</methodname>: (optional) Break the association with the <classname>Gdk::Window</classname>. </para></listitem>
      <listitem><para lang="en"><methodname>on_map()</methodname>: (optional)</para></listitem>
      <listitem><para lang="en"><methodname>on_unmap()</methodname>: (optional)</para></listitem>
      <listitem><para lang="en"><methodname>on_draw()</methodname>: Draw on the supplied <classname>Cairo::Context</classname>.</para></listitem>
    </itemizedlist>
    </para>

    <para>Les six premières fonctions membres dans le tableau précédent sont également surdéfinies dans les conteneurs personnalisés. Elles sont brièvement décrites dans la section <link linkend="sec-custom-containers">Conteneurs personnalisés</link>.</para>

    <para>La plupart des éléments graphiques personnalisés nécessitent leur propre <classname>Gdk::Window</classname> pour tracer dessus. Alors vous pouvez appeler <methodname>Gtk::Widget::set_has_window(true)</methodname> dans votre constructeur (c'est la valeur par défaut). Si vous n'appelez pas <methodname>set_has_window(false)</methodname>, vous devez surdéfinir <methodname>on_realize()</methodname> et appeler à partir de là <methodname>Gtk::Widget::set_realized()</methodname> et <methodname>Gtk::Widget::set_window()</methodname>.</para>

<sect2 id="custom-style-properties">
<title lang="en">Custom Style Properties</title>

<para lang="en">You can add style properties to your widget class, whether it's derived directly
from <classname>Gtk::Widget</classname> or from another widget class. The values of
the style properties can be read from a CSS (Cascading Style Sheets) file. The users
of your widget, or the users of an application program with your widget, can then
modify the style of your widget without modifying the source code.
Useful classes are <classname>Gtk::StyleProperty</classname> and <classname>Gtk::CssProvider</classname>.
With <methodname>Gtk::Widget::get_style_property()</methodname> you can read the values
of both your own style properties and those of your widget's base class. Note that style
properties are not wrapped in <application>gtkmm</application>. See <application>GTK+</application>'s
documentation for lists of existing style properties.
The following example shows a simple use of a custom style property.
</para>
</sect2>

<sect2 id="custom-widget-example"><title>Exemple</title>

<para>Cet exemple implémente un élément graphique qui trace un triangle de Penrose.</para>

<figure id="figure-custom-widget">
  <title>Élément graphique personnalisé</title>
  <screenshot>
    <graphic format="PNG" fileref="figures/custom_widget.png"/>
  </screenshot>
</figure>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/custom/custom_widget/?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>examplewindow.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLEWINDOW_H
#define GTKMM_EXAMPLEWINDOW_H

#include &lt;gtkmm.h&gt;
#include "mywidget.h"

class ExampleWindow : public Gtk::Window
{
public:
  ExampleWindow();
  virtual ~ExampleWindow();

protected:
  //Signal handlers:
  void on_button_quit();

  //Child widgets:
  Gtk::Box m_VBox;
  MyWidget m_MyWidget;
  Gtk::ButtonBox m_ButtonBox;
  Gtk::Button m_Button_Quit;
};

#endif //GTKMM_EXAMPLEWINDOW_H
</programlisting>
<para lang="en">File: <filename>mywidget.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_CUSTOM_WIDGET_MYWIDGET_H
#define GTKMM_CUSTOM_WIDGET_MYWIDGET_H

#include &lt;gtkmm/widget.h&gt;
#include &lt;gtkmm/cssprovider.h&gt;
#include &lt;gtkmm/styleproperty.h&gt;

class MyWidget : public Gtk::Widget
{
public:
  MyWidget();
  virtual ~MyWidget();

protected:

  //Overrides:
  Gtk::SizeRequestMode get_request_mode_vfunc() const override;
  void get_preferred_width_vfunc(int&amp; minimum_width, int&amp; natural_width) const override;
  void get_preferred_height_for_width_vfunc(int width, int&amp; minimum_height, int&amp; natural_height) const  override;
  void get_preferred_height_vfunc(int&amp; minimum_height, int&amp; natural_height) const override;
  void get_preferred_width_for_height_vfunc(int height, int&amp; minimum_width, int&amp; natural_width) const override;
  void on_size_allocate(Gtk::Allocation&amp; allocation) override;
  void on_map() override;
  void on_unmap() override;
  void on_realize() override;
  void on_unrealize() override;
  bool on_draw(const Cairo::RefPtr&lt;Cairo::Context&gt;&amp; cr) override;

  //Signal handler:
  void on_parsing_error(const Glib::RefPtr&lt;const Gtk::CssSection&gt;&amp; section, const Glib::Error&amp; error);

  Gtk::StyleProperty&lt;int&gt; m_scale_prop;
  Glib::RefPtr&lt;Gdk::Window&gt; m_refGdkWindow;
  Glib::RefPtr&lt;Gtk::CssProvider&gt; m_refCssProvider;

  int m_scale;
};

#endif //GTKMM_CUSTOM_WIDGET_MYWIDGET_H
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;gtkmm/application.h&gt;

int main(int argc, char *argv[])
{
  auto app = Gtk::Application::create(argc, argv, "org.gtkmm.example");

  ExampleWindow window;

  //Shows the window and returns when it is closed.
  return app-&gt;run(window);
}
</programlisting>
<para lang="en">File: <filename>mywidget.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "mywidget.h"
#include &lt;gdkmm/general.h&gt;  // for cairo helper functions
#include &lt;iostream&gt;
//#include &lt;gtk/gtkwidget.h&gt; //For GTK_IS_WIDGET()
#include &lt;cstring&gt;

// The MyWidget class uses API which was added in gtkmm 3.15.3 (Gtk::CssProviderError,
// Gtk::CssProvider::signal_parsing_error() and Gtk::CssSection) and in gtkmm 3.15.2
// (Gtk::StyleProperty).

MyWidget::MyWidget() :
  //The GType name will actually be gtkmm__CustomObject_mywidget
  Glib::ObjectBase("mywidget"),
  Gtk::Widget(),
  //Install a style property so that an aspect of this widget may be themed
  //via a CSS style sheet file:
  m_scale_prop(*this, "example_scale", 500),
  m_scale(1000)
{
  set_has_window(true);

  //This shows the GType name, which must be used in the CSS file.
  std::cout &lt;&lt; "GType name: " &lt;&lt; G_OBJECT_TYPE_NAME(gobj()) &lt;&lt; std::endl;

  //This shows that the GType still derives from GtkWidget:
  //std::cout &lt;&lt; "Gtype is a GtkWidget?:" &lt;&lt; GTK_IS_WIDGET(gobj()) &lt;&lt; std::endl;

  // Set the widget name to use in the CSS file.
  set_name("my-widget");

  // If you make a custom widget in C code, based on gtk+'s GtkWidget, there is
  // an alternative to gtk_widget_set_name(): Set a CSS name for your custom
  // class (instead of the widget instance) with gtk_widget_class_set_css_name()
  // (new in gtk+ 3.19.1). That's not possible for custom widgets defined in gtkmm.
  // gtk_widget_class_set_css_name() must be called in the class init function,
  // which can't be customized, when the widget is based on gtkmm's Gtk::Widget.
  //
  // Another alternative: The custom widget inherits the CSS name "widget" from
  // GtkWidget. That name can be used in the CSS file. This is not a very good
  // alternative. GtkWidget's CSS name is not documented. It can probably be
  // changed or removed in the future.

  m_refCssProvider = Gtk::CssProvider::create();
  auto refStyleContext = get_style_context();
  refStyleContext-&gt;add_provider(m_refCssProvider,
    GTK_STYLE_PROVIDER_PRIORITY_APPLICATION);
  m_refCssProvider-&gt;signal_parsing_error().connect(
    sigc::mem_fun(*this, &amp;MyWidget::on_parsing_error));

  try
  {
    m_refCssProvider-&gt;load_from_path("custom_gtk.css");
  }
  catch(const Gtk::CssProviderError&amp; ex)
  {
    std::cerr &lt;&lt; "CssProviderError, Gtk::CssProvider::load_from_path() failed: "
              &lt;&lt; ex.what() &lt;&lt; std::endl;
  }
  catch(const Glib::Error&amp; ex)
  {
    std::cerr &lt;&lt; "Error, Gtk::CssProvider::load_from_path() failed: "
              &lt;&lt; ex.what() &lt;&lt; std::endl;
  }
}

MyWidget::~MyWidget()
{
}

Gtk::SizeRequestMode MyWidget::get_request_mode_vfunc() const
{
  //Accept the default value supplied by the base class.
  return Gtk::Widget::get_request_mode_vfunc();
}

//Discover the total amount of minimum space and natural space needed by
//this widget.
//Let's make this simple example widget always need minimum 60 by 50 and
//natural 100 by 70.
void MyWidget::get_preferred_width_vfunc(int&amp; minimum_width, int&amp; natural_width) const
{
  minimum_width = 60;
  natural_width = 100;
}

void MyWidget::get_preferred_height_for_width_vfunc(int /* width */,
   int&amp; minimum_height, int&amp; natural_height) const
{
  minimum_height = 50;
  natural_height = 70;
}

void MyWidget::get_preferred_height_vfunc(int&amp; minimum_height, int&amp; natural_height) const
{
  minimum_height = 50;
  natural_height = 70;
}

void MyWidget::get_preferred_width_for_height_vfunc(int /* height */,
   int&amp; minimum_width, int&amp; natural_width) const
{
  minimum_width = 60;
  natural_width = 100;
}

void MyWidget::on_size_allocate(Gtk::Allocation&amp; allocation)
{
  //Do something with the space that we have actually been given:
  //(We will not be given heights or widths less than we have requested, though
  //we might get more)

  //Use the offered allocation for this container:
  set_allocation(allocation);

  if(m_refGdkWindow)
  {
    m_refGdkWindow-&gt;move_resize( allocation.get_x(), allocation.get_y(),
            allocation.get_width(), allocation.get_height() );
  }
}

void MyWidget::on_map()
{
  //Call base class:
  Gtk::Widget::on_map();
}

void MyWidget::on_unmap()
{
  //Call base class:
  Gtk::Widget::on_unmap();
}

void MyWidget::on_realize()
{
  //Do not call base class Gtk::Widget::on_realize().
  //It's intended only for widgets that set_has_window(false).

  set_realized();

  //Get the themed style from the CSS file:
  m_scale = m_scale_prop.get_value();
  std::cout &lt;&lt; "m_scale (example_scale from the theme/css-file) is: "
      &lt;&lt; m_scale &lt;&lt; std::endl;

  if(!m_refGdkWindow)
  {
    //Create the GdkWindow:

    GdkWindowAttr attributes;
    memset(&amp;attributes, 0, sizeof(attributes));

    Gtk::Allocation allocation = get_allocation();

    //Set initial position and size of the Gdk::Window:
    attributes.x = allocation.get_x();
    attributes.y = allocation.get_y();
    attributes.width = allocation.get_width();
    attributes.height = allocation.get_height();

    attributes.event_mask = get_events () | Gdk::EXPOSURE_MASK;
    attributes.window_type = GDK_WINDOW_CHILD;
    attributes.wclass = GDK_INPUT_OUTPUT;

    m_refGdkWindow = Gdk::Window::create(get_parent_window(), &amp;attributes,
            GDK_WA_X | GDK_WA_Y);
    set_window(m_refGdkWindow);

    //make the widget receive expose events
    m_refGdkWindow-&gt;set_user_data(gobj());
  }
}

void MyWidget::on_unrealize()
{
  m_refGdkWindow.reset();

  //Call base class:
  Gtk::Widget::on_unrealize();
}

bool MyWidget::on_draw(const Cairo::RefPtr&lt;Cairo::Context&gt;&amp; cr)
{
  const Gtk::Allocation allocation = get_allocation();
  const double scale_x = (double)allocation.get_width() / m_scale;
  const double scale_y = (double)allocation.get_height() / m_scale;
  auto refStyleContext = get_style_context();

  // paint the background
  refStyleContext-&gt;render_background(cr,
    allocation.get_x(), allocation.get_y(),
    allocation.get_width(), allocation.get_height());

  // draw the foreground
  const auto state = refStyleContext-&gt;get_state();
  Gdk::Cairo::set_source_rgba(cr, refStyleContext-&gt;get_color(state));
  cr-&gt;move_to(155.*scale_x, 165.*scale_y);
  cr-&gt;line_to(155.*scale_x, 838.*scale_y);
  cr-&gt;line_to(265.*scale_x, 900.*scale_y);
  cr-&gt;line_to(849.*scale_x, 564.*scale_y);
  cr-&gt;line_to(849.*scale_x, 438.*scale_y);
  cr-&gt;line_to(265.*scale_x, 100.*scale_y);
  cr-&gt;line_to(155.*scale_x, 165.*scale_y);
  cr-&gt;move_to(265.*scale_x, 100.*scale_y);
  cr-&gt;line_to(265.*scale_x, 652.*scale_y);
  cr-&gt;line_to(526.*scale_x, 502.*scale_y);
  cr-&gt;move_to(369.*scale_x, 411.*scale_y);
  cr-&gt;line_to(633.*scale_x, 564.*scale_y);
  cr-&gt;move_to(369.*scale_x, 286.*scale_y);
  cr-&gt;line_to(369.*scale_x, 592.*scale_y);
  cr-&gt;move_to(369.*scale_x, 286.*scale_y);
  cr-&gt;line_to(849.*scale_x, 564.*scale_y);
  cr-&gt;move_to(633.*scale_x, 564.*scale_y);
  cr-&gt;line_to(155.*scale_x, 838.*scale_y);
  cr-&gt;stroke();

  return true;
}

void MyWidget::on_parsing_error(const Glib::RefPtr&lt;const Gtk::CssSection&gt;&amp; section, const Glib::Error&amp; error)
{
  std::cerr &lt;&lt; "on_parsing_error(): " &lt;&lt; error.what() &lt;&lt; std::endl;
  if (section)
  {
    const auto file = section-&gt;get_file();
    if (file)
    {
      std::cerr &lt;&lt; "  URI = " &lt;&lt; file-&gt;get_uri() &lt;&lt; std::endl;
    }

    std::cerr &lt;&lt; "  start_line = " &lt;&lt; section-&gt;get_start_line()+1
              &lt;&lt; ", end_line = " &lt;&lt; section-&gt;get_end_line()+1 &lt;&lt; std::endl;
    std::cerr &lt;&lt; "  start_position = " &lt;&lt; section-&gt;get_start_position()
              &lt;&lt; ", end_position = " &lt;&lt; section-&gt;get_end_position() &lt;&lt; std::endl;
  }
}
</programlisting>
<para lang="en">File: <filename>examplewindow.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"

ExampleWindow::ExampleWindow()
: m_VBox(Gtk::ORIENTATION_VERTICAL),
  m_Button_Quit("Quit")
{
  set_title("Custom Widget example");
  set_border_width(6);
  set_default_size(400, 200);

  add(m_VBox);
  m_VBox.pack_start(m_MyWidget, Gtk::PACK_EXPAND_WIDGET);
  m_MyWidget.show();

  m_VBox.pack_start(m_ButtonBox, Gtk::PACK_SHRINK);

  m_ButtonBox.pack_start(m_Button_Quit, Gtk::PACK_SHRINK);
  m_ButtonBox.set_border_width(6);
  m_ButtonBox.set_layout(Gtk::BUTTONBOX_END);
  m_Button_Quit.signal_clicked().connect( sigc::mem_fun(*this, &amp;ExampleWindow::on_button_quit) );

  show_all_children();
}

ExampleWindow::~ExampleWindow()
{
}

void ExampleWindow::on_button_quit()
{
  hide();
}
</programlisting>
<para lang="en">File: <filename>custom_gtk.css</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
/* Example of a CSS style sheet with a custom style property.
 *
 * The name of the style property must have its canonical form, i.e. characters
 * other than ASCII letters, digits, and hyphens must be replaced by hyphens.
*/

* {
  /* -&lt;widget class name&gt;-&lt;style property canonical name&gt;: &lt;value&gt;; */
  -gtkmm__CustomObject_mywidget-example-scale: 920;
}

#my-widget {
  background-color: rgb(255,0,0);
  color:            rgb(0,0,255);
}

</programlisting>
<!-- end inserted example code -->
</sect2>

    </sect1>



</chapter>

<chapter id="chapter-multi-threaded-programs">
<title lang="en">Multi-threaded programs</title>

<sect1 id="sec-the-constraints">
<title lang="en">The constraints</title>

<para lang="en">
Care is required when writing programs based on <application>gtkmm</application> using
multiple threads of execution, arising from the fact that
<application>libsigc++</application>, and in particular
<classname>sigc::trackable</classname>, are not thread-safe. That's
because none of the complex interactions that occur behind the scenes
when using <application>libsigc++</application> are protected by a
mutex or other means of synchronization.
<footnote>
<para lang="en">
These interactions arise from the fact that, amongst other things, a
class inheriting from <classname>sigc::trackable</classname> will, via
that inheritance, have a <classname>std::list</classname> object
keeping track of slots created by calls to
<function>sigc::mem_fun()</function> representing any of its
non-static methods (more particularly it keeps a list of callbacks
which will null the connected slots on its destruction). Each
<classname>sigc::slot</classname> object also keeps, via
<classname>sigc::slot_rep</classname>, its own
<classname>sigc::trackable</classname> object to track any
<classname>sigc::connection</classname> objects which it needs to
inform about its demise, and also has a function to deregister itself
from any <classname>sigc::trackable</classname> on disconnection or
destruction. <classname>sigc::signal</classname> objects also keep
lists of slots, which will be updated by a call to their
<methodname>connect()</methodname> method or calls to any
<classname>sigc::connection</classname> object relating to such a
connection.
</para>
</footnote>
</para>

<sect2 id="the-rules">
<title lang="en">The rules</title>

<para lang="en">
This requires a number of rules to be observed when writing
multi-threaded programs using <application>gtkmm</application>. These are set out below, but
one point to note is that extra care is required when deriving classes
from <classname>sigc::trackable</classname>, because the effects are
unintuitive (see particularly points 4 and 5 below).
</para>

<orderedlist>

<listitem>
<para lang="en">
Use <classname>Glib::Dispatcher</classname> to invoke <application>gtkmm</application> functions
from worker threads (this is dealt with in more detail in the next
section).
</para>
</listitem>

<listitem>
<para lang="en">
A <classname>sigc::signal</classname> object should be regarded as
owned by the thread which created it. Only that thread should connect
a <classname>sigc::slot</classname> object to the signal object, and
only that thread should <methodname>emit()</methodname> or call
<methodname>operator()()</methodname> on the signal, or null any
connected <classname>sigc::slot</classname> object. It follows
(amongst other things) that any signal object provided by a <application>gtkmm</application>
widget should only be operated on in the main GUI thread and any
object deriving from <classname>sigc::trackable</classname> having its
non-static methods referenced by slots connected to the signal object
should only be destroyed in that thread.
</para>
</listitem>

<listitem>
<para lang="en">
Any <classname>sigc::connection</classname> object should be regarded
as owned by the thread in which the method returning the
<classname>sigc::connection</classname> object was called. Only that
thread should call <classname>sigc::connection</classname> methods on
the object.
</para>
</listitem>

<listitem>
<para lang="en">
A <classname>sigc::slot</classname> object created by a call to
<function>sigc::mem_fun()</function> which references a method of a
class deriving from <classname>sigc::trackable</classname> should
never be copied to another thread, nor destroyed by a different thread
than the one which created it.
</para>
</listitem>

<listitem>
<para lang="en">
If a particular class object derives from
<classname>sigc::trackable</classname>, only one thread should create
<classname>sigc::slot</classname> objects representing any of the
class's non-static methods by calling
<function>sigc::mem_fun()</function>. The first thread to create such
a slot should be regarded as owning the relevant object for the
purpose of creating further slots referencing <emphasis>any</emphasis>
of its non-static methods using that function, or nulling those slots
by disconnecting them or destroying the trackable object.
</para>
</listitem>

<listitem>
<para lang="en">
Although <application>glib</application> is itself thread-safe, any
<application>glibmm</application> wrappers which use
<application>libsigc++</application> will not be. So for example, only
the thread in which a main loop runs should call
<methodname>Glib::SignalIdle::connect()</methodname>,
<methodname>Glib::SignalIO::connect()</methodname>,
<methodname>Glib::SignalTimeout::connect()</methodname>,
<methodname>Glib::SignalTimeout::connect_seconds</methodname>
for that main loop, or manipulate any
<classname>sigc::connection</classname> object returned by them.
</para>
<para lang="en">
The connect*_once() variants,
<methodname>Glib::SignalIdle::connect_once()</methodname>,
<methodname>Glib::SignalTimeout::connect_once()</methodname>,
<methodname>Glib::SignalTimeout::connect_seconds_once()</methodname>,
are thread-safe for any case where the slot is not created by a call to
<function>sigc::mem_fun()</function> which represents a method of a class
deriving from <classname>sigc::trackable</classname>.
</para>
</listitem>

</orderedlist>

</sect2>

</sect1>

<sect1 id="sec-using-glib-dispatcher">
<title lang="en">Using Glib::Dispatcher</title>

<para lang="en">
The slots connected to <classname>sigc::signal</classname> objects
execute in the thread which calls <methodname>emit()</methodname> or
<methodname>operator()()</methodname> on the signal.
<classname>Glib::Dispatcher</classname> does not behave this way:
instead its connected slots execute in the thread in which the
<classname>Glib::Dispatcher</classname> object was constructed (which
must have a glib main loop). If a
<classname>Glib::Dispatcher</classname> object is constructed in the
main GUI thread (which will therefore be the receiver thread), any
worker thread can emit on it and have the connected slots safely
execute <application>gtkmm</application> functions.
</para>

<para lang="en">
Some thread safety rules on the use of
<classname>Glib::Dispatcher</classname> still apply. As mentioned, a
<classname>Glib::Dispatcher</classname> object must be constructed in
the receiver thread (the thread in whose main loop it will execute its
connected slots). By default this is the main program thread, although
there is a <classname>Glib::Dispatcher</classname> constructor which
can take the <classname>Glib::MainContext</classname> object of any
thread which has a main loop. Only the receiver thread should call
<methodname>connect()</methodname> on the
<classname>Glib::Dispatcher</classname> object, or manipulate any
related <classname>sigc::connection</classname> object, unless
additional synchronization is employed. However, any worker thread can
safely emit on the <classname>Glib::Dispatcher</classname> object
without any locking once the receiver thread has connected the slots,
provided that it is constructed before the worker thread is started
(if it is constructed after the thread has started, additional
synchronization will normally be required to ensure visibility).
</para>

<para lang="en">
Aside from the fact that connected slots always execute in the
receiver thread, <classname>Glib::Dispatcher</classname> objects are
similar to <classname>sigc::signal&lt;void&gt;</classname> objects.
They therefore cannot pass unbound arguments nor return a value. The
best way to pass unbound arguments is with a thread-safe
(asynchronous) queue. At the time of writing
<application>glibmm</application> does not have one, although most
people writing multi-threaded code will have one available to them
(they are relatively easy to write although there are subtleties in
combining thread safety with strong exception safety).
</para>

<para lang="en">
A <classname>Glib::Dispatcher</classname> object can be emitted on by
the receiver thread as well as by a worker thread, although this
should be done within reasonable bounds. On unix-like systems
<classname>Glib::Dispatcher</classname> objects share a single common
pipe, which could in theory at least fill up on a very heavily loaded
system running a program with a very large number of
<classname>Dispatcher</classname> objects in use. Were the pipe to
fill up before the receiver thread's main loop has had an opportunity
to read from it to empty it, and the receiver thread attempt to emit
and so write to it when it is in that condition, the receiver thread
would block on the write, so deadlocking. Where the receiver thread is
to emit, a normal <classname>sigc::signal&lt;void&gt;</classname>
object could of course be used instead.
</para>

</sect1>

<sect1 id="sec-multithread-example">
<title>Exemple</title>
<para lang="en">
This is an example program with two threads, one GUI thread, like in all
<application>gtkmm</application> programs, and one worker thread. The worker thread is created when you
press the <literal>Start work</literal> button. It is deleted when the work is
finished, when you press the <literal>Stop work</literal> button, or when you
press the <literal>Quit</literal> button.
</para>

<para lang="en">
A <classname>Glib::Dispatcher</classname> is used for sending notifications
from the worker thread to the GUI thread. The <classname>ExampleWorker</classname>
class contains data which is accessed by both threads. This data is protected
by a <classname>std::mutex</classname>.
Only the GUI thread updates the GUI.
</para>

<figure id="figure-multithread">
  <title lang="en">Multi-Threaded Program</title>
  <screenshot>
    <graphic format="PNG" fileref="figures/multithread.png"/>
  </screenshot>
</figure>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/multithread?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>exampleworker.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLEWORKER_H
#define GTKMM_EXAMPLEWORKER_H

#include &lt;gtkmm.h&gt;
#include &lt;thread&gt;
#include &lt;mutex&gt;

class ExampleWindow;

class ExampleWorker
{
public:
  ExampleWorker();

  // Thread function.
  void do_work(ExampleWindow* caller);

  void get_data(double* fraction_done, Glib::ustring* message) const;
  void stop_work();
  bool has_stopped() const;

private:
  // Synchronizes access to member data.
  mutable std::mutex m_Mutex;

  // Data used by both GUI thread and worker thread.
  bool m_shall_stop;
  bool m_has_stopped;
  double m_fraction_done;
  Glib::ustring m_message;
};

#endif // GTKMM_EXAMPLEWORKER_H
</programlisting>
<para lang="en">File: <filename>examplewindow.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLEWINDOW_H
#define GTKMM_EXAMPLEWINDOW_H

#include &lt;gtkmm.h&gt;
#include "exampleworker.h"

class ExampleWindow : public Gtk::Window
{
public:
  ExampleWindow();

  // Called from the worker thread.
  void notify();

private:
  // Signal handlers.
  void on_start_button_clicked();
  void on_stop_button_clicked();
  void on_quit_button_clicked();

  void update_start_stop_buttons();
  void update_widgets();

  // Dispatcher handler.
  void on_notification_from_worker_thread();

  // Member data.
  Gtk::Box m_VBox;
  Gtk::ButtonBox m_ButtonBox;
  Gtk::Button m_ButtonStart;
  Gtk::Button m_ButtonStop;
  Gtk::Button m_ButtonQuit;
  Gtk::ProgressBar m_ProgressBar;
  Gtk::ScrolledWindow m_ScrolledWindow;
  Gtk::TextView m_TextView;

  Glib::Dispatcher m_Dispatcher;
  ExampleWorker m_Worker;
  std::thread* m_WorkerThread;
};

#endif // GTKMM_EXAMPLEWINDOW_H
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;gtkmm/application.h&gt;

int main (int argc, char* argv[])
{
  auto app = Gtk::Application::create(argc, argv, "org.gtkmm.example");

  ExampleWindow window;

  //Shows the window and returns when it is closed.
  return app-&gt;run(window);
}
</programlisting>
<para lang="en">File: <filename>exampleworker.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "exampleworker.h"
#include "examplewindow.h"
#include &lt;sstream&gt;
#include &lt;chrono&gt;

ExampleWorker::ExampleWorker() :
  m_Mutex(),
  m_shall_stop(false),
  m_has_stopped(false),
  m_fraction_done(0.0),
  m_message()
{
}

// Accesses to these data are synchronized by a mutex.
// Some microseconds can be saved by getting all data at once, instead of having
// separate get_fraction_done() and get_message() methods.
void ExampleWorker::get_data(double* fraction_done, Glib::ustring* message) const
{
  std::lock_guard&lt;std::mutex&gt; lock(m_Mutex);

  if (fraction_done)
    *fraction_done = m_fraction_done;

  if (message)
    *message = m_message;
}

void ExampleWorker::stop_work()
{
  std::lock_guard&lt;std::mutex&gt; lock(m_Mutex);
  m_shall_stop = true;
}

bool ExampleWorker::has_stopped() const
{
  std::lock_guard&lt;std::mutex&gt; lock(m_Mutex);
  return m_has_stopped;
}

void ExampleWorker::do_work(ExampleWindow* caller)
{
  {
    std::lock_guard&lt;std::mutex&gt; lock(m_Mutex);
    m_has_stopped = false;
    m_fraction_done = 0.0;
    m_message = "";
  } // The mutex is unlocked here by lock's destructor.

  // Simulate a long calculation.
  for (int i = 0; ; ++i) // do until break
  {
    std::this_thread::sleep_for(std::chrono::milliseconds(250));

    {
      std::lock_guard&lt;std::mutex&gt; lock(m_Mutex);

      m_fraction_done += 0.01;

      if (i % 4 == 3)
      {
        std::ostringstream ostr;
        ostr &lt;&lt; (m_fraction_done * 100.0) &lt;&lt; "% done\n";
        m_message += ostr.str();
      }

      if (m_fraction_done &gt;= 1.0)
      {
        m_message += "Finished";
        break;
      }
      if (m_shall_stop)
      {
        m_message += "Stopped";
        break;
      }
    }

    caller-&gt;notify();
  }

  {
    std::lock_guard&lt;std::mutex&gt; lock(m_Mutex);
    m_shall_stop = false;
    m_has_stopped = true;
  }

  caller-&gt;notify();
}
</programlisting>
<para lang="en">File: <filename>examplewindow.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "examplewindow.h"
#include &lt;iostream&gt;

ExampleWindow::ExampleWindow() :
  m_VBox(Gtk::ORIENTATION_VERTICAL, 5),
  m_ButtonBox(Gtk::ORIENTATION_HORIZONTAL),
  m_ButtonStart("Start work"),
  m_ButtonStop("Stop work"),
  m_ButtonQuit("_Quit", /* mnemonic= */ true),
  m_ProgressBar(),
  m_ScrolledWindow(),
  m_TextView(),
  m_Dispatcher(),
  m_Worker(),
  m_WorkerThread(nullptr)
{
  set_title("Multi-threaded example");
  set_border_width(5);
  set_default_size(300, 300);

  add(m_VBox);

  // Add the ProgressBar.
  m_VBox.pack_start(m_ProgressBar, Gtk::PACK_SHRINK);

  m_ProgressBar.set_text("Fraction done");
  m_ProgressBar.set_show_text();

  // Add the TextView, inside a ScrolledWindow.
  m_ScrolledWindow.add(m_TextView);

  // Only show the scrollbars when they are necessary.
  m_ScrolledWindow.set_policy(Gtk::POLICY_AUTOMATIC, Gtk::POLICY_AUTOMATIC);

  m_VBox.pack_start(m_ScrolledWindow);

  m_TextView.set_editable(false);

  // Add the buttons to the ButtonBox.
  m_VBox.pack_start(m_ButtonBox, Gtk::PACK_SHRINK);

  m_ButtonBox.pack_start(m_ButtonStart, Gtk::PACK_SHRINK);
  m_ButtonBox.pack_start(m_ButtonStop, Gtk::PACK_SHRINK);
  m_ButtonBox.pack_start(m_ButtonQuit, Gtk::PACK_SHRINK);
  m_ButtonBox.set_border_width(5);
  m_ButtonBox.set_spacing(5);
  m_ButtonBox.set_layout(Gtk::BUTTONBOX_END);

  // Connect the signal handlers to the buttons.
  m_ButtonStart.signal_clicked().connect(sigc::mem_fun(*this, &amp;ExampleWindow::on_start_button_clicked));
  m_ButtonStop.signal_clicked().connect(sigc::mem_fun(*this, &amp;ExampleWindow::on_stop_button_clicked));
  m_ButtonQuit.signal_clicked().connect(sigc::mem_fun(*this, &amp;ExampleWindow::on_quit_button_clicked));

  // Connect the handler to the dispatcher.
  m_Dispatcher.connect(sigc::mem_fun(*this, &amp;ExampleWindow::on_notification_from_worker_thread));

  // Create a text buffer mark for use in update_widgets().
  auto buffer = m_TextView.get_buffer();
  buffer-&gt;create_mark("last_line", buffer-&gt;end(), /* left_gravity= */ true);

  update_start_stop_buttons();

  show_all_children();
}

void ExampleWindow::on_start_button_clicked()
{
  if (m_WorkerThread)
  {
    std::cout &lt;&lt; "Can't start a worker thread while another one is running." &lt;&lt; std::endl;
  }
  else
  {
    // Start a new worker thread.
    m_WorkerThread = new std::thread(
      [this]
      {
        m_Worker.do_work(this);
      });
  }
  update_start_stop_buttons();
}

void ExampleWindow::on_stop_button_clicked()
{
  if (!m_WorkerThread)
  {
    std::cout &lt;&lt; "Can't stop a worker thread. None is running." &lt;&lt; std::endl;
  }
  else
  {
   // Order the worker thread to stop.
    m_Worker.stop_work();
    m_ButtonStop.set_sensitive(false);
  }
}

void ExampleWindow::update_start_stop_buttons()
{
  const bool thread_is_running = m_WorkerThread != nullptr;

  m_ButtonStart.set_sensitive(!thread_is_running);
  m_ButtonStop.set_sensitive(thread_is_running);
}

void ExampleWindow::update_widgets()
{
  double fraction_done;
  Glib::ustring message_from_worker_thread;
  m_Worker.get_data(&amp;fraction_done, &amp;message_from_worker_thread);

  m_ProgressBar.set_fraction(fraction_done);

  if (message_from_worker_thread != m_TextView.get_buffer()-&gt;get_text())
  {
    auto buffer = m_TextView.get_buffer();
    buffer-&gt;set_text(message_from_worker_thread);

    // Scroll the last inserted line into view. That's somewhat complicated.
    Gtk::TextIter iter = buffer-&gt;end();
    iter.set_line_offset(0); // Beginning of last line
    auto mark = buffer-&gt;get_mark("last_line");
    buffer-&gt;move_mark(mark, iter);
    m_TextView.scroll_to(mark);
    // TextView::scroll_to(iter) is not perfect.
    // We do need a TextMark to always get the last line into view.
  }
}

void ExampleWindow::on_quit_button_clicked()
{
  if (m_WorkerThread)
  {
    // Order the worker thread to stop and wait for it to stop.
    m_Worker.stop_work();
    if (m_WorkerThread-&gt;joinable())
      m_WorkerThread-&gt;join();
  }
  hide();
}

// notify() is called from ExampleWorker::do_work(). It is executed in the worker
// thread. It triggers a call to on_notification_from_worker_thread(), which is
// executed in the GUI thread.
void ExampleWindow::notify()
{
  m_Dispatcher.emit();
}

void ExampleWindow::on_notification_from_worker_thread()
{
  if (m_WorkerThread &amp;&amp; m_Worker.has_stopped())
  {
    // Work is done.
    if (m_WorkerThread-&gt;joinable())
      m_WorkerThread-&gt;join();
    delete m_WorkerThread;
    m_WorkerThread = nullptr;
    update_start_stop_buttons();
  }
  update_widgets();
}
</programlisting>
<!-- end inserted example code -->

</sect1>

</chapter>

<chapter id="chapter-recommended-techniques">
<title>Techniques recommandées</title>

<para>Ce chapitre est simplement un condensé de pratiques de bon sens, de lignes directrices générales, et de conseils pour créer des applications <application>gtkmm</application>.</para>

<para lang="en">Use GNU <application>autoconf</application> and
    <application>automake</application>! They are your friends :)
    <application>Automake</application> examines C files, determines how they
    depend on each other, and generates a <filename>Makefile</filename> so the
    files can be compiled in the correct order.
    <application>Autoconf</application> permits automatic configuration of
    software installation, handling a large number of system quirks to increase
    portability.
</para>

<para>Sous-classez vos éléments graphiques pour mieux organiser votre code. Vous devrez probablement sous-classer au moins votre fenêtre principale <classname>Window</classname>. Ensuite, vous pouvez faire des éléments graphiques enfants et des fonctions membres gestionnaires des signaux de cette classe.</para>

<para>Créez vos propres signaux au lieu de transmettre des pointeurs. Les objets peuvent communiquer entre eux par l'intermédiaire de signaux et de gestionnaires de signaux. C'est plus simple que des objets enregistrant des pointeurs vers d'autres objets, et vice versa, en appelant mutuellement leurs fonctions membres. Les classes de <application>gtkmm</application> utilisent une version spéciale de <classname>sigc::signal</classname>, mais vous pouvez utiliser les signaux normaux tels que décrits dans la documentation de <application>libsigc++</application>.</para>

<sect1 id="sec-application-lifetime">
    <title>Durée de vie d'une application</title>
<para lang="en">Most applications will have only one <classname>Window</classname>, or
    only one main window. These applications can use the
    <methodname>Gtk::Application::run(Gtk::Window&amp;)</methodname> overload. It shows
    the window and returns when the window has been hidden. This might happen
    when the user closes the window, or when your code decides to
    <methodname>hide()</methodname> the window. You can prevent the user from
    closing the window (for instance, if there are unsaved changes) by
    overriding <methodname>Gtk::Window::on_delete_event()</methodname>.</para>
<para>La plupart de nos exemples utilisent cette technique.</para>
</sect1>

<sect1 id="sec-using-a-gtkmm-widget">
<title>Utilisation d'un élément graphique <application>gtkmm</application></title>

<para>Nos exemples adoptent tous la même structure. Ils suivent ces étapes pour l'utilisation d'un <classname>Élément graphique</classname> :</para>

<para>

<orderedlist>
<listitem>
<para>Déclarer une variable du type de l'<classname>Élément graphique</classname> que vous souhaitez utiliser, généralement en tant que variable membre d'une classe conteneur dérivée. Vous pouvez également déclarer un pointeur sur le type de l'élément graphique et le créer avec <literal>new</literal> dans votre code. Même si vous utilisez l'élément graphique par l'intermédiaire d'un pointeur, ce sera probablement mieux de faire en sorte que ce pointeur soit une variable membre d'une classe conteneur ; vous pouvez ainsi y accéder ultérieurement.</para>
</listitem>

<listitem>
<para>Définissez les attributs de l'élément graphique. Si l'élément graphique n'a pas de constructeur par défaut, vous devez l'initialiser à l'aide de la liste d'initialisations du constructeur de la classe conteneur.</para>
</listitem>

<listitem>
<para>Connectez tout signal que vous souhaitez utiliser aux gestionnaires appropriés.</para>
</listitem>

<listitem>
<para>Empaquetez l'élément graphique dans un conteneur par un appel approprié, par exemple <methodname>Gtk::Container::add()</methodname> ou <methodname>pack_start()</methodname>.</para>
</listitem>

<listitem>
<para>Appelez <methodname>show()</methodname> pour afficher l'élément graphique.</para>
</listitem>

</orderedlist>

</para>

<para><methodname>Gtk::Widget::show()</methodname> fait savoir à <application>gtkmm</application> que vous avez terminé de définir les attributs de l'élément graphique et qu'il est prêt à être affiché. Vous pouvez utiliser <methodname>Gtk::Widget::hide()</methodname> pour le faire disparaître à nouveau. L'ordre dans lequel vous affichez les éléments graphiques n'a pas d'importance, mais nous suggérons de n'afficher qu'en dernier la fenêtre de plus haut niveau ; ainsi, la fenêtre globale apparaît en ayant tout son contenu déjà dessinée. Sinon, l'utilisateur voit d'abord une fenêtre vierge dans laquelle les éléments graphiques sont tracés progressivement.</para>

</sect1>
</chapter>

<chapter id="chapter-building-applications">
<title lang="en">Building applications</title>

<para lang="en">
This chapter is similar to the "Building applications" chapter in the
<ulink url="https://developer.gnome.org/gtk3/stable/">GTK+ 3 Reference Manual</ulink>.
The same application is built, but <application>gtkmm</application> is used instead of <application>GTK+</application>.
</para>
<para lang="en">
An application consists of a number of files:
<variablelist>
  <varlistentry>
    <term lang="en">The binary file</term>
    <listitem><para lang="en">This gets installed in <filename>/usr/bin</filename>.</para></listitem>
  </varlistentry>
  <varlistentry>
    <term lang="en">A desktop file</term>
    <listitem><para lang="en">The desktop file provides important information about the application
      to the desktop shell, such as its name, icon, D-Bus name, commandline to launch it,
      etc. It is installed in <filename>/usr/share/applications</filename>.</para></listitem>
  </varlistentry>
  <varlistentry>
    <term lang="en">An icon</term>
    <listitem><para lang="en">The icon gets installed in <filename>/usr/share/icons/hicolor/48x48/apps</filename>,
      where it will be found regardless of the current theme.</para></listitem>
  </varlistentry>
  <varlistentry>
    <term lang="en">A settings schema</term>
    <listitem><para lang="en">If the application uses <classname>Gio::Settings</classname>,
      it will install its schema in <filename>/usr/share/glib-2.0/schemas</filename>,
      so that tools like dconf-editor can find it.</para></listitem>
  </varlistentry>
  <varlistentry>
    <term lang="en">Other resources</term>
    <listitem><para lang="en">Other files, such as <classname>Gtk::Builder</classname> ui files,
      are best loaded from resources stored in the application binary itself. This
      eliminates the need for most of the files that would traditionally be installed
      in an application-specific location in <filename>/usr/share</filename>.</para></listitem>
  </varlistentry>
</variablelist>
</para>

<para lang="en">
<application>gtkmm</application> includes application support that is built on top of <classname>Gio::Application</classname>.
In this chapter we'll build a simple application by starting from scratch, adding more
and more pieces over time. Along the way, we'll learn about <classname>Gtk::Application</classname>,
<classname>Gtk::Builder</classname>, resources, application menus, settings,
<classname>Gtk::HeaderBar</classname>, <classname>Gtk::Stack</classname>,
<classname>Gtk::SearchBar</classname>, <classname>Gtk::ListBox</classname>, and more.
</para>

<para lang="en">
The full, buildable sources for these examples can be found in the
<filename>examples/book/buildapp</filename> directory of the
<application>gtkmm-documentation</application> source distribution, or online in the
<ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/buildapp"><application>gtkmm-documentation</application>
git repository</ulink>. You can build each example separately by using make with the
<filename>Makefile.example</filename> file. For more information, see the
<filename>README</filename> included in the <filename>buildapp</filename> directory.
</para>

<sect1 id="sec-buildapp-trivial-app">
<title lang="en">A trivial application</title>

<para lang="en">
When using <classname>Gtk::Application</classname>, the <function>main()</function> function
can be very simple. We just call <methodname>Gio::Application::run()</methodname> on an
instance of our application class.
</para>

<para lang="en">
All the application logic is in the application class, which is a subclass of
<classname>Gtk::Application</classname>. Our example does not yet have any interesting
functionality. All it does is open a window when it is activated without arguments,
and open the files it is given, if it is started with arguments. (Or rather, our
application class tries to open the files, but our subclassed application window
does not yet do what it's told to do.)
</para>

<para lang="en">
To handle these two cases, we override <methodname>signal_activate()</methodname>'s
default handler, which gets called when the application is launched without commandline
arguments, and <methodname>signal_open()</methodname>'s default handler, which gets
called when the application is launched with commandline arguments.
</para>

<para lang="en"><ulink url="http://developer.gnome.org/glibmm/2.50/classGio_1_1Application.html">Gio::Application Reference</ulink></para>

<para lang="en">
Another important class that is part of the application support in <application>gtkmm</application> is
<classname>Gtk::ApplicationWindow</classname>. It is typically subclassed as well.
Our subclass does not do anything yet, so we will just get an empty window.
</para>

<para lang="en">
As part of the initial setup of our application, we also create an icon and a desktop file.
Note that @bindir@ in the desktop file needs to be replaced with the actual path
to the binary before this desktop file can be used.
</para>

<para lang="en">
Here is what we've achieved so far:
</para>

<figure id="figure-buildapp-trivial-app">
  <title lang="en">A trivial application</title>
  <screenshot>
    <graphic format="PNG" fileref="figures/buildapp_trivial_app.png"/>
  </screenshot>
</figure>

<para lang="en">
This does not look very impressive yet, but our application is already presenting itself
on the session bus, it has single-instance semantics, and it accepts files as commandline arguments.
</para>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/buildapp/step1?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>exampleappwindow.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLEAPPWINDOW_H_
#define GTKMM_EXAMPLEAPPWINDOW_H_

#include &lt;gtkmm.h&gt;

class ExampleAppWindow : public Gtk::ApplicationWindow
{
public:
  ExampleAppWindow();

  void open_file_view(const Glib::RefPtr&lt;Gio::File&gt;&amp; file);
};

#endif /* GTKMM_EXAMPLEAPPWINDOW_H */
</programlisting>
<para lang="en">File: <filename>exampleapplication.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLEAPPLICATION_H
#define GTKMM_EXAMPLEAPPLICATION_H

#include &lt;gtkmm.h&gt;

class ExampleAppWindow;

class ExampleApplication: public Gtk::Application
{
protected:
  ExampleApplication();

public:
  static Glib::RefPtr&lt;ExampleApplication&gt; create();

protected:
  // Override default signal handlers:
  void on_activate() override;
  void on_open(const Gio::Application::type_vec_files&amp; files,
    const Glib::ustring&amp; hint) override;

private:
  ExampleAppWindow* create_appwindow();
  void on_hide_window(Gtk::Window* window);
};

#endif /* GTKMM_EXAMPLEAPPLICATION_H */
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "exampleapplication.h"

int main(int argc, char* argv[])
{
  auto application = ExampleApplication::create();

  // Start the application, showing the initial window,
  // and opening extra views for any files that it is asked to open,
  // for instance as a command-line parameter.
  // run() will return when the last window has been closed.
  return application-&gt;run(argc, argv);
}
</programlisting>
<para lang="en">File: <filename>exampleapplication.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "exampleapplication.h"
#include "exampleappwindow.h"

ExampleApplication::ExampleApplication()
: Gtk::Application("org.gtkmm.examples.application", Gio::APPLICATION_HANDLES_OPEN)
{
}

Glib::RefPtr&lt;ExampleApplication&gt; ExampleApplication::create()
{
  return Glib::RefPtr&lt;ExampleApplication&gt;(new ExampleApplication());
}

ExampleAppWindow* ExampleApplication::create_appwindow()
{
  auto appwindow = new ExampleAppWindow();

  // Make sure that the application runs for as long this window is still open.
  add_window(*appwindow);

  // Gtk::Application::add_window() connects a signal handler to the window's
  // signal_hide(). That handler removes the window from the application.
  // If it's the last window to be removed, the application stops running.
  // Gtk::Window::set_application() does not connect a signal handler, but is
  // otherwise equivalent to Gtk::Application::add_window().

  // Delete the window when it is hidden.
  appwindow-&gt;signal_hide().connect(sigc::bind&lt;Gtk::Window*&gt;(sigc::mem_fun(*this,
    &amp;ExampleApplication::on_hide_window), appwindow));

  return appwindow;
}

void ExampleApplication::on_activate()
{
  // The application has been started, so let's show a window.
  auto appwindow = create_appwindow();
  appwindow-&gt;present();
}

void ExampleApplication::on_open(const Gio::Application::type_vec_files&amp; files,
  const Glib::ustring&amp; /* hint */)
{
  // The application has been asked to open some files,
  // so let's open a new view for each one.
  ExampleAppWindow* appwindow = nullptr;
  auto windows = get_windows();
  if (windows.size() &gt; 0)
    appwindow = dynamic_cast&lt;ExampleAppWindow*&gt;(windows[0]);

  if (!appwindow)
    appwindow = create_appwindow();

  for (const auto&amp; file : files)
    appwindow-&gt;open_file_view(file);

  appwindow-&gt;present();
}

void ExampleApplication::on_hide_window(Gtk::Window* window)
{
  delete window;
}
</programlisting>
<para lang="en">File: <filename>exampleappwindow.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "exampleappwindow.h"

ExampleAppWindow::ExampleAppWindow()
: Gtk::ApplicationWindow()
{
}

void ExampleAppWindow::open_file_view(const Glib::RefPtr&lt;Gio::File&gt;&amp; /* file */)
{
}

</programlisting>
<para lang="en">File: <filename>exampleapp.desktop</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
[Desktop Entry]
Type=Application
Name=Gtkmm example
GenericName=Example
Comment=From the "Programming with gtkmm 3" tutorial
Icon=exampleapp
StartupNotify=true
Exec=@bindir@/exampleapp %U
Categories=GNOME;GTK;Utility
</programlisting>
<!-- end inserted example code -->

</sect1>

<sect1 id="sec-buildapp-populating-window">
<title lang="en">Populating the window</title>

<para lang="en">
In this step, we use a <classname>Gtk::Builder</classname> instance to associate a
<classname>Gtk::Builder</classname> ui file with our application window class.
</para>

<para lang="en">
Our simple ui file puts a <classname>Gtk::HeaderBar</classname> on top of a
<classname>Gtk::Stack</classname> widget. The header bar contains a
<classname>Gtk::StackSwitcher</classname>, which is a standalone widget to show a row
of 'tabs' for the pages of a <classname>Gtk::Stack</classname>. 
</para>

<para lang="en">
To make use of this file in our application, we revisit our
<classname>Gtk::ApplicationWindow</classname> subclass, and call
<methodname>Gtk::Builder::create_from_resource()</methodname> and
<methodname>Gtk::Builder::get_widget_derived()</methodname> from the
<methodname>ExampleAppWindow::create()</methodname> method to get an instance of
our subclassed <classname>Gtk::ApplicationWindow</classname>. See the 
<link linkend="sec-builder-using-derived-widgets">Using derived widgets</link> section
for more information about <methodname>get_widget_derived()</methodname>.
</para>

<para lang="en">
You may have noticed that we use the <methodname>_from_resource()</methodname> variant
of the method that reads the ui file. Now we need to use <application>GLib</application>'s
resource functionality to include the ui file in the binary. This is commonly done by
listing all resources in a .gresource.xml file.
This file has to be converted into a C source file that will be compiled and linked
into the application together with the other source files. To do so, we use the
<application>glib-compile-resources</application> utility:
<screen lang="en">$ glib-compile-resources --target=resources.c --generate-source exampleapp.gresource.xml</screen>
The <link linkend="sec-gio-resource">Gio::Resource and glib-compile-resources</link>
section contains more information about resource files.
</para>

<para lang="en">
Our application now looks like this:
</para>

<figure id="figure-buildapp-populating-window">
  <title lang="en">Populating the window</title>
  <screenshot>
    <graphic format="PNG" fileref="figures/buildapp_populating_window.png"/>
  </screenshot>
</figure>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/buildapp/step2?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>exampleappwindow.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLEAPPWINDOW_H_
#define GTKMM_EXAMPLEAPPWINDOW_H_

#include &lt;gtkmm.h&gt;

class ExampleAppWindow : public Gtk::ApplicationWindow
{
public:
  ExampleAppWindow(BaseObjectType* cobject,
    const Glib::RefPtr&lt;Gtk::Builder&gt;&amp; refBuilder);

  static ExampleAppWindow* create();

  void open_file_view(const Glib::RefPtr&lt;Gio::File&gt;&amp; file);

protected:
  Glib::RefPtr&lt;Gtk::Builder&gt; m_refBuilder;
};

#endif /* GTKMM_EXAMPLEAPPWINDOW_H */
</programlisting>
<para lang="en">File: <filename>exampleapplication.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "../step1/exampleapplication.h"
// Equal to the corresponding file in step1
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "../step1/main.cc"
// Equal to the corresponding file in step1
</programlisting>
<para lang="en">File: <filename>exampleapplication.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "exampleapplication.h"
#include "exampleappwindow.h"
#include &lt;iostream&gt;
#include &lt;exception&gt;

ExampleApplication::ExampleApplication()
: Gtk::Application("org.gtkmm.examples.application", Gio::APPLICATION_HANDLES_OPEN)
{
}

Glib::RefPtr&lt;ExampleApplication&gt; ExampleApplication::create()
{
  return Glib::RefPtr&lt;ExampleApplication&gt;(new ExampleApplication());
}

ExampleAppWindow* ExampleApplication::create_appwindow()
{
  auto appwindow = ExampleAppWindow::create();

  // Make sure that the application runs for as long this window is still open.
  add_window(*appwindow);

  // Gtk::Application::add_window() connects a signal handler to the window's
  // signal_hide(). That handler removes the window from the application.
  // If it's the last window to be removed, the application stops running.
  // Gtk::Window::set_application() does not connect a signal handler, but is
  // otherwise equivalent to Gtk::Application::add_window().

  // Delete the window when it is hidden.
  appwindow-&gt;signal_hide().connect(sigc::bind&lt;Gtk::Window*&gt;(sigc::mem_fun(*this,
    &amp;ExampleApplication::on_hide_window), appwindow));

  return appwindow;
}

void ExampleApplication::on_activate()
{
  try
  {
    // The application has been started, so let's show a window.
    auto appwindow = create_appwindow();
    appwindow-&gt;present();
  }
  // If create_appwindow() throws an exception (perhaps from Gtk::Builder),
  // no window has been created, no window has been added to the application,
  // and therefore the application will stop running.
  catch (const Glib::Error&amp; ex)
  {
    std::cerr &lt;&lt; "ExampleApplication::on_activate(): " &lt;&lt; ex.what() &lt;&lt; std::endl;
  }
  catch (const std::exception&amp; ex)
  {
    std::cerr &lt;&lt; "ExampleApplication::on_activate(): " &lt;&lt; ex.what() &lt;&lt; std::endl;
  }
}

void ExampleApplication::on_open(const Gio::Application::type_vec_files&amp; files,
  const Glib::ustring&amp; /* hint */)
{
  // The application has been asked to open some files,
  // so let's open a new view for each one.
  ExampleAppWindow* appwindow = nullptr;
  auto windows = get_windows();
  if (windows.size() &gt; 0)
    appwindow = dynamic_cast&lt;ExampleAppWindow*&gt;(windows[0]);

  try
  {
    if (!appwindow)
      appwindow = create_appwindow();

    for (const auto&amp; file : files)
      appwindow-&gt;open_file_view(file);

    appwindow-&gt;present();
  }
  catch (const Glib::Error&amp; ex)
  {
    std::cerr &lt;&lt; "ExampleApplication::on_open(): " &lt;&lt; ex.what() &lt;&lt; std::endl;
  }
  catch (const std::exception&amp; ex)
  {
    std::cerr &lt;&lt; "ExampleApplication::on_open(): " &lt;&lt; ex.what() &lt;&lt; std::endl;
  }
}

void ExampleApplication::on_hide_window(Gtk::Window* window)
{
  delete window;
}
</programlisting>
<para lang="en">File: <filename>exampleappwindow.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "exampleappwindow.h"
#include &lt;stdexcept&gt;

ExampleAppWindow::ExampleAppWindow(BaseObjectType* cobject,
  const Glib::RefPtr&lt;Gtk::Builder&gt;&amp; refBuilder)
: Gtk::ApplicationWindow(cobject),
  m_refBuilder(refBuilder)
{
}

//static
ExampleAppWindow* ExampleAppWindow::create()
{
  // Load the Builder file and instantiate its widgets.
  auto refBuilder = Gtk::Builder::create_from_resource("/org/gtkmm/exampleapp/window.ui");

  ExampleAppWindow* window = nullptr;
  refBuilder-&gt;get_widget_derived("app_window", window);
  if (!window)
    throw std::runtime_error("No \"app_window\" object in window.ui");

  return window;
}

void ExampleAppWindow::open_file_view(const Glib::RefPtr&lt;Gio::File&gt;&amp; /* file */)
{
}
</programlisting>
<para lang="en">File: <filename>exampleapp.gresource.xml</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
&lt;?xml version="1.0" encoding="UTF-8"?&gt;
&lt;gresources&gt;
  &lt;gresource prefix="/org/gtkmm/exampleapp"&gt;
    &lt;file preprocess="xml-stripblanks"&gt;window.ui&lt;/file&gt;
  &lt;/gresource&gt;
&lt;/gresources&gt;
</programlisting>
<para lang="en">File: <filename>window.ui</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
&lt;?xml version="1.0" encoding="UTF-8"?&gt;
&lt;interface&gt;
  &lt;!-- interface-requires gtk+ 3.8 --&gt;
  &lt;object class="GtkApplicationWindow" id="app_window"&gt;
    &lt;property name="title" translatable="yes"&gt;Example Application&lt;/property&gt;
    &lt;property name="default-width"&gt;600&lt;/property&gt;
    &lt;property name="default-height"&gt;400&lt;/property&gt;
    &lt;child&gt;
      &lt;object class="GtkBox" id="content_box"&gt;
        &lt;property name="visible"&gt;True&lt;/property&gt;
        &lt;property name="orientation"&gt;vertical&lt;/property&gt;
        &lt;child&gt;
          &lt;object class="GtkHeaderBar" id="header"&gt;
            &lt;property name="visible"&gt;True&lt;/property&gt;
            &lt;child type="title"&gt;
              &lt;object class="GtkStackSwitcher" id="tabs"&gt;
                &lt;property name="visible"&gt;True&lt;/property&gt;
                &lt;property name="stack"&gt;stack&lt;/property&gt;
              &lt;/object&gt;
            &lt;/child&gt;
          &lt;/object&gt;
        &lt;/child&gt;
        &lt;child&gt;
          &lt;object class="GtkStack" id="stack"&gt;
            &lt;property name="visible"&gt;True&lt;/property&gt;
          &lt;/object&gt;
        &lt;/child&gt;
      &lt;/object&gt;
    &lt;/child&gt;
  &lt;/object&gt;
&lt;/interface&gt;
</programlisting>
<!-- end inserted example code -->

</sect1>

<sect1 id="sec-buildapp-opening-files">
<title lang="en">Opening files</title>

<para lang="en">
In this step, we make our application show the contents of all the files that it is
given on the commandline.
</para>

<para lang="en">
To this end, we add a data member to our application window and keep a pointer to the
<classname>Gtk::Stack</classname> there. We get the pointer with a call to
<methodname>Gtk::Builder::get_widget()</methodname> in the application window's constructor.
</para>

<para lang="en">
Now we revisit the <methodname>ExampleAppWindow::open_file_view()</methodname> method
that is called for each commandline argument, and construct a <classname>Gtk::TextView</classname>
that we then add as a page to the stack.
</para>

<para lang="en">
Note that we do not have to touch the stack switcher at all. It gets all its information
from the stack that it belongs to. Here, we are passing the label to show for each file
as the last argument to the <methodname>Gtk::Stack::add()</methodname> method.
</para>

<para lang="en">
Our application is beginning to take shape:
</para>

<figure id="figure-buildapp-opening-files">
  <title lang="en">Opening files</title>
  <screenshot>
    <graphic format="PNG" fileref="figures/buildapp_opening_files.png"/>
  </screenshot>
</figure>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/buildapp/step3?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>exampleappwindow.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLEAPPWINDOW_H_
#define GTKMM_EXAMPLEAPPWINDOW_H_

#include &lt;gtkmm.h&gt;

class ExampleAppWindow : public Gtk::ApplicationWindow
{
public:
  ExampleAppWindow(BaseObjectType* cobject,
    const Glib::RefPtr&lt;Gtk::Builder&gt;&amp; refBuilder);

  static ExampleAppWindow* create();

  void open_file_view(const Glib::RefPtr&lt;Gio::File&gt;&amp; file);

protected:
  Glib::RefPtr&lt;Gtk::Builder&gt; m_refBuilder;
  Gtk::Stack* m_stack;
};

#endif /* GTKMM_EXAMPLEAPPWINDOW_H */
</programlisting>
<para lang="en">File: <filename>exampleapplication.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "../step1/exampleapplication.h"
// Equal to the corresponding file in step1
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "../step1/main.cc"
// Equal to the corresponding file in step1
</programlisting>
<para lang="en">File: <filename>exampleapplication.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "../step2/exampleapplication.cc"
// Equal to the corresponding file in step2
</programlisting>
<para lang="en">File: <filename>exampleappwindow.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "exampleappwindow.h"
#include &lt;iostream&gt;
#include &lt;stdexcept&gt;

ExampleAppWindow::ExampleAppWindow(BaseObjectType* cobject,
  const Glib::RefPtr&lt;Gtk::Builder&gt;&amp; refBuilder)
: Gtk::ApplicationWindow(cobject),
  m_refBuilder(refBuilder),
  m_stack(nullptr)
{
  m_refBuilder-&gt;get_widget("stack", m_stack);
  if (!m_stack)
    throw std::runtime_error("No \"stack\" object in window.ui");
}

//static
ExampleAppWindow* ExampleAppWindow::create()
{
  // Load the Builder file and instantiate its widgets.
  auto refBuilder = Gtk::Builder::create_from_resource("/org/gtkmm/exampleapp/window.ui");

  ExampleAppWindow* window = nullptr;
  refBuilder-&gt;get_widget_derived("app_window", window);
  if (!window)
    throw std::runtime_error("No \"app_window\" object in window.ui");

  return window;
}

void ExampleAppWindow::open_file_view(const Glib::RefPtr&lt;Gio::File&gt;&amp; file)
{
  const auto basename = file-&gt;get_basename();

  auto scrolled = Gtk::manage(new Gtk::ScrolledWindow());
  scrolled-&gt;set_hexpand(true);
  scrolled-&gt;set_vexpand(true);
  scrolled-&gt;show();
  auto view = Gtk::manage(new Gtk::TextView());
  view-&gt;set_editable(false);
  view-&gt;set_cursor_visible(false);
  view-&gt;show();
  scrolled-&gt;add(*view);
  m_stack-&gt;add(*scrolled, basename, basename);

  try
  {
    char* contents = nullptr;
    gsize length = 0;
    
    file-&gt;load_contents(contents, length);
    view-&gt;get_buffer()-&gt;set_text(contents, contents+length);
    g_free(contents);
  }
  catch (const Glib::Error&amp; ex)
  {
    std::cout &lt;&lt; "ExampleAppWindow::open_file_view(\"" &lt;&lt; file-&gt;get_parse_name()
      &lt;&lt; "\"):\n  " &lt;&lt; ex.what() &lt;&lt; std::endl;
  }
}
</programlisting>
<!-- end inserted example code -->

</sect1>

<sect1 id="sec-buildapp-app-menu">
<title lang="en">An application menu</title>

<para lang="en">
An application menu is shown by GNOME shell at the top of the screen. It is meant
to collect infrequently used actions that affect the whole application.
The application menu is shown either at the top of the screen, or at the top of
the application's window, depending on which desktop shell you use.
</para>

<para lang="en">
Just like the application window, we specify our application menu in a ui file,
and add it as a resource to our binary.
</para>

<para lang="en">
To associate the app menu with the application, we have to call
<methodname>Gtk::Application::set_app_menu()</methodname>. Since app menus work by
activating <classname>Gio::Action</classname>s, we also have to add a suitable set of
actions to our application.
</para>

<para lang="en">
Both of these tasks are best done in the <methodname>on_startup()</methodname> default
signal handler, which is guaranteed to be called once for each primary application instance.
</para>

<para lang="en">
Our preferences menu item does not do anything yet, but the Quit menu item is fully
functional. It can also be activated by the usual Ctrl-Q shortcut. The shortcut
is added with <methodname>Gtk::Application::set_accel_for_action()</methodname>.
</para>

<para lang="en">
The application menu looks like this:
</para>

<figure id="figure-buildapp-app-menu">
  <title lang="en">An application menu</title>
  <screenshot>
    <graphic format="PNG" fileref="figures/buildapp_app_menu.png"/>
  </screenshot>
</figure>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/buildapp/step4?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>exampleappwindow.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "../step3/exampleappwindow.h"
// Equal to the corresponding file in step3
</programlisting>
<para lang="en">File: <filename>exampleapplication.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLEAPPLICATION_H
#define GTKMM_EXAMPLEAPPLICATION_H

#include &lt;gtkmm.h&gt;

class ExampleAppWindow;

class ExampleApplication: public Gtk::Application
{
protected:
  ExampleApplication();

public:
  static Glib::RefPtr&lt;ExampleApplication&gt; create();

protected:
  // Override default signal handlers:
  void on_startup() override;
  void on_activate() override;
  void on_open(const Gio::Application::type_vec_files&amp; files,
    const Glib::ustring&amp; hint) override;

private:
  ExampleAppWindow* create_appwindow();
  void on_hide_window(Gtk::Window* window);
  void on_action_preferences();
  void on_action_quit();
};

#endif /* GTKMM_EXAMPLEAPPLICATION_H */
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "../step1/main.cc"
// Equal to the corresponding file in step1
</programlisting>
<para lang="en">File: <filename>exampleapplication.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "exampleapplication.h"
#include "exampleappwindow.h"
#include &lt;iostream&gt;
#include &lt;exception&gt;

ExampleApplication::ExampleApplication()
: Gtk::Application("org.gtkmm.examples.application", Gio::APPLICATION_HANDLES_OPEN)
{
}

Glib::RefPtr&lt;ExampleApplication&gt; ExampleApplication::create()
{
  return Glib::RefPtr&lt;ExampleApplication&gt;(new ExampleApplication());
}

ExampleAppWindow* ExampleApplication::create_appwindow()
{
  auto appwindow = ExampleAppWindow::create();

  // Make sure that the application runs for as long this window is still open.
  add_window(*appwindow);

  // Gtk::Application::add_window() connects a signal handler to the window's
  // signal_hide(). That handler removes the window from the application.
  // If it's the last window to be removed, the application stops running.
  // Gtk::Window::set_application() does not connect a signal handler, but is
  // otherwise equivalent to Gtk::Application::add_window().

  // Delete the window when it is hidden.
  appwindow-&gt;signal_hide().connect(sigc::bind&lt;Gtk::Window*&gt;(sigc::mem_fun(*this,
    &amp;ExampleApplication::on_hide_window), appwindow));

  return appwindow;
}

void ExampleApplication::on_startup()
{
  // Call the base class's implementation.
  Gtk::Application::on_startup();

  // Add actions and keyboard accelerators for the application menu.
  add_action("preferences", sigc::mem_fun(*this, &amp;ExampleApplication::on_action_preferences));
  add_action("quit", sigc::mem_fun(*this, &amp;ExampleApplication::on_action_quit));
  set_accel_for_action("app.quit", "&lt;Ctrl&gt;Q");

  auto refBuilder = Gtk::Builder::create();
  try
  {
    refBuilder-&gt;add_from_resource("/org/gtkmm/exampleapp/app_menu.ui");
  }
  catch (const Glib::Error&amp; ex)
  {
    std::cerr &lt;&lt; "ExampleApplication::on_startup(): " &lt;&lt; ex.what() &lt;&lt; std::endl;
    return;
  }

  auto object = refBuilder-&gt;get_object("appmenu");
  auto app_menu = Glib::RefPtr&lt;Gio::MenuModel&gt;::cast_dynamic(object);
  if (app_menu)
    set_app_menu(app_menu);
  else
    std::cerr &lt;&lt; "ExampleApplication::on_startup(): No \"appmenu\" object in app_menu.ui"
              &lt;&lt; std::endl;
}

void ExampleApplication::on_activate()
{
  try
  {
    // The application has been started, so let's show a window.
    auto appwindow = create_appwindow();
    appwindow-&gt;present();
  }
  // If create_appwindow() throws an exception (perhaps from Gtk::Builder),
  // no window has been created, no window has been added to the application,
  // and therefore the application will stop running.
  catch (const Glib::Error&amp; ex)
  {
    std::cerr &lt;&lt; "ExampleApplication::on_activate(): " &lt;&lt; ex.what() &lt;&lt; std::endl;
  }
  catch (const std::exception&amp; ex)
  {
    std::cerr &lt;&lt; "ExampleApplication::on_activate(): " &lt;&lt; ex.what() &lt;&lt; std::endl;
  }
}

void ExampleApplication::on_open(const Gio::Application::type_vec_files&amp; files,
  const Glib::ustring&amp; /* hint */)
{
  // The application has been asked to open some files,
  // so let's open a new view for each one.
  ExampleAppWindow* appwindow = nullptr;
  auto windows = get_windows();
  if (windows.size() &gt; 0)
    appwindow = dynamic_cast&lt;ExampleAppWindow*&gt;(windows[0]);

  try
  {
    if (!appwindow)
      appwindow = create_appwindow();

    for (const auto&amp; file : files)
      appwindow-&gt;open_file_view(file);

    appwindow-&gt;present();
  }
  catch (const Glib::Error&amp; ex)
  {
    std::cerr &lt;&lt; "ExampleApplication::on_open(): " &lt;&lt; ex.what() &lt;&lt; std::endl;
  }
  catch (const std::exception&amp; ex)
  {
    std::cerr &lt;&lt; "ExampleApplication::on_open(): " &lt;&lt; ex.what() &lt;&lt; std::endl;
  }
}

void ExampleApplication::on_hide_window(Gtk::Window* window)
{
  delete window;
}

void ExampleApplication::on_action_preferences()
{

}

void ExampleApplication::on_action_quit()
{
  // Gio::Application::quit() will make Gio::Application::run() return,
  // but it's a crude way of ending the program. The window is not removed
  // from the application. Neither the window's nor the application's
  // destructors will be called, because there will be remaining reference
  // counts in both of them. If we want the destructors to be called, we
  // must remove the window from the application. One way of doing this
  // is to hide the window. See comment in create_appwindow().
  auto windows = get_windows();
  for (auto window : windows)
    window-&gt;hide();

  // Not really necessary, when Gtk::Widget::hide() is called, unless
  // Gio::Application::hold() has been called without a corresponding call
  // to Gio::Application::release().
  quit();
}
</programlisting>
<para lang="en">File: <filename>exampleappwindow.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "../step3/exampleappwindow.cc"
// Equal to the corresponding file in step3
</programlisting>
<para lang="en">File: <filename>exampleapp.gresource.xml</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
&lt;?xml version="1.0" encoding="UTF-8"?&gt;
&lt;gresources&gt;
  &lt;gresource prefix="/org/gtkmm/exampleapp"&gt;
    &lt;file preprocess="xml-stripblanks"&gt;window.ui&lt;/file&gt;
    &lt;file preprocess="xml-stripblanks"&gt;app_menu.ui&lt;/file&gt;
  &lt;/gresource&gt;
&lt;/gresources&gt;
</programlisting>
<para lang="en">File: <filename>app_menu.ui</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
&lt;?xml version="1.0"?&gt;
&lt;interface&gt;
  &lt;!-- interface-requires gtk+ 3.0 --&gt;
  &lt;menu id="appmenu"&gt;
    &lt;section&gt;
      &lt;item&gt;
        &lt;attribute name="label" translatable="yes"&gt;_Preferences&lt;/attribute&gt;
        &lt;attribute name="action"&gt;app.preferences&lt;/attribute&gt;
      &lt;/item&gt;
    &lt;/section&gt;
    &lt;section&gt;
      &lt;item&gt;
        &lt;attribute name="label" translatable="yes"&gt;_Quit&lt;/attribute&gt;
        &lt;attribute name="action"&gt;app.quit&lt;/attribute&gt;
      &lt;/item&gt;
    &lt;/section&gt;
  &lt;/menu&gt;
&lt;/interface&gt;
</programlisting>
<!-- end inserted example code -->

</sect1>

<sect1 id="sec-buildapp-pref-dialog">
<title lang="en">A preference dialog</title>

<para lang="en">
A typical application will have some preferences that should be remembered from one run
to the next. Even for our simple example application, we may want to change the font
that is used for the content.
</para>

<para lang="en">
We are going to use <classname>Gio::Settings</classname> to store our preferences.
<classname>Gio::Settings</classname> requires a schema that describes our settings,
in our case the <filename>org.gtkmm.exampleapp.gschema.xml</filename> file.
</para>

<para lang="en">
Before we can make use of this schema in our application, we need to compile it into
the binary form that <classname>Gio::Settings</classname> expects. GIO provides macros
to do this in autotools-based projects. See the description of
<ulink url="https://developer.gnome.org/gio/stable/GSettings.html">GSettings</ulink>.
</para>

<para lang="en">
Next, we need to connect our settings to the widgets that they are supposed to control.
One convenient way to do this is to use <methodname>Gio::Settings::bind()</methodname>
to bind settings keys to object properties, as we do for the transition setting in
<classname>ExampleAppWindow</classname>'s constructor.
<programlisting lang="en">
<![CDATA[m_settings = Gio::Settings::create("org.gtkmm.exampleapp");
m_settings->bind("transition", m_stack->property_transition_type());]]>
</programlisting>
</para>

<para lang="en">
The code to connect the font setting is a little more involved, since it corresponds to
an object property in a <classname>Gtk::TextTag</classname> that we must first create.
The code is in <methodname>ExampleAppWindow::open_file_view()</methodname>.
<programlisting lang="en">
<![CDATA[auto tag = buffer->create_tag();
m_settings->bind("font", tag->property_font());
buffer->apply_tag(tag, buffer->begin(), buffer->end());]]>
</programlisting>
</para>

<para lang="en">
At this point, the application will already react if you change one of the settings,
e.g. using the <command>gsettings</command> commandline tool. Of course, we expect
the application to provide a preference dialog for these. So lets do that now.
Our preference dialog will be a subclass of <classname>Gtk::Dialog</classname>, and
we'll use the same techniques that we've already seen in <classname>ExampleAppWindow</classname>:
a <classname>Gtk::Builder</classname> ui file and settings bindings.
</para>

<para lang="en">
When we've created the <filename>prefs.ui</filename> file and the <classname>ExampleAppPrefs</classname>
class, we revisit the <methodname>ExampleApplication::on_action_preferences()</methodname>
method in our application class, and make it open a new preference dialog.
<programlisting lang="en">
<![CDATA[auto prefs_dialog = ExampleAppPrefs::create(*get_active_window());
prefs_dialog->present();]]>
</programlisting>
</para>

<para lang="en">
After all this work, our application can now show a preference dialog like this:
</para>

<figure id="figure-buildapp-pref-dialog">
  <title lang="en">An preference dialog</title>
  <screenshot>
    <graphic format="PNG" fileref="figures/buildapp_pref_dialog.png"/>
  </screenshot>
</figure>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/buildapp/step5?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>exampleappprefs.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLEAPPPREFS_H_
#define GTKMM_EXAMPLEAPPPREFS_H_

#include &lt;gtkmm.h&gt;

class ExampleAppPrefs : public Gtk::Dialog
{
public:
  ExampleAppPrefs(BaseObjectType* cobject,
    const Glib::RefPtr&lt;Gtk::Builder&gt;&amp; refBuilder);

  static ExampleAppPrefs* create(Gtk::Window&amp; parent);

protected:
  Glib::RefPtr&lt;Gtk::Builder&gt; m_refBuilder;
  Glib::RefPtr&lt;Gio::Settings&gt; m_settings;
  Gtk::FontButton* m_font;
  Gtk::ComboBoxText* m_transition;
};

#endif /* GTKMM_EXAMPLEAPPPREFS_H_ */
</programlisting>
<para lang="en">File: <filename>exampleappwindow.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLEAPPWINDOW_H_
#define GTKMM_EXAMPLEAPPWINDOW_H_

#include &lt;gtkmm.h&gt;

class ExampleAppWindow : public Gtk::ApplicationWindow
{
public:
  ExampleAppWindow(BaseObjectType* cobject,
    const Glib::RefPtr&lt;Gtk::Builder&gt;&amp; refBuilder);

  static ExampleAppWindow* create();

  void open_file_view(const Glib::RefPtr&lt;Gio::File&gt;&amp; file);

protected:
  Glib::RefPtr&lt;Gtk::Builder&gt; m_refBuilder;
  Glib::RefPtr&lt;Gio::Settings&gt; m_settings;
  Gtk::Stack* m_stack;
};

#endif /* GTKMM_EXAMPLEAPPWINDOW_H */
</programlisting>
<para lang="en">File: <filename>exampleapplication.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "../step4/exampleapplication.h"
// Equal to the corresponding file in step4
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "exampleapplication.h"

int main(int argc, char* argv[])
{
  // Since this example is running uninstalled, we have to help it find its
  // schema. This is *not* necessary in a properly installed application.
  Glib::setenv ("GSETTINGS_SCHEMA_DIR", ".", false);

  auto application = ExampleApplication::create();

  // Start the application, showing the initial window,
  // and opening extra views for any files that it is asked to open,
  // for instance as a command-line parameter.
  // run() will return when the last window has been closed.
  return application-&gt;run(argc, argv);
}
</programlisting>
<para lang="en">File: <filename>exampleappprefs.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "exampleappprefs.h"
#include "exampleappwindow.h"
#include &lt;stdexcept&gt;

ExampleAppPrefs::ExampleAppPrefs(BaseObjectType* cobject,
  const Glib::RefPtr&lt;Gtk::Builder&gt;&amp; refBuilder)
: Gtk::Dialog(cobject),
  m_refBuilder(refBuilder),
  m_settings(),
  m_font(nullptr),
  m_transition(nullptr)
{
  m_refBuilder-&gt;get_widget("font", m_font);
  if (!m_font)
    throw std::runtime_error("No \"font\" object in prefs.ui");

  m_refBuilder-&gt;get_widget("transition", m_transition);
  if (!m_transition)
    throw std::runtime_error("No \"transition\" object in prefs.ui");

  m_settings = Gio::Settings::create("org.gtkmm.exampleapp");
  m_settings-&gt;bind("font", m_font-&gt;property_font_name());
  m_settings-&gt;bind("transition", m_transition-&gt;property_active_id());
}

//static
ExampleAppPrefs* ExampleAppPrefs::create(Gtk::Window&amp; parent)
{
  // Load the Builder file and instantiate its widgets.
  auto refBuilder = Gtk::Builder::create_from_resource("/org/gtkmm/exampleapp/prefs.ui");

  ExampleAppPrefs* dialog = nullptr;
  refBuilder-&gt;get_widget_derived("prefs_dialog", dialog);
  if (!dialog)
    throw std::runtime_error("No \"prefs_dialog\" object in prefs.ui");

  dialog-&gt;set_transient_for(parent);

  return dialog;
}
</programlisting>
<para lang="en">File: <filename>exampleapplication.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "exampleapplication.h"
#include "exampleappwindow.h"
#include "exampleappprefs.h"
#include &lt;iostream&gt;
#include &lt;exception&gt;

ExampleApplication::ExampleApplication()
: Gtk::Application("org.gtkmm.examples.application", Gio::APPLICATION_HANDLES_OPEN)
{
}

Glib::RefPtr&lt;ExampleApplication&gt; ExampleApplication::create()
{
  return Glib::RefPtr&lt;ExampleApplication&gt;(new ExampleApplication());
}

ExampleAppWindow* ExampleApplication::create_appwindow()
{
  auto appwindow = ExampleAppWindow::create();

  // Make sure that the application runs for as long this window is still open.
  add_window(*appwindow);

  // Gtk::Application::add_window() connects a signal handler to the window's
  // signal_hide(). That handler removes the window from the application.
  // If it's the last window to be removed, the application stops running.
  // Gtk::Window::set_application() does not connect a signal handler, but is
  // otherwise equivalent to Gtk::Application::add_window().

  // Delete the window when it is hidden.
  appwindow-&gt;signal_hide().connect(sigc::bind&lt;Gtk::Window*&gt;(sigc::mem_fun(*this,
    &amp;ExampleApplication::on_hide_window), appwindow));

  return appwindow;
}

void ExampleApplication::on_startup()
{
  // Call the base class's implementation.
  Gtk::Application::on_startup();

  // Add actions and keyboard accelerators for the application menu.
  add_action("preferences", sigc::mem_fun(*this, &amp;ExampleApplication::on_action_preferences));
  add_action("quit", sigc::mem_fun(*this, &amp;ExampleApplication::on_action_quit));
  set_accel_for_action("app.quit", "&lt;Ctrl&gt;Q");

  auto refBuilder = Gtk::Builder::create();
  try
  {
    refBuilder-&gt;add_from_resource("/org/gtkmm/exampleapp/app_menu.ui");
  }
  catch (const Glib::Error&amp; ex)
  {
    std::cerr &lt;&lt; "ExampleApplication::on_startup(): " &lt;&lt; ex.what() &lt;&lt; std::endl;
    return;
  }

  auto object = refBuilder-&gt;get_object("appmenu");
  auto app_menu = Glib::RefPtr&lt;Gio::MenuModel&gt;::cast_dynamic(object);
  if (app_menu)
    set_app_menu(app_menu);
  else
    std::cerr &lt;&lt; "ExampleApplication::on_startup(): No \"appmenu\" object in app_menu.ui"
              &lt;&lt; std::endl;
}

void ExampleApplication::on_activate()
{
  try
  {
    // The application has been started, so let's show a window.
    auto appwindow = create_appwindow();
    appwindow-&gt;present();
  }
  // If create_appwindow() throws an exception (perhaps from Gtk::Builder),
  // no window has been created, no window has been added to the application,
  // and therefore the application will stop running.
  catch (const Glib::Error&amp; ex)
  {
    std::cerr &lt;&lt; "ExampleApplication::on_activate(): " &lt;&lt; ex.what() &lt;&lt; std::endl;
  }
  catch (const std::exception&amp; ex)
  {
    std::cerr &lt;&lt; "ExampleApplication::on_activate(): " &lt;&lt; ex.what() &lt;&lt; std::endl;
  }
}

void ExampleApplication::on_open(const Gio::Application::type_vec_files&amp; files,
  const Glib::ustring&amp; /* hint */)
{
  // The application has been asked to open some files,
  // so let's open a new view for each one.
  ExampleAppWindow* appwindow = nullptr;
  auto windows = get_windows();
  if (windows.size() &gt; 0)
    appwindow = dynamic_cast&lt;ExampleAppWindow*&gt;(windows[0]);

  try
  {
    if (!appwindow)
      appwindow = create_appwindow();

    for (const auto&amp; file : files)
      appwindow-&gt;open_file_view(file);

    appwindow-&gt;present();
  }
  catch (const Glib::Error&amp; ex)
  {
    std::cerr &lt;&lt; "ExampleApplication::on_open(): " &lt;&lt; ex.what() &lt;&lt; std::endl;
  }
  catch (const std::exception&amp; ex)
  {
    std::cerr &lt;&lt; "ExampleApplication::on_open(): " &lt;&lt; ex.what() &lt;&lt; std::endl;
  }
}

void ExampleApplication::on_hide_window(Gtk::Window* window)
{
  delete window;
}

void ExampleApplication::on_action_preferences()
{
  try
  {
    auto prefs_dialog = ExampleAppPrefs::create(*get_active_window());
    prefs_dialog-&gt;present();

    // Delete the dialog when it is hidden.
    prefs_dialog-&gt;signal_hide().connect(sigc::bind&lt;Gtk::Window*&gt;(sigc::mem_fun(*this,
      &amp;ExampleApplication::on_hide_window), prefs_dialog));
  }
  catch (const Glib::Error&amp; ex)
  {
    std::cerr &lt;&lt; "ExampleApplication::on_action_preferences(): " &lt;&lt; ex.what() &lt;&lt; std::endl;
  }
  catch (const std::exception&amp; ex)
  {
    std::cerr &lt;&lt; "ExampleApplication::on_action_preferences(): " &lt;&lt; ex.what() &lt;&lt; std::endl;
  }
}

void ExampleApplication::on_action_quit()
{
  // Gio::Application::quit() will make Gio::Application::run() return,
  // but it's a crude way of ending the program. The window is not removed
  // from the application. Neither the window's nor the application's
  // destructors will be called, because there will be remaining reference
  // counts in both of them. If we want the destructors to be called, we
  // must remove the window from the application. One way of doing this
  // is to hide the window. See comment in create_appwindow().
  auto windows = get_windows();
  for (auto window : windows)
    window-&gt;hide();

  // Not really necessary, when Gtk::Widget::hide() is called, unless
  // Gio::Application::hold() has been called without a corresponding call
  // to Gio::Application::release().
  quit();
}
</programlisting>
<para lang="en">File: <filename>exampleappwindow.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "exampleappwindow.h"
#include &lt;iostream&gt;
#include &lt;stdexcept&gt;

ExampleAppWindow::ExampleAppWindow(BaseObjectType* cobject,
  const Glib::RefPtr&lt;Gtk::Builder&gt;&amp; refBuilder)
: Gtk::ApplicationWindow(cobject),
  m_refBuilder(refBuilder),
  m_settings(),
  m_stack(nullptr)
{
  m_refBuilder-&gt;get_widget("stack", m_stack);
  if (!m_stack)
    throw std::runtime_error("No \"stack\" object in window.ui");

  m_settings = Gio::Settings::create("org.gtkmm.exampleapp");
  m_settings-&gt;bind("transition", m_stack-&gt;property_transition_type());
}

//static
ExampleAppWindow* ExampleAppWindow::create()
{
  // Load the Builder file and instantiate its widgets.
  auto refBuilder = Gtk::Builder::create_from_resource("/org/gtkmm/exampleapp/window.ui");

  ExampleAppWindow* window = nullptr;
  refBuilder-&gt;get_widget_derived("app_window", window);
  if (!window)
    throw std::runtime_error("No \"app_window\" object in window.ui");

  return window;
}

void ExampleAppWindow::open_file_view(const Glib::RefPtr&lt;Gio::File&gt;&amp; file)
{
  const auto basename = file-&gt;get_basename();

  auto scrolled = Gtk::manage(new Gtk::ScrolledWindow());
  scrolled-&gt;set_hexpand(true);
  scrolled-&gt;set_vexpand(true);
  scrolled-&gt;show();
  auto view = Gtk::manage(new Gtk::TextView());
  view-&gt;set_editable(false);
  view-&gt;set_cursor_visible(false);
  view-&gt;show();
  scrolled-&gt;add(*view);
  m_stack-&gt;add(*scrolled, basename, basename);

  auto buffer = view-&gt;get_buffer();
  try
  {
    char* contents = nullptr;
    gsize length = 0;
    
    file-&gt;load_contents(contents, length);
    buffer-&gt;set_text(contents, contents+length);
    g_free(contents);
  }
  catch (const Glib::Error&amp; ex)
  {
    std::cout &lt;&lt; "ExampleAppWindow::open_file_view(\"" &lt;&lt; file-&gt;get_parse_name()
      &lt;&lt; "\"):\n  " &lt;&lt; ex.what() &lt;&lt; std::endl;
  }

  auto tag = buffer-&gt;create_tag();
  m_settings-&gt;bind("font", tag-&gt;property_font());
  buffer-&gt;apply_tag(tag, buffer-&gt;begin(), buffer-&gt;end());
}
</programlisting>
<para lang="en">File: <filename>exampleapp.gresource.xml</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
&lt;?xml version="1.0" encoding="UTF-8"?&gt;
&lt;gresources&gt;
  &lt;gresource prefix="/org/gtkmm/exampleapp"&gt;
    &lt;file preprocess="xml-stripblanks"&gt;window.ui&lt;/file&gt;
    &lt;file preprocess="xml-stripblanks"&gt;app_menu.ui&lt;/file&gt;
    &lt;file preprocess="xml-stripblanks"&gt;prefs.ui&lt;/file&gt;
  &lt;/gresource&gt;
&lt;/gresources&gt;
</programlisting>
<para lang="en">File: <filename>prefs.ui</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
&lt;?xml version="1.0" encoding="UTF-8"?&gt;
&lt;interface&gt;
  &lt;!-- interface-requires gtk+ 3.8 --&gt;
  &lt;object class="GtkDialog" id="prefs_dialog"&gt;
    &lt;property name="title" translatable="yes"&gt;Preferences&lt;/property&gt;
    &lt;property name="resizable"&gt;False&lt;/property&gt;
    &lt;property name="modal"&gt;True&lt;/property&gt;
    &lt;property name="use-header-bar"&gt;1&lt;/property&gt;
    &lt;child internal-child="vbox"&gt;
      &lt;object class="GtkBox" id="vbox"&gt;
        &lt;child&gt;
          &lt;object class="GtkGrid" id="grid"&gt;
            &lt;property name="visible"&gt;True&lt;/property&gt;
            &lt;property name="margin"&gt;6&lt;/property&gt;
            &lt;property name="row-spacing"&gt;12&lt;/property&gt;
            &lt;property name="column-spacing"&gt;6&lt;/property&gt;
            &lt;child&gt;
              &lt;object class="GtkLabel" id="fontlabel"&gt;
                &lt;property name="visible"&gt;True&lt;/property&gt;
                &lt;property name="label"&gt;_Font:&lt;/property&gt;
                &lt;property name="use-underline"&gt;True&lt;/property&gt;
                &lt;property name="mnemonic-widget"&gt;font&lt;/property&gt;
                &lt;property name="xalign"&gt;1&lt;/property&gt;
              &lt;/object&gt;
              &lt;packing&gt;
                &lt;property name="left-attach"&gt;0&lt;/property&gt;
                &lt;property name="top-attach"&gt;0&lt;/property&gt;
              &lt;/packing&gt;
            &lt;/child&gt;
            &lt;child&gt;
              &lt;object class="GtkFontButton" id="font"&gt;
                &lt;property name="visible"&gt;True&lt;/property&gt;
              &lt;/object&gt;
              &lt;packing&gt;
                &lt;property name="left-attach"&gt;1&lt;/property&gt;
                &lt;property name="top-attach"&gt;0&lt;/property&gt;
              &lt;/packing&gt;
            &lt;/child&gt;
            &lt;child&gt;
              &lt;object class="GtkLabel" id="transitionlabel"&gt;
                &lt;property name="visible"&gt;True&lt;/property&gt;
                &lt;property name="label"&gt;_Transition:&lt;/property&gt;
                &lt;property name="use-underline"&gt;True&lt;/property&gt;
                &lt;property name="mnemonic-widget"&gt;transition&lt;/property&gt;
                &lt;property name="xalign"&gt;1&lt;/property&gt;
              &lt;/object&gt;
              &lt;packing&gt;
                &lt;property name="left-attach"&gt;0&lt;/property&gt;
                &lt;property name="top-attach"&gt;1&lt;/property&gt;
              &lt;/packing&gt;
            &lt;/child&gt;
            &lt;child&gt;
              &lt;object class="GtkComboBoxText" id="transition"&gt;
                &lt;property name="visible"&gt;True&lt;/property&gt;
                &lt;items&gt;
                  &lt;item translatable="yes" id="none"&gt;None&lt;/item&gt;
                  &lt;item translatable="yes" id="crossfade"&gt;Fade&lt;/item&gt;
                  &lt;item translatable="yes" id="slide-left-right"&gt;Slide&lt;/item&gt;
                &lt;/items&gt;
              &lt;/object&gt;
              &lt;packing&gt;
                &lt;property name="left-attach"&gt;1&lt;/property&gt;
                &lt;property name="top-attach"&gt;1&lt;/property&gt;
              &lt;/packing&gt;
            &lt;/child&gt;
          &lt;/object&gt;
        &lt;/child&gt;
      &lt;/object&gt;
    &lt;/child&gt;
  &lt;/object&gt;
&lt;/interface&gt;
</programlisting>
<para lang="en">File: <filename>org.gtkmm.exampleapp.gschema.xml</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
&lt;?xml version="1.0" encoding="UTF-8"?&gt;
&lt;schemalist&gt;
  &lt;schema path="/org/gtkmm/exampleapp/" id="org.gtkmm.exampleapp"&gt;
    &lt;key name="font" type="s"&gt;
      &lt;default&gt;'Monospace 12'&lt;/default&gt;
      &lt;summary&gt;Font&lt;/summary&gt;
      &lt;description&gt;The font to be used for content.&lt;/description&gt;
    &lt;/key&gt;
    &lt;key name="transition" type="s"&gt;
      &lt;choices&gt;
        &lt;choice value='none'/&gt;
        &lt;choice value='crossfade'/&gt;
        &lt;choice value='slide-left-right'/&gt;
      &lt;/choices&gt;
      &lt;default&gt;'none'&lt;/default&gt;
      &lt;summary&gt;Transition&lt;/summary&gt;
      &lt;description&gt;The transition to use when switching tabs.&lt;/description&gt;
    &lt;/key&gt;
  &lt;/schema&gt;
&lt;/schemalist&gt;
</programlisting>
<!-- end inserted example code -->

</sect1>

<sect1 id="sec-buildapp-search-bar">
<title lang="en">Adding a search bar</title>

<para lang="en">
We continue to flesh out the functionality of our application. For now, we add search.
<application>gtkmm</application> supports this with <classname>Gtk::SearchEntry</classname> and <classname>Gtk::SearchBar</classname>.
The search bar is a widget that can slide in from the top to present a search entry.
</para>

<para lang="en">
We add a toggle button to the header bar, which can be used to slide out the search bar
below the header bar. The new widgets are added in the <filename>window.ui</filename> file.
</para>

<para lang="en">
Implementing the search needs quite a few code changes that we are not going to completely
go over here. The central piece of the search implementation is a signal handler that
listens for text changes in the search entry, shown here without error handling.
<programlisting lang="en">
<![CDATA[void ExampleAppWindow::on_search_text_changed()
{
  const auto text = m_searchentry->get_text();
  auto tab = dynamic_cast<Gtk::ScrolledWindow*>(m_stack->get_visible_child());
  auto view = dynamic_cast<Gtk::TextView*>(tab->get_child());

  // Very simple-minded search implementation.
  auto buffer = view->get_buffer();
  Gtk::TextIter match_start;
  Gtk::TextIter match_end;
  if (buffer->begin().forward_search(text, Gtk::TEXT_SEARCH_CASE_INSENSITIVE,
      match_start, match_end))
  {
    buffer->select_range(match_start, match_end);
    view->scroll_to(match_start);
  }
}]]>
</programlisting>
</para>

<para lang="en">
With the search bar, our application now looks like this:
</para>

<figure id="figure-buildapp-search-bar">
  <title lang="en">Adding a search bar</title>
  <screenshot>
    <graphic format="PNG" fileref="figures/buildapp_search_bar.png"/>
  </screenshot>
</figure>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/buildapp/step6?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>exampleappprefs.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "../step5/exampleappprefs.h"
// Equal to the corresponding file in step5
</programlisting>
<para lang="en">File: <filename>exampleappwindow.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLEAPPWINDOW_H_
#define GTKMM_EXAMPLEAPPWINDOW_H_

#include &lt;gtkmm.h&gt;

class ExampleAppWindow : public Gtk::ApplicationWindow
{
public:
  ExampleAppWindow(BaseObjectType* cobject,
    const Glib::RefPtr&lt;Gtk::Builder&gt;&amp; refBuilder);

  static ExampleAppWindow* create();

  void open_file_view(const Glib::RefPtr&lt;Gio::File&gt;&amp; file);

protected:
  // Signal handlers
  void on_search_text_changed();
  void on_visible_child_changed();

  Glib::RefPtr&lt;Gtk::Builder&gt; m_refBuilder;
  Glib::RefPtr&lt;Gio::Settings&gt; m_settings;
  Gtk::Stack* m_stack;
  Gtk::ToggleButton* m_search;
  Gtk::SearchBar* m_searchbar;
  Gtk::SearchEntry* m_searchentry;
  Glib::RefPtr&lt;Glib::Binding&gt; m_prop_binding;
};

#endif /* GTKMM_EXAMPLEAPPWINDOW_H */
</programlisting>
<para lang="en">File: <filename>exampleapplication.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "../step4/exampleapplication.h"
// Equal to the corresponding file in step4
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "../step5/main.cc"
// Equal to the corresponding file in step5
</programlisting>
<para lang="en">File: <filename>exampleappprefs.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "../step5/exampleappprefs.cc"
// Equal to the corresponding file in step5
</programlisting>
<para lang="en">File: <filename>exampleapplication.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "../step5/exampleapplication.cc"
// Equal to the corresponding file in step5
</programlisting>
<para lang="en">File: <filename>exampleappwindow.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "exampleappwindow.h"
#include &lt;iostream&gt;
#include &lt;stdexcept&gt;

ExampleAppWindow::ExampleAppWindow(BaseObjectType* cobject,
  const Glib::RefPtr&lt;Gtk::Builder&gt;&amp; refBuilder)
: Gtk::ApplicationWindow(cobject),
  m_refBuilder(refBuilder),
  m_settings(),
  m_stack(nullptr),
  m_search(nullptr),
  m_searchbar(nullptr),
  m_searchentry(nullptr),
  m_prop_binding()
{
  m_refBuilder-&gt;get_widget("stack", m_stack);
  if (!m_stack)
    throw std::runtime_error("No \"stack\" object in window.ui");

  m_refBuilder-&gt;get_widget("search", m_search);
  if (!m_search)
    throw std::runtime_error("No \"search\" object in window.ui");

  m_refBuilder-&gt;get_widget("searchbar", m_searchbar);
  if (!m_searchbar)
    throw std::runtime_error("No \"searchbar\" object in window.ui");

  m_refBuilder-&gt;get_widget("searchentry", m_searchentry);
  if (!m_searchentry)
    throw std::runtime_error("No \"searchentry\" object in window.ui");

  m_settings = Gio::Settings::create("org.gtkmm.exampleapp");
  m_settings-&gt;bind("transition", m_stack-&gt;property_transition_type());

  m_prop_binding = Glib::Binding::bind_property(m_search-&gt;property_active(),
    m_searchbar-&gt;property_search_mode_enabled(), Glib::BINDING_BIDIRECTIONAL);

  // Connect signal handlers.
  m_searchentry-&gt;signal_search_changed().connect(
    sigc::mem_fun(*this, &amp;ExampleAppWindow::on_search_text_changed));
  m_stack-&gt;property_visible_child().signal_changed().connect(
    sigc::mem_fun(*this, &amp;ExampleAppWindow::on_visible_child_changed));
}

//static
ExampleAppWindow* ExampleAppWindow::create()
{
  // Load the Builder file and instantiate its widgets.
  auto refBuilder = Gtk::Builder::create_from_resource("/org/gtkmm/exampleapp/window.ui");

  ExampleAppWindow* window = nullptr;
  refBuilder-&gt;get_widget_derived("app_window", window);
  if (!window)
    throw std::runtime_error("No \"app_window\" object in window.ui");

  return window;
}

void ExampleAppWindow::open_file_view(const Glib::RefPtr&lt;Gio::File&gt;&amp; file)
{
  const auto basename = file-&gt;get_basename();

  auto scrolled = Gtk::manage(new Gtk::ScrolledWindow());
  scrolled-&gt;set_hexpand(true);
  scrolled-&gt;set_vexpand(true);
  scrolled-&gt;show();
  auto view = Gtk::manage(new Gtk::TextView());
  view-&gt;set_editable(false);
  view-&gt;set_cursor_visible(false);
  view-&gt;show();
  scrolled-&gt;add(*view);
  m_stack-&gt;add(*scrolled, basename, basename);

  auto buffer = view-&gt;get_buffer();
  try
  {
    char* contents = nullptr;
    gsize length = 0;
    
    file-&gt;load_contents(contents, length);
    buffer-&gt;set_text(contents, contents+length);
    g_free(contents);
  }
  catch (const Glib::Error&amp; ex)
  {
    std::cout &lt;&lt; "ExampleAppWindow::open_file_view(\"" &lt;&lt; file-&gt;get_parse_name()
      &lt;&lt; "\"):\n  " &lt;&lt; ex.what() &lt;&lt; std::endl;
    return;
  }

  auto tag = buffer-&gt;create_tag();
  m_settings-&gt;bind("font", tag-&gt;property_font());
  buffer-&gt;apply_tag(tag, buffer-&gt;begin(), buffer-&gt;end());

  m_search-&gt;set_sensitive(true);
}

void ExampleAppWindow::on_search_text_changed()
{
  const auto text = m_searchentry-&gt;get_text();
  if (text.empty())
    return;

  auto tab = dynamic_cast&lt;Gtk::ScrolledWindow*&gt;(m_stack-&gt;get_visible_child());
  if (!tab)
  {
    std::cout &lt;&lt; "ExampleAppWindow::on_search_text_changed(): No visible child." &lt;&lt; std::endl;
    return;
  }

  auto view = dynamic_cast&lt;Gtk::TextView*&gt;(tab-&gt;get_child());
  if (!view)
  {
    std::cout &lt;&lt; "ExampleAppWindow::on_search_text_changed(): No visible text view." &lt;&lt; std::endl;
    return;
  }

  // Very simple-minded search implementation.
  auto buffer = view-&gt;get_buffer();
  Gtk::TextIter match_start;
  Gtk::TextIter match_end;
  if (buffer-&gt;begin().forward_search(text, Gtk::TEXT_SEARCH_CASE_INSENSITIVE,
      match_start, match_end))
  {
    buffer-&gt;select_range(match_start, match_end);
    view-&gt;scroll_to(match_start);
  }
}

void ExampleAppWindow::on_visible_child_changed()
{
  m_searchbar-&gt;set_search_mode(false);
}

</programlisting>
<para lang="en">File: <filename>window.ui</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
&lt;?xml version="1.0" encoding="UTF-8"?&gt;
&lt;interface&gt;
  &lt;!-- interface-requires gtk+ 3.8 --&gt;
  &lt;object class="GtkApplicationWindow" id="app_window"&gt;
    &lt;property name="title" translatable="yes"&gt;Example Application&lt;/property&gt;
    &lt;property name="default-width"&gt;600&lt;/property&gt;
    &lt;property name="default-height"&gt;400&lt;/property&gt;
    &lt;child&gt;
      &lt;object class="GtkBox" id="content_box"&gt;
        &lt;property name="visible"&gt;True&lt;/property&gt;
        &lt;property name="orientation"&gt;vertical&lt;/property&gt;
        &lt;child&gt;
          &lt;object class="GtkHeaderBar" id="header"&gt;
            &lt;property name="visible"&gt;True&lt;/property&gt;
            &lt;child type="title"&gt;
              &lt;object class="GtkStackSwitcher" id="tabs"&gt;
                &lt;property name="visible"&gt;True&lt;/property&gt;
                &lt;property name="stack"&gt;stack&lt;/property&gt;
              &lt;/object&gt;
            &lt;/child&gt;
            &lt;child&gt;
              &lt;object class="GtkToggleButton" id="search"&gt;
                &lt;property name="visible"&gt;True&lt;/property&gt;
                &lt;property name="sensitive"&gt;False&lt;/property&gt;
                &lt;style&gt;
                  &lt;class name="image-button"/&gt;
                &lt;/style&gt;
                &lt;child&gt;
                  &lt;object class="GtkImage" id="search-icon"&gt;
                    &lt;property name="visible"&gt;True&lt;/property&gt;
                    &lt;property name="icon-name"&gt;edit-find-symbolic&lt;/property&gt;
                    &lt;property name="icon-size"&gt;1&lt;/property&gt;
                  &lt;/object&gt;
                &lt;/child&gt;
              &lt;/object&gt;
              &lt;packing&gt;
                &lt;property name="pack-type"&gt;end&lt;/property&gt;
              &lt;/packing&gt;
            &lt;/child&gt;
          &lt;/object&gt;
        &lt;/child&gt;
        &lt;child&gt;
          &lt;object class="GtkSearchBar" id="searchbar"&gt;
            &lt;property name="visible"&gt;True&lt;/property&gt;
            &lt;child&gt;
              &lt;object class="GtkSearchEntry" id="searchentry"&gt;
                &lt;property name="visible"&gt;True&lt;/property&gt;
              &lt;/object&gt;
            &lt;/child&gt;
          &lt;/object&gt;
        &lt;/child&gt;
        &lt;child&gt;
          &lt;object class="GtkStack" id="stack"&gt;
            &lt;property name="visible"&gt;True&lt;/property&gt;
            &lt;property name="transition-duration"&gt;500&lt;/property&gt;
          &lt;/object&gt;
        &lt;/child&gt;
      &lt;/object&gt;
    &lt;/child&gt;
  &lt;/object&gt;
&lt;/interface&gt;
</programlisting>
<!-- end inserted example code -->

</sect1>

<sect1 id="sec-buildapp-side-bar">
<title lang="en">Adding a side bar</title>

<para lang="en">
As another piece of functionality, we are adding a sidebar, which demonstrates
<classname>Gtk::MenuButton</classname>, <classname>Gtk::Revealer</classname> and
<classname>Gtk::ListBox</classname>. The new widgets are added in the <filename>window.ui</filename> file.
</para>

<para lang="en">
The code to populate the sidebar with buttons for the words found in each file is a
little too involved to go into here. But we'll look at the code to add the gears menu.
As expected by now, the gears menu is specified in a <classname>Gtk::Builder</classname>
ui file, <filename>gears_menu.ui</filename>
</para>

<para lang="en">
To connect the menu item to the new <literal>show-words</literal> setting, we use a
<classname>Gio::Action</classname> corresponding to the given <classname>Gio::Settings</classname>
key. In <classname>ExampleAppWindow</classname>'s constructor:
<programlisting lang="en">
<![CDATA[// Connect the menu to the MenuButton m_gears, and bind the show-words setting
// to the win.show-words action and the "Words" menu item.
// (The connection between action and menu item is specified in gears_menu.ui.)
auto menu_builder = Gtk::Builder::create_from_resource("/org/gtkmm/exampleapp/gears_menu.ui");
auto object = menu_builder->get_object("menu");
auto menu = Glib::RefPtr<Gio::MenuModel>::cast_dynamic(object);
m_gears->set_menu_model(menu);
add_action(m_settings->create_action("show-words"));]]>
</programlisting>
</para>

<para lang="en">
What our application looks like now:
</para>

<figure id="figure-buildapp-side-bar">
  <title lang="en">Adding a side bar</title>
  <screenshot>
    <graphic format="PNG" fileref="figures/buildapp_side_bar.png"/>
  </screenshot>
</figure>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/buildapp/step7?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>exampleappprefs.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "../step5/exampleappprefs.h"
// Equal to the corresponding file in step5
</programlisting>
<para lang="en">File: <filename>exampleappwindow.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLEAPPWINDOW_H_
#define GTKMM_EXAMPLEAPPWINDOW_H_

#include &lt;gtkmm.h&gt;

class ExampleAppWindow : public Gtk::ApplicationWindow
{
public:
  ExampleAppWindow(BaseObjectType* cobject,
    const Glib::RefPtr&lt;Gtk::Builder&gt;&amp; refBuilder);

  static ExampleAppWindow* create();

  void open_file_view(const Glib::RefPtr&lt;Gio::File&gt;&amp; file);

protected:
  // Signal handlers
  void on_search_text_changed();
  void on_visible_child_changed();
  void on_find_word(const Gtk::Button* button);
  void on_reveal_child_changed();

  void update_words();

  Glib::RefPtr&lt;Gtk::Builder&gt; m_refBuilder;
  Glib::RefPtr&lt;Gio::Settings&gt; m_settings;
  Gtk::Stack* m_stack;
  Gtk::ToggleButton* m_search;
  Gtk::SearchBar* m_searchbar;
  Gtk::SearchEntry* m_searchentry;
  Gtk::MenuButton* m_gears;
  Gtk::Revealer* m_sidebar;
  Gtk::ListBox* m_words;
  Glib::RefPtr&lt;Glib::Binding&gt; m_prop_binding;
};

#endif /* GTKMM_EXAMPLEAPPWINDOW_H */
</programlisting>
<para lang="en">File: <filename>exampleapplication.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "../step4/exampleapplication.h"
// Equal to the corresponding file in step4
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "../step5/main.cc"
// Equal to the corresponding file in step5
</programlisting>
<para lang="en">File: <filename>exampleappprefs.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "../step5/exampleappprefs.cc"
// Equal to the corresponding file in step5
</programlisting>
<para lang="en">File: <filename>exampleapplication.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "../step5/exampleapplication.cc"
// Equal to the corresponding file in step5
</programlisting>
<para lang="en">File: <filename>exampleappwindow.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "exampleappwindow.h"
#include &lt;iostream&gt;
#include &lt;stdexcept&gt;
#include &lt;set&gt;

ExampleAppWindow::ExampleAppWindow(BaseObjectType* cobject,
  const Glib::RefPtr&lt;Gtk::Builder&gt;&amp; refBuilder)
: Gtk::ApplicationWindow(cobject),
  m_refBuilder(refBuilder),
  m_settings(),
  m_stack(nullptr),
  m_search(nullptr),
  m_searchbar(nullptr),
  m_searchentry(nullptr),
  m_gears(nullptr),
  m_sidebar(nullptr),
  m_words(nullptr),
  m_prop_binding()
{
  // Get widgets from the Gtk::Builder file.
  m_refBuilder-&gt;get_widget("stack", m_stack);
  if (!m_stack)
    throw std::runtime_error("No \"stack\" object in window.ui");

  m_refBuilder-&gt;get_widget("search", m_search);
  if (!m_search)
    throw std::runtime_error("No \"search\" object in window.ui");

  m_refBuilder-&gt;get_widget("searchbar", m_searchbar);
  if (!m_searchbar)
    throw std::runtime_error("No \"searchbar\" object in window.ui");

  m_refBuilder-&gt;get_widget("searchentry", m_searchentry);
  if (!m_searchentry)
    throw std::runtime_error("No \"searchentry\" object in window.ui");

  m_refBuilder-&gt;get_widget("gears", m_gears);
  if (!m_gears)
    throw std::runtime_error("No \"gears\" object in window.ui");

  m_refBuilder-&gt;get_widget("sidebar", m_sidebar);
  if (!m_sidebar)
    throw std::runtime_error("No \"sidebar\" object in window.ui");

  m_refBuilder-&gt;get_widget("words", m_words);
  if (!m_words)
    throw std::runtime_error("No \"words\" object in window.ui");

  // Bind settings.
  m_settings = Gio::Settings::create("org.gtkmm.exampleapp");
  m_settings-&gt;bind("transition", m_stack-&gt;property_transition_type());
  m_settings-&gt;bind("show-words", m_sidebar-&gt;property_reveal_child());

  // Bind properties.
  m_prop_binding = Glib::Binding::bind_property(m_search-&gt;property_active(),
    m_searchbar-&gt;property_search_mode_enabled(), Glib::BINDING_BIDIRECTIONAL);

  // Connect signal handlers.
  m_searchentry-&gt;signal_search_changed().connect(
    sigc::mem_fun(*this, &amp;ExampleAppWindow::on_search_text_changed));
  m_stack-&gt;property_visible_child().signal_changed().connect(
    sigc::mem_fun(*this, &amp;ExampleAppWindow::on_visible_child_changed));
  m_sidebar-&gt;property_reveal_child().signal_changed().connect(
    sigc::mem_fun(*this, &amp;ExampleAppWindow::on_reveal_child_changed));

  // Connect the menu to the MenuButton m_gears, and bind the show-words setting
  // to the win.show-words action and the "Words" menu item.
  // (The connection between action and menu item is specified in gears_menu.ui.)
  auto menu_builder = Gtk::Builder::create_from_resource("/org/gtkmm/exampleapp/gears_menu.ui");
  auto object = menu_builder-&gt;get_object("menu");
  auto menu = Glib::RefPtr&lt;Gio::MenuModel&gt;::cast_dynamic(object);
  if (!menu)
    throw std::runtime_error("No \"menu\" object in gears_menu.ui");

  m_gears-&gt;set_menu_model(menu);
  add_action(m_settings-&gt;create_action("show-words"));
}

//static
ExampleAppWindow* ExampleAppWindow::create()
{
  // Load the Builder file and instantiate its widgets.
  auto refBuilder = Gtk::Builder::create_from_resource("/org/gtkmm/exampleapp/window.ui");

  ExampleAppWindow* window = nullptr;
  refBuilder-&gt;get_widget_derived("app_window", window);
  if (!window)
    throw std::runtime_error("No \"app_window\" object in window.ui");

  return window;
}

void ExampleAppWindow::open_file_view(const Glib::RefPtr&lt;Gio::File&gt;&amp; file)
{
  const auto basename = file-&gt;get_basename();

  auto scrolled = Gtk::manage(new Gtk::ScrolledWindow());
  scrolled-&gt;set_hexpand(true);
  scrolled-&gt;set_vexpand(true);
  scrolled-&gt;show();
  auto view = Gtk::manage(new Gtk::TextView());
  view-&gt;set_editable(false);
  view-&gt;set_cursor_visible(false);
  view-&gt;show();
  scrolled-&gt;add(*view);
  m_stack-&gt;add(*scrolled, basename, basename);

  auto buffer = view-&gt;get_buffer();
  try
  {
    char* contents = nullptr;
    gsize length = 0;
    
    file-&gt;load_contents(contents, length);
    buffer-&gt;set_text(contents, contents+length);
    g_free(contents);
  }
  catch (const Glib::Error&amp; ex)
  {
    std::cout &lt;&lt; "ExampleAppWindow::open_file_view(\"" &lt;&lt; file-&gt;get_parse_name()
      &lt;&lt; "\"):\n  " &lt;&lt; ex.what() &lt;&lt; std::endl;
    return;
  }

  auto tag = buffer-&gt;create_tag();
  m_settings-&gt;bind("font", tag-&gt;property_font());
  buffer-&gt;apply_tag(tag, buffer-&gt;begin(), buffer-&gt;end());

  m_search-&gt;set_sensitive(true);
  update_words();
}

void ExampleAppWindow::on_search_text_changed()
{
  const auto text = m_searchentry-&gt;get_text();
  if (text.empty())
    return;

  auto tab = dynamic_cast&lt;Gtk::ScrolledWindow*&gt;(m_stack-&gt;get_visible_child());
  if (!tab)
  {
    std::cout &lt;&lt; "ExampleAppWindow::on_search_text_changed(): No visible child." &lt;&lt; std::endl;
    return;
  }

  auto view = dynamic_cast&lt;Gtk::TextView*&gt;(tab-&gt;get_child());
  if (!view)
  {
    std::cout &lt;&lt; "ExampleAppWindow::on_search_text_changed(): No visible text view." &lt;&lt; std::endl;
    return;
  }

  // Very simple-minded search implementation.
  auto buffer = view-&gt;get_buffer();
  Gtk::TextIter match_start;
  Gtk::TextIter match_end;
  if (buffer-&gt;begin().forward_search(text, Gtk::TEXT_SEARCH_CASE_INSENSITIVE,
      match_start, match_end))
  {
    buffer-&gt;select_range(match_start, match_end);
    view-&gt;scroll_to(match_start);
  }
}

void ExampleAppWindow::on_visible_child_changed()
{
  m_searchbar-&gt;set_search_mode(false);
  update_words();
}

void ExampleAppWindow::on_find_word(const Gtk::Button* button)
{
  m_searchentry-&gt;set_text(button-&gt;get_label());
}

void ExampleAppWindow::on_reveal_child_changed()
{
  update_words();
}

void ExampleAppWindow::update_words()
{
  auto tab = dynamic_cast&lt;Gtk::ScrolledWindow*&gt;(m_stack-&gt;get_visible_child());
  if (!tab)
    return;

  auto view = dynamic_cast&lt;Gtk::TextView*&gt;(tab-&gt;get_child());
  if (!view)
  {
    std::cout &lt;&lt; "ExampleAppWindow::update_words(): No visible text view." &lt;&lt; std::endl;
    return;
  }
  auto buffer = view-&gt;get_buffer();

  // Find all words in the text buffer.
  std::set&lt;Glib::ustring&gt; words;
  auto start = buffer-&gt;begin();
  Gtk::TextIter end;
  while (start)
  {
    while (start &amp;&amp; !start.starts_word())
      ++start;

    if (!start)
      break;

    end = start;
    end.forward_word_end();
    if (start == end)
      break;

    auto word = buffer-&gt;get_text(start, end, false);
    words.insert(word.lowercase());
    start = end;
  }

  // Remove old children from the ListBox.
  auto old_children = m_words-&gt;get_children();
  for (auto child : old_children)
  {
    m_words-&gt;remove(*child);
    delete child;
  }

  // Add new child buttons, one per unique word.
  for (const auto&amp; word : words)
  {
    auto row = Gtk::manage(new Gtk::Button(word));
    row-&gt;signal_clicked().connect(sigc::bind(sigc::mem_fun(*this,
      &amp;ExampleAppWindow::on_find_word), row));
    row-&gt;show();
    m_words-&gt;add(*row);
  }
}
</programlisting>
<para lang="en">File: <filename>exampleapp.gresource.xml</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
&lt;?xml version="1.0" encoding="UTF-8"?&gt;
&lt;gresources&gt;
  &lt;gresource prefix="/org/gtkmm/exampleapp"&gt;
    &lt;file preprocess="xml-stripblanks"&gt;window.ui&lt;/file&gt;
    &lt;file preprocess="xml-stripblanks"&gt;app_menu.ui&lt;/file&gt;
    &lt;file preprocess="xml-stripblanks"&gt;gears_menu.ui&lt;/file&gt;
    &lt;file preprocess="xml-stripblanks"&gt;prefs.ui&lt;/file&gt;
  &lt;/gresource&gt;
&lt;/gresources&gt;
</programlisting>
<para lang="en">File: <filename>gears_menu.ui</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
&lt;?xml version="1.0"?&gt;
&lt;interface&gt;
  &lt;!-- interface-requires gtk+ 3.0 --&gt;
  &lt;menu id="menu"&gt;
    &lt;section&gt;
      &lt;item&gt;
        &lt;attribute name="label" translatable="yes"&gt;_Words&lt;/attribute&gt;
        &lt;attribute name="action"&gt;win.show-words&lt;/attribute&gt;
      &lt;/item&gt;
    &lt;/section&gt;
  &lt;/menu&gt;
&lt;/interface&gt;
</programlisting>
<para lang="en">File: <filename>window.ui</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
&lt;?xml version="1.0" encoding="UTF-8"?&gt;
&lt;interface&gt;
  &lt;!-- interface-requires gtk+ 3.8 --&gt;
  &lt;object class="GtkApplicationWindow" id="app_window"&gt;
    &lt;property name="title" translatable="yes"&gt;Example Application&lt;/property&gt;
    &lt;property name="default-width"&gt;600&lt;/property&gt;
    &lt;property name="default-height"&gt;400&lt;/property&gt;
    &lt;child&gt;
      &lt;object class="GtkBox" id="content_box"&gt;
        &lt;property name="visible"&gt;True&lt;/property&gt;
        &lt;property name="orientation"&gt;vertical&lt;/property&gt;
        &lt;child&gt;
          &lt;object class="GtkHeaderBar" id="header"&gt;
            &lt;property name="visible"&gt;True&lt;/property&gt;
            &lt;child type="title"&gt;
              &lt;object class="GtkStackSwitcher" id="tabs"&gt;
                &lt;property name="visible"&gt;True&lt;/property&gt;
                &lt;property name="stack"&gt;stack&lt;/property&gt;
              &lt;/object&gt;
            &lt;/child&gt;
            &lt;child&gt;
              &lt;object class="GtkToggleButton" id="search"&gt;
                &lt;property name="visible"&gt;True&lt;/property&gt;
                &lt;property name="sensitive"&gt;False&lt;/property&gt;
                &lt;style&gt;
                  &lt;class name="image-button"/&gt;
                &lt;/style&gt;
                &lt;child&gt;
                  &lt;object class="GtkImage" id="search-icon"&gt;
                    &lt;property name="visible"&gt;True&lt;/property&gt;
                    &lt;property name="icon-name"&gt;edit-find-symbolic&lt;/property&gt;
                    &lt;property name="icon-size"&gt;1&lt;/property&gt;
                  &lt;/object&gt;
                &lt;/child&gt;
              &lt;/object&gt;
              &lt;packing&gt;
                &lt;property name="pack-type"&gt;end&lt;/property&gt;
              &lt;/packing&gt;
            &lt;/child&gt;
            &lt;child&gt;
              &lt;object class="GtkMenuButton" id="gears"&gt;
                &lt;property name="visible"&gt;True&lt;/property&gt;
                &lt;property name="direction"&gt;none&lt;/property&gt;
                &lt;property name="use-popover"&gt;True&lt;/property&gt;
                &lt;style&gt;
                  &lt;class name="image-button"/&gt;
                &lt;/style&gt;
              &lt;/object&gt;
              &lt;packing&gt;
                &lt;property name="pack-type"&gt;end&lt;/property&gt;
              &lt;/packing&gt;
            &lt;/child&gt;
          &lt;/object&gt;
        &lt;/child&gt;
        &lt;child&gt;
          &lt;object class="GtkSearchBar" id="searchbar"&gt;
            &lt;property name="visible"&gt;True&lt;/property&gt;
            &lt;child&gt;
              &lt;object class="GtkSearchEntry" id="searchentry"&gt;
                &lt;property name="visible"&gt;True&lt;/property&gt;
              &lt;/object&gt;
            &lt;/child&gt;
          &lt;/object&gt;
        &lt;/child&gt;
        &lt;child&gt;
          &lt;object class="GtkBox" id="hbox"&gt;
            &lt;property name="visible"&gt;True&lt;/property&gt;
            &lt;child&gt;
              &lt;object class="GtkRevealer" id="sidebar"&gt;
                &lt;property name="visible"&gt;True&lt;/property&gt;
                &lt;property name="transition-type"&gt;slide-right&lt;/property&gt;
                &lt;child&gt;
                 &lt;object class="GtkScrolledWindow" id="sidebar-sw"&gt;
                   &lt;property name="visible"&gt;True&lt;/property&gt;
                   &lt;property name="hscrollbar-policy"&gt;never&lt;/property&gt;
                   &lt;property name="vscrollbar-policy"&gt;automatic&lt;/property&gt;
                   &lt;child&gt;
                     &lt;object class="GtkListBox" id="words"&gt;
                       &lt;property name="visible"&gt;True&lt;/property&gt;
                       &lt;property name="selection-mode"&gt;none&lt;/property&gt;
                     &lt;/object&gt;
                   &lt;/child&gt;
                 &lt;/object&gt;
                &lt;/child&gt;
              &lt;/object&gt;
            &lt;/child&gt;
            &lt;child&gt;
              &lt;object class="GtkStack" id="stack"&gt;
                &lt;property name="visible"&gt;True&lt;/property&gt;
                &lt;property name="transition-duration"&gt;500&lt;/property&gt;
              &lt;/object&gt;
            &lt;/child&gt;
          &lt;/object&gt;
        &lt;/child&gt;
      &lt;/object&gt;
    &lt;/child&gt;
  &lt;/object&gt;
&lt;/interface&gt;
</programlisting>
<para lang="en">File: <filename>org.gtkmm.exampleapp.gschema.xml</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
&lt;?xml version="1.0" encoding="UTF-8"?&gt;
&lt;schemalist&gt;
  &lt;schema path="/org/gtkmm/exampleapp/" id="org.gtkmm.exampleapp"&gt;
    &lt;key name="font" type="s"&gt;
      &lt;default&gt;'Monospace 12'&lt;/default&gt;
      &lt;summary&gt;Font&lt;/summary&gt;
      &lt;description&gt;The font to be used for content.&lt;/description&gt;
    &lt;/key&gt;
    &lt;key name="transition" type="s"&gt;
      &lt;choices&gt;
        &lt;choice value='none'/&gt;
        &lt;choice value='crossfade'/&gt;
        &lt;choice value='slide-left-right'/&gt;
      &lt;/choices&gt;
      &lt;default&gt;'none'&lt;/default&gt;
      &lt;summary&gt;Transition&lt;/summary&gt;
      &lt;description&gt;The transition to use when switching tabs.&lt;/description&gt;
    &lt;/key&gt;
    &lt;key name="show-words" type="b"&gt;
      &lt;default&gt;false&lt;/default&gt;
      &lt;summary&gt;Show words&lt;/summary&gt;
      &lt;description&gt;Whether to show a word list in the sidebar.&lt;/description&gt;
    &lt;/key&gt;
  &lt;/schema&gt;
&lt;/schemalist&gt;
</programlisting>
<!-- end inserted example code -->


</sect1>

<sect1 id="sec-buildapp-properties">
<title lang="en">Properties</title>

<para lang="en">
Widgets and other objects have many useful properties. Here we show some ways to use
them in new and flexible ways, by wrapping them in actions with <classname>Gio::PropertyAction</classname>
or by binding them with <classname>Glib::Binding</classname>.
(At the time of writing (october 2016) <classname>Gio::PropertyAction</classname>
does not exist. We have to call a <application>glib</application> function directly.)
</para>

<para lang="en">
To set this up, we add two labels to the header bar in our <filename>window.ui</filename> file,
named <literal>lines_label</literal> and <literal>lines</literal>, and get pointers to them
in the application window's constructor, as we've seen a couple of times by now.
We add a new "Lines" menu item to the gears menu, which triggers the
<literal>show-lines</literal> action.
</para>

<para lang="en">
To make this menu item do something, we create a property action for the <literal>visible</literal>
property of the <literal>lines</literal> label, and add it to the actions of the window.
The effect of this is that the visibility of the label gets toggled every time the action
is activated.
Since we want both labels to appear and disappear together, we bind the <literal>visible</literal>
property of the <literal>lines_label</literal> widget to the same property of the
<literal>lines</literal> widget.
In <classname>ExampleAppWindow</classname>'s constructor:
<programlisting lang="en">add_action(Glib::wrap((GAction*)
  g_property_action_new("show-lines", m_lines-&gt;gobj(), "visible")));
m_binding_lines_visible = Glib::Binding::bind_property(m_lines-&gt;property_visible(),
  m_lines_label-&gt;property_visible());<![CDATA[
]]>
</programlisting>
</para>

<para lang="en">
We also need a function that counts the lines of the currently active tab, and updates
the <literal>lines</literal> label. See the full source if you are interested in the details.
</para>

<para lang="en">
This brings our example application to this appearance:
</para>

<figure id="figure-buildapp-properties">
  <title lang="en">Properties</title>
  <screenshot>
    <graphic format="PNG" fileref="figures/buildapp_properties.png"/>
  </screenshot>
</figure>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/buildapp/step8?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>exampleappprefs.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "../step5/exampleappprefs.h"
// Equal to the corresponding file in step5
</programlisting>
<para lang="en">File: <filename>exampleappwindow.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLEAPPWINDOW_H_
#define GTKMM_EXAMPLEAPPWINDOW_H_

#include &lt;gtkmm.h&gt;

class ExampleAppWindow : public Gtk::ApplicationWindow
{
public:
  ExampleAppWindow(BaseObjectType* cobject,
    const Glib::RefPtr&lt;Gtk::Builder&gt;&amp; refBuilder);

  static ExampleAppWindow* create();

  void open_file_view(const Glib::RefPtr&lt;Gio::File&gt;&amp; file);

protected:
  // Signal handlers
  void on_search_text_changed();
  void on_visible_child_changed();
  void on_find_word(const Gtk::Button* button);
  void on_reveal_child_changed();

  void update_words();
  void update_lines();

  Glib::RefPtr&lt;Gtk::Builder&gt; m_refBuilder;
  Glib::RefPtr&lt;Gio::Settings&gt; m_settings;
  Gtk::Stack* m_stack;
  Gtk::ToggleButton* m_search;
  Gtk::SearchBar* m_searchbar;
  Gtk::SearchEntry* m_searchentry;
  Gtk::MenuButton* m_gears;
  Gtk::Revealer* m_sidebar;
  Gtk::ListBox* m_words;
  Gtk::Label* m_lines;
  Gtk::Label* m_lines_label;
  Glib::RefPtr&lt;Glib::Binding&gt; m_binding_search_enabled;
  Glib::RefPtr&lt;Glib::Binding&gt; m_binding_lines_visible;
};

#endif /* GTKMM_EXAMPLEAPPWINDOW_H */
</programlisting>
<para lang="en">File: <filename>exampleapplication.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "../step4/exampleapplication.h"
// Equal to the corresponding file in step4
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "../step5/main.cc"
// Equal to the corresponding file in step5
</programlisting>
<para lang="en">File: <filename>exampleappprefs.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "../step5/exampleappprefs.cc"
// Equal to the corresponding file in step5
</programlisting>
<para lang="en">File: <filename>exampleapplication.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "../step5/exampleapplication.cc"
// Equal to the corresponding file in step5
</programlisting>
<para lang="en">File: <filename>exampleappwindow.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "exampleappwindow.h"
#include &lt;iostream&gt;
#include &lt;stdexcept&gt;
#include &lt;set&gt;

ExampleAppWindow::ExampleAppWindow(BaseObjectType* cobject,
  const Glib::RefPtr&lt;Gtk::Builder&gt;&amp; refBuilder)
: Gtk::ApplicationWindow(cobject),
  m_refBuilder(refBuilder),
  m_settings(),
  m_stack(nullptr),
  m_search(nullptr),
  m_searchbar(nullptr),
  m_searchentry(nullptr),
  m_gears(nullptr),
  m_sidebar(nullptr),
  m_words(nullptr),
  m_lines(nullptr),
  m_lines_label(nullptr),
  m_binding_search_enabled(),
  m_binding_lines_visible()
{
  // Get widgets from the Gtk::Builder file.
  m_refBuilder-&gt;get_widget("stack", m_stack);
  if (!m_stack)
    throw std::runtime_error("No \"stack\" object in window.ui");

  m_refBuilder-&gt;get_widget("search", m_search);
  if (!m_search)
    throw std::runtime_error("No \"search\" object in window.ui");

  m_refBuilder-&gt;get_widget("searchbar", m_searchbar);
  if (!m_searchbar)
    throw std::runtime_error("No \"searchbar\" object in window.ui");

  m_refBuilder-&gt;get_widget("searchentry", m_searchentry);
  if (!m_searchentry)
    throw std::runtime_error("No \"searchentry\" object in window.ui");

  m_refBuilder-&gt;get_widget("gears", m_gears);
  if (!m_gears)
    throw std::runtime_error("No \"gears\" object in window.ui");

  m_refBuilder-&gt;get_widget("sidebar", m_sidebar);
  if (!m_sidebar)
    throw std::runtime_error("No \"sidebar\" object in window.ui");

  m_refBuilder-&gt;get_widget("words", m_words);
  if (!m_words)
    throw std::runtime_error("No \"words\" object in window.ui");

  m_refBuilder-&gt;get_widget("lines", m_lines);
  if (!m_lines)
    throw std::runtime_error("No \"lines\" object in window.ui");

  m_refBuilder-&gt;get_widget("lines_label", m_lines_label);
  if (!m_lines_label)
    throw std::runtime_error("No \"lines_label\" object in window.ui");

  // Bind settings.
  m_settings = Gio::Settings::create("org.gtkmm.exampleapp");
  m_settings-&gt;bind("transition", m_stack-&gt;property_transition_type());
  m_settings-&gt;bind("show-words", m_sidebar-&gt;property_reveal_child());

  // Bind properties of the search button to the search bar.
  m_binding_search_enabled = Glib::Binding::bind_property(m_search-&gt;property_active(),
    m_searchbar-&gt;property_search_mode_enabled(), Glib::BINDING_BIDIRECTIONAL);

  // Connect signal handlers.
  m_searchentry-&gt;signal_search_changed().connect(
    sigc::mem_fun(*this, &amp;ExampleAppWindow::on_search_text_changed));
  m_stack-&gt;property_visible_child().signal_changed().connect(
    sigc::mem_fun(*this, &amp;ExampleAppWindow::on_visible_child_changed));
  m_sidebar-&gt;property_reveal_child().signal_changed().connect(
    sigc::mem_fun(*this, &amp;ExampleAppWindow::on_reveal_child_changed));

  // Connect the menu to the MenuButton m_gears, and bind the show-words setting
  // to the win.show-words action and the "Words" menu item.
  // (The connection between action and menu item is specified in gears_menu.ui.)
  auto menu_builder = Gtk::Builder::create_from_resource("/org/gtkmm/exampleapp/gears_menu.ui");
  auto object = menu_builder-&gt;get_object("menu");
  auto menu = Glib::RefPtr&lt;Gio::MenuModel&gt;::cast_dynamic(object);
  if (!menu)
    throw std::runtime_error("No \"menu\" object in gears_menu.ui");

  m_gears-&gt;set_menu_model(menu);
  add_action(m_settings-&gt;create_action("show-words"));

  // Bind the "visible" property of m_lines to the win.show-lines action, to
  // the "Lines" menu item and to the "visible" property of m_lines_label.
  // The GPropertyAction class is not wrapped in a glibmm class at the time of
  // writing (october 2016). We have to call a glib function directly.
  add_action(Glib::wrap((GAction*)
    g_property_action_new("show-lines", m_lines-&gt;gobj(), "visible")));
  m_binding_lines_visible = Glib::Binding::bind_property(m_lines-&gt;property_visible(),
    m_lines_label-&gt;property_visible());
}

//static
ExampleAppWindow* ExampleAppWindow::create()
{
  // Load the Builder file and instantiate its widgets.
  auto refBuilder = Gtk::Builder::create_from_resource("/org/gtkmm/exampleapp/window.ui");

  ExampleAppWindow* window = nullptr;
  refBuilder-&gt;get_widget_derived("app_window", window);
  if (!window)
    throw std::runtime_error("No \"app_window\" object in window.ui");

  return window;
}

void ExampleAppWindow::open_file_view(const Glib::RefPtr&lt;Gio::File&gt;&amp; file)
{
  const auto basename = file-&gt;get_basename();

  auto scrolled = Gtk::manage(new Gtk::ScrolledWindow());
  scrolled-&gt;set_hexpand(true);
  scrolled-&gt;set_vexpand(true);
  scrolled-&gt;show();
  auto view = Gtk::manage(new Gtk::TextView());
  view-&gt;set_editable(false);
  view-&gt;set_cursor_visible(false);
  view-&gt;show();
  scrolled-&gt;add(*view);
  m_stack-&gt;add(*scrolled, basename, basename);

  auto buffer = view-&gt;get_buffer();
  try
  {
    char* contents = nullptr;
    gsize length = 0;
    
    file-&gt;load_contents(contents, length);
    buffer-&gt;set_text(contents, contents+length);
    g_free(contents);
  }
  catch (const Glib::Error&amp; ex)
  {
    std::cout &lt;&lt; "ExampleAppWindow::open_file_view(\"" &lt;&lt; file-&gt;get_parse_name()
      &lt;&lt; "\"):\n  " &lt;&lt; ex.what() &lt;&lt; std::endl;
    return;
  }

  auto tag = buffer-&gt;create_tag();
  m_settings-&gt;bind("font", tag-&gt;property_font());
  buffer-&gt;apply_tag(tag, buffer-&gt;begin(), buffer-&gt;end());

  m_search-&gt;set_sensitive(true);
  update_words();
  update_lines();
}

void ExampleAppWindow::on_search_text_changed()
{
  const auto text = m_searchentry-&gt;get_text();
  if (text.empty())
    return;

  auto tab = dynamic_cast&lt;Gtk::ScrolledWindow*&gt;(m_stack-&gt;get_visible_child());
  if (!tab)
  {
    std::cout &lt;&lt; "ExampleAppWindow::on_search_text_changed(): No visible child." &lt;&lt; std::endl;
    return;
  }

  auto view = dynamic_cast&lt;Gtk::TextView*&gt;(tab-&gt;get_child());
  if (!view)
  {
    std::cout &lt;&lt; "ExampleAppWindow::on_search_text_changed(): No visible text view." &lt;&lt; std::endl;
    return;
  }

  // Very simple-minded search implementation.
  auto buffer = view-&gt;get_buffer();
  Gtk::TextIter match_start;
  Gtk::TextIter match_end;
  if (buffer-&gt;begin().forward_search(text, Gtk::TEXT_SEARCH_CASE_INSENSITIVE,
      match_start, match_end))
  {
    buffer-&gt;select_range(match_start, match_end);
    view-&gt;scroll_to(match_start);
  }
}

void ExampleAppWindow::on_visible_child_changed()
{
  m_searchbar-&gt;set_search_mode(false);
  update_words();
  update_lines();  
}

void ExampleAppWindow::on_find_word(const Gtk::Button* button)
{
  m_searchentry-&gt;set_text(button-&gt;get_label());
}

void ExampleAppWindow::on_reveal_child_changed()
{
  update_words();
}

void ExampleAppWindow::update_words()
{
  auto tab = dynamic_cast&lt;Gtk::ScrolledWindow*&gt;(m_stack-&gt;get_visible_child());
  if (!tab)
    return;

  auto view = dynamic_cast&lt;Gtk::TextView*&gt;(tab-&gt;get_child());
  if (!view)
  {
    std::cout &lt;&lt; "ExampleAppWindow::update_words(): No visible text view." &lt;&lt; std::endl;
    return;
  }
  auto buffer = view-&gt;get_buffer();

  // Find all words in the text buffer.
  std::set&lt;Glib::ustring&gt; words;
  auto start = buffer-&gt;begin();
  Gtk::TextIter end;
  while (start)
  {
    while (start &amp;&amp; !start.starts_word())
      ++start;

    if (!start)
      break;

    end = start;
    end.forward_word_end();
    if (start == end)
      break;

    auto word = buffer-&gt;get_text(start, end, false);
    words.insert(word.lowercase());
    start = end;
  }

  // Remove old children from the ListBox.
  auto old_children = m_words-&gt;get_children();
  for (auto child : old_children)
  {
    m_words-&gt;remove(*child);
    delete child;
  }

  // Add new child buttons, one per unique word.
  for (const auto&amp; word : words)
  {
    auto row = Gtk::manage(new Gtk::Button(word));
    row-&gt;signal_clicked().connect(sigc::bind(sigc::mem_fun(*this,
      &amp;ExampleAppWindow::on_find_word), row));
    row-&gt;show();
    m_words-&gt;add(*row);
  }
}

void ExampleAppWindow::update_lines()
{
  auto tab = dynamic_cast&lt;Gtk::ScrolledWindow*&gt;(m_stack-&gt;get_visible_child());
  if (!tab)
    return;

  auto view = dynamic_cast&lt;Gtk::TextView*&gt;(tab-&gt;get_child());
  if (!view)
  {
    std::cout &lt;&lt; "ExampleAppWindow::update_lines(): No visible text view." &lt;&lt; std::endl;
    return;
  }
  auto buffer = view-&gt;get_buffer();

  int count = 0;
  auto iter = buffer-&gt;begin();
  while (iter)
  {
    ++count;
    if (!iter.forward_line())
      break;
  }
  m_lines-&gt;set_text(Glib::ustring::format(count));
}
</programlisting>
<para lang="en">File: <filename>gears_menu.ui</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
&lt;?xml version="1.0"?&gt;
&lt;interface&gt;
  &lt;!-- interface-requires gtk+ 3.0 --&gt;
  &lt;menu id="menu"&gt;
    &lt;section&gt;
      &lt;item&gt;
        &lt;attribute name="label" translatable="yes"&gt;_Words&lt;/attribute&gt;
        &lt;attribute name="action"&gt;win.show-words&lt;/attribute&gt;
      &lt;/item&gt;
      &lt;item&gt;
        &lt;attribute name="label" translatable="yes"&gt;_Lines&lt;/attribute&gt;
        &lt;attribute name="action"&gt;win.show-lines&lt;/attribute&gt;
      &lt;/item&gt;
    &lt;/section&gt;
  &lt;/menu&gt;
&lt;/interface&gt;
</programlisting>
<para lang="en">File: <filename>window.ui</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
&lt;?xml version="1.0" encoding="UTF-8"?&gt;
&lt;interface&gt;
  &lt;!-- interface-requires gtk+ 3.8 --&gt;
  &lt;object class="GtkApplicationWindow" id="app_window"&gt;
    &lt;property name="title" translatable="yes"&gt;Example Application&lt;/property&gt;
    &lt;property name="default-width"&gt;600&lt;/property&gt;
    &lt;property name="default-height"&gt;400&lt;/property&gt;
    &lt;child&gt;
      &lt;object class="GtkBox" id="content_box"&gt;
        &lt;property name="visible"&gt;True&lt;/property&gt;
        &lt;property name="orientation"&gt;vertical&lt;/property&gt;
        &lt;child&gt;
          &lt;object class="GtkHeaderBar" id="header"&gt;
            &lt;property name="visible"&gt;True&lt;/property&gt;
            &lt;child&gt;
              &lt;object class="GtkLabel" id="lines_label"&gt;
                &lt;property name="visible"&gt;False&lt;/property&gt;
                &lt;property name="label" translatable="yes"&gt;Lines:&lt;/property&gt;
              &lt;/object&gt;
              &lt;packing&gt;
                &lt;property name="pack-type"&gt;start&lt;/property&gt;
              &lt;/packing&gt;
            &lt;/child&gt;
            &lt;child&gt;
              &lt;object class="GtkLabel" id="lines"&gt;
                &lt;property name="visible"&gt;False&lt;/property&gt;
              &lt;/object&gt;
              &lt;packing&gt;
                &lt;property name="pack-type"&gt;start&lt;/property&gt;
              &lt;/packing&gt;
            &lt;/child&gt;
            &lt;child type="title"&gt;
              &lt;object class="GtkStackSwitcher" id="tabs"&gt;
                &lt;property name="visible"&gt;True&lt;/property&gt;
                &lt;property name="stack"&gt;stack&lt;/property&gt;
              &lt;/object&gt;
            &lt;/child&gt;
            &lt;child&gt;
              &lt;object class="GtkToggleButton" id="search"&gt;
                &lt;property name="visible"&gt;True&lt;/property&gt;
                &lt;property name="sensitive"&gt;False&lt;/property&gt;
                &lt;style&gt;
                  &lt;class name="image-button"/&gt;
                &lt;/style&gt;
                &lt;child&gt;
                  &lt;object class="GtkImage" id="search-icon"&gt;
                    &lt;property name="visible"&gt;True&lt;/property&gt;
                    &lt;property name="icon-name"&gt;edit-find-symbolic&lt;/property&gt;
                    &lt;property name="icon-size"&gt;1&lt;/property&gt;
                  &lt;/object&gt;
                &lt;/child&gt;
              &lt;/object&gt;
              &lt;packing&gt;
                &lt;property name="pack-type"&gt;end&lt;/property&gt;
              &lt;/packing&gt;
            &lt;/child&gt;
            &lt;child&gt;
              &lt;object class="GtkMenuButton" id="gears"&gt;
                &lt;property name="visible"&gt;True&lt;/property&gt;
                &lt;property name="direction"&gt;none&lt;/property&gt;
                &lt;property name="use-popover"&gt;True&lt;/property&gt;
                &lt;style&gt;
                  &lt;class name="image-button"/&gt;
                &lt;/style&gt;
              &lt;/object&gt;
              &lt;packing&gt;
                &lt;property name="pack-type"&gt;end&lt;/property&gt;
              &lt;/packing&gt;
            &lt;/child&gt;
          &lt;/object&gt;
        &lt;/child&gt;
        &lt;child&gt;
          &lt;object class="GtkSearchBar" id="searchbar"&gt;
            &lt;property name="visible"&gt;True&lt;/property&gt;
            &lt;child&gt;
              &lt;object class="GtkSearchEntry" id="searchentry"&gt;
                &lt;property name="visible"&gt;True&lt;/property&gt;
              &lt;/object&gt;
            &lt;/child&gt;
          &lt;/object&gt;
        &lt;/child&gt;
        &lt;child&gt;
          &lt;object class="GtkBox" id="hbox"&gt;
            &lt;property name="visible"&gt;True&lt;/property&gt;
            &lt;child&gt;
              &lt;object class="GtkRevealer" id="sidebar"&gt;
                &lt;property name="visible"&gt;True&lt;/property&gt;
                &lt;property name="transition-type"&gt;slide-right&lt;/property&gt;
                &lt;child&gt;
                 &lt;object class="GtkScrolledWindow" id="sidebar-sw"&gt;
                   &lt;property name="visible"&gt;True&lt;/property&gt;
                   &lt;property name="hscrollbar-policy"&gt;never&lt;/property&gt;
                   &lt;property name="vscrollbar-policy"&gt;automatic&lt;/property&gt;
                   &lt;child&gt;
                     &lt;object class="GtkListBox" id="words"&gt;
                       &lt;property name="visible"&gt;True&lt;/property&gt;
                       &lt;property name="selection-mode"&gt;none&lt;/property&gt;
                     &lt;/object&gt;
                   &lt;/child&gt;
                 &lt;/object&gt;
                &lt;/child&gt;
              &lt;/object&gt;
            &lt;/child&gt;
            &lt;child&gt;
              &lt;object class="GtkStack" id="stack"&gt;
                &lt;property name="visible"&gt;True&lt;/property&gt;
                &lt;property name="transition-duration"&gt;500&lt;/property&gt;
              &lt;/object&gt;
            &lt;/child&gt;
          &lt;/object&gt;
        &lt;/child&gt;
      &lt;/object&gt;
    &lt;/child&gt;
  &lt;/object&gt;
&lt;/interface&gt;
</programlisting>
<!-- end inserted example code -->

</sect1>

<sect1 id="sec-buildapp-header-bar">
<title lang="en">Header bar</title>

<para lang="en">
Our application already uses a <classname>Gtk::HeaderBar</classname>, but so far it still
gets a 'normal' window titlebar on top of that. This is a bit redundant, and we will now
tell <application>gtkmm</application> to use the header bar as replacement for the titlebar. To do so, we move
it around to be a direct child of the window, and set its type to be <literal>titlebar</literal>.
This is done in the <filename>window.ui</filename> file.
</para>

<para lang="en">
A small extra bonus of using a header bar is that we get a fallback application menu
button for free. We include an icon in the resource file, and set up this icon as the
window icon. Then it is displayed in the menu button.
</para>

<para lang="en">
Here is how the application now looks, if the fallback menu is used:
</para>

<figure id="figure-buildapp-header-bar">
  <title lang="en">Header bar</title>
  <screenshot>
    <graphic format="PNG" fileref="figures/buildapp_header_bar.png"/>
  </screenshot>
</figure>

<para lang="en">
The <filename>window.ui</filename> file sets a header bar title, but this title is not shown.
That's because the stack switcher is a child of type <literal>title</literal>. The stack
switcher becomes a custom title that hides the title label, as if it had been set with
<methodname>Gtk::HeaderBar::set_custom_title()</methodname>.
</para>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/buildapp/step9?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>exampleappprefs.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "../step5/exampleappprefs.h"
// Equal to the corresponding file in step5
</programlisting>
<para lang="en">File: <filename>exampleappwindow.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "../step8/exampleappwindow.h"
// Equal to the corresponding file in step8
</programlisting>
<para lang="en">File: <filename>exampleapplication.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "../step4/exampleapplication.h"
// Equal to the corresponding file in step4
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "../step5/main.cc"
// Equal to the corresponding file in step5
</programlisting>
<para lang="en">File: <filename>exampleappprefs.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "../step5/exampleappprefs.cc"
// Equal to the corresponding file in step5
</programlisting>
<para lang="en">File: <filename>exampleapplication.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "../step5/exampleapplication.cc"
// Equal to the corresponding file in step5
</programlisting>
<para lang="en">File: <filename>exampleappwindow.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "exampleappwindow.h"
#include &lt;iostream&gt;
#include &lt;stdexcept&gt;
#include &lt;set&gt;

ExampleAppWindow::ExampleAppWindow(BaseObjectType* cobject,
  const Glib::RefPtr&lt;Gtk::Builder&gt;&amp; refBuilder)
: Gtk::ApplicationWindow(cobject),
  m_refBuilder(refBuilder),
  m_settings(),
  m_stack(nullptr),
  m_search(nullptr),
  m_searchbar(nullptr),
  m_searchentry(nullptr),
  m_gears(nullptr),
  m_sidebar(nullptr),
  m_words(nullptr),
  m_lines(nullptr),
  m_lines_label(nullptr),
  m_binding_search_enabled(),
  m_binding_lines_visible()
{
  // Get widgets from the Gtk::Builder file.
  m_refBuilder-&gt;get_widget("stack", m_stack);
  if (!m_stack)
    throw std::runtime_error("No \"stack\" object in window.ui");

  m_refBuilder-&gt;get_widget("search", m_search);
  if (!m_search)
    throw std::runtime_error("No \"search\" object in window.ui");

  m_refBuilder-&gt;get_widget("searchbar", m_searchbar);
  if (!m_searchbar)
    throw std::runtime_error("No \"searchbar\" object in window.ui");

  m_refBuilder-&gt;get_widget("searchentry", m_searchentry);
  if (!m_searchentry)
    throw std::runtime_error("No \"searchentry\" object in window.ui");

  m_refBuilder-&gt;get_widget("gears", m_gears);
  if (!m_gears)
    throw std::runtime_error("No \"gears\" object in window.ui");

  m_refBuilder-&gt;get_widget("sidebar", m_sidebar);
  if (!m_sidebar)
    throw std::runtime_error("No \"sidebar\" object in window.ui");

  m_refBuilder-&gt;get_widget("words", m_words);
  if (!m_words)
    throw std::runtime_error("No \"words\" object in window.ui");

  m_refBuilder-&gt;get_widget("lines", m_lines);
  if (!m_lines)
    throw std::runtime_error("No \"lines\" object in window.ui");

  m_refBuilder-&gt;get_widget("lines_label", m_lines_label);
  if (!m_lines_label)
    throw std::runtime_error("No \"lines_label\" object in window.ui");

  // Bind settings.
  m_settings = Gio::Settings::create("org.gtkmm.exampleapp");
  m_settings-&gt;bind("transition", m_stack-&gt;property_transition_type());
  m_settings-&gt;bind("show-words", m_sidebar-&gt;property_reveal_child());

  // Bind properties of the search button to the search bar.
  m_binding_search_enabled = Glib::Binding::bind_property(m_search-&gt;property_active(),
    m_searchbar-&gt;property_search_mode_enabled(), Glib::BINDING_BIDIRECTIONAL);

  // Connect signal handlers.
  m_searchentry-&gt;signal_search_changed().connect(
    sigc::mem_fun(*this, &amp;ExampleAppWindow::on_search_text_changed));
  m_stack-&gt;property_visible_child().signal_changed().connect(
    sigc::mem_fun(*this, &amp;ExampleAppWindow::on_visible_child_changed));
  m_sidebar-&gt;property_reveal_child().signal_changed().connect(
    sigc::mem_fun(*this, &amp;ExampleAppWindow::on_reveal_child_changed));

  // Connect the menu to the MenuButton m_gears, and bind the show-words setting
  // to the win.show-words action and the "Words" menu item.
  // (The connection between action and menu item is specified in gears_menu.ui.)
  auto menu_builder = Gtk::Builder::create_from_resource("/org/gtkmm/exampleapp/gears_menu.ui");
  auto object = menu_builder-&gt;get_object("menu");
  auto menu = Glib::RefPtr&lt;Gio::MenuModel&gt;::cast_dynamic(object);
  if (!menu)
    throw std::runtime_error("No \"menu\" object in gears_menu.ui");

  m_gears-&gt;set_menu_model(menu);
  add_action(m_settings-&gt;create_action("show-words"));

  // Bind the "visible" property of m_lines to the win.show-lines action, to
  // the "Lines" menu item and to the "visible" property of m_lines_label.
  // The GPropertyAction class is not wrapped in a glibmm class at the time of
  // writing (october 2016). We have to call a glib function directly.
  add_action(Glib::wrap((GAction*)
    g_property_action_new("show-lines", m_lines-&gt;gobj(), "visible")));
  m_binding_lines_visible = Glib::Binding::bind_property(m_lines-&gt;property_visible(),
    m_lines_label-&gt;property_visible());

  // Display the application menu in the application, not in the desktop environment.
  auto gtk_settings = Gtk::Settings::get_default();
  if (gtk_settings)
    gtk_settings-&gt;property_gtk_shell_shows_app_menu() = false;
  set_show_menubar(true);

  // Set the window icon.
  set_icon(Gdk::Pixbuf::create_from_resource("/org/gtkmm/exampleapp/exampleapp.png"));
}

//static
ExampleAppWindow* ExampleAppWindow::create()
{
  // Load the Builder file and instantiate its widgets.
  auto refBuilder = Gtk::Builder::create_from_resource("/org/gtkmm/exampleapp/window.ui");

  ExampleAppWindow* window = nullptr;
  refBuilder-&gt;get_widget_derived("app_window", window);
  if (!window)
    throw std::runtime_error("No \"app_window\" object in window.ui");

  return window;
}

void ExampleAppWindow::open_file_view(const Glib::RefPtr&lt;Gio::File&gt;&amp; file)
{
  const auto basename = file-&gt;get_basename();

  auto scrolled = Gtk::manage(new Gtk::ScrolledWindow());
  scrolled-&gt;set_hexpand(true);
  scrolled-&gt;set_vexpand(true);
  scrolled-&gt;show();
  auto view = Gtk::manage(new Gtk::TextView());
  view-&gt;set_editable(false);
  view-&gt;set_cursor_visible(false);
  view-&gt;show();
  scrolled-&gt;add(*view);
  m_stack-&gt;add(*scrolled, basename, basename);

  auto buffer = view-&gt;get_buffer();
  try
  {
    char* contents = nullptr;
    gsize length = 0;
    
    file-&gt;load_contents(contents, length);
    buffer-&gt;set_text(contents, contents+length);
    g_free(contents);
  }
  catch (const Glib::Error&amp; ex)
  {
    std::cout &lt;&lt; "ExampleAppWindow::open_file_view(\"" &lt;&lt; file-&gt;get_parse_name()
      &lt;&lt; "\"):\n  " &lt;&lt; ex.what() &lt;&lt; std::endl;
    return;
  }

  auto tag = buffer-&gt;create_tag();
  m_settings-&gt;bind("font", tag-&gt;property_font());
  buffer-&gt;apply_tag(tag, buffer-&gt;begin(), buffer-&gt;end());

  m_search-&gt;set_sensitive(true);
  update_words();
  update_lines();
}

void ExampleAppWindow::on_search_text_changed()
{
  const auto text = m_searchentry-&gt;get_text();
  if (text.empty())
    return;

  auto tab = dynamic_cast&lt;Gtk::ScrolledWindow*&gt;(m_stack-&gt;get_visible_child());
  if (!tab)
  {
    std::cout &lt;&lt; "ExampleAppWindow::on_search_text_changed(): No visible child." &lt;&lt; std::endl;
    return;
  }

  auto view = dynamic_cast&lt;Gtk::TextView*&gt;(tab-&gt;get_child());
  if (!view)
  {
    std::cout &lt;&lt; "ExampleAppWindow::on_search_text_changed(): No visible text view." &lt;&lt; std::endl;
    return;
  }

  // Very simple-minded search implementation.
  auto buffer = view-&gt;get_buffer();
  Gtk::TextIter match_start;
  Gtk::TextIter match_end;
  if (buffer-&gt;begin().forward_search(text, Gtk::TEXT_SEARCH_CASE_INSENSITIVE,
      match_start, match_end))
  {
    buffer-&gt;select_range(match_start, match_end);
    view-&gt;scroll_to(match_start);
  }
}

void ExampleAppWindow::on_visible_child_changed()
{
  m_searchbar-&gt;set_search_mode(false);
  update_words();
  update_lines();  
}

void ExampleAppWindow::on_find_word(const Gtk::Button* button)
{
  m_searchentry-&gt;set_text(button-&gt;get_label());
}

void ExampleAppWindow::on_reveal_child_changed()
{
  update_words();
}

void ExampleAppWindow::update_words()
{
  auto tab = dynamic_cast&lt;Gtk::ScrolledWindow*&gt;(m_stack-&gt;get_visible_child());
  if (!tab)
    return;

  auto view = dynamic_cast&lt;Gtk::TextView*&gt;(tab-&gt;get_child());
  if (!view)
  {
    std::cout &lt;&lt; "ExampleAppWindow::update_words(): No visible text view." &lt;&lt; std::endl;
    return;
  }
  auto buffer = view-&gt;get_buffer();

  // Find all words in the text buffer.
  std::set&lt;Glib::ustring&gt; words;
  auto start = buffer-&gt;begin();
  Gtk::TextIter end;
  while (start)
  {
    while (start &amp;&amp; !start.starts_word())
      ++start;

    if (!start)
      break;

    end = start;
    end.forward_word_end();
    if (start == end)
      break;

    auto word = buffer-&gt;get_text(start, end, false);
    words.insert(word.lowercase());
    start = end;
  }

  // Remove old children from the ListBox.
  auto old_children = m_words-&gt;get_children();
  for (auto child : old_children)
  {
    m_words-&gt;remove(*child);
    delete child;
  }

  // Add new child buttons, one per unique word.
  for (const auto&amp; word : words)
  {
    auto row = Gtk::manage(new Gtk::Button(word));
    row-&gt;signal_clicked().connect(sigc::bind(sigc::mem_fun(*this,
      &amp;ExampleAppWindow::on_find_word), row));
    row-&gt;show();
    m_words-&gt;add(*row);
  }
}

void ExampleAppWindow::update_lines()
{
  auto tab = dynamic_cast&lt;Gtk::ScrolledWindow*&gt;(m_stack-&gt;get_visible_child());
  if (!tab)
    return;

  auto view = dynamic_cast&lt;Gtk::TextView*&gt;(tab-&gt;get_child());
  if (!view)
  {
    std::cout &lt;&lt; "ExampleAppWindow::update_lines(): No visible text view." &lt;&lt; std::endl;
    return;
  }
  auto buffer = view-&gt;get_buffer();

  int count = 0;
  auto iter = buffer-&gt;begin();
  while (iter)
  {
    ++count;
    if (!iter.forward_line())
      break;
  }
  m_lines-&gt;set_text(Glib::ustring::format(count));
}
</programlisting>
<para lang="en">File: <filename>exampleapp.gresource.xml</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
&lt;?xml version="1.0" encoding="UTF-8"?&gt;
&lt;gresources&gt;
  &lt;gresource prefix="/org/gtkmm/exampleapp"&gt;
    &lt;file preprocess="xml-stripblanks"&gt;window.ui&lt;/file&gt;
    &lt;file preprocess="xml-stripblanks"&gt;app_menu.ui&lt;/file&gt;
    &lt;file preprocess="xml-stripblanks"&gt;gears_menu.ui&lt;/file&gt;
    &lt;file preprocess="xml-stripblanks"&gt;prefs.ui&lt;/file&gt;
    &lt;file&gt;exampleapp.png&lt;/file&gt;
  &lt;/gresource&gt;
&lt;/gresources&gt;
</programlisting>
<para lang="en">File: <filename>window.ui</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
&lt;?xml version="1.0" encoding="UTF-8"?&gt;
&lt;interface&gt;
  &lt;!-- interface-requires gtk+ 3.8 --&gt;
  &lt;object class="GtkApplicationWindow" id="app_window"&gt;
    &lt;property name="default-width"&gt;600&lt;/property&gt;
    &lt;property name="default-height"&gt;400&lt;/property&gt;
    &lt;child type="titlebar"&gt;
      &lt;object class="GtkHeaderBar" id="header"&gt;
        &lt;property name="title" translatable="yes"&gt;Example Application&lt;/property&gt;
        &lt;property name="visible"&gt;True&lt;/property&gt;
        &lt;property name="show-close-button"&gt;True&lt;/property&gt;
        &lt;property name="decoration-layout"&gt;menu:close&lt;/property&gt;
        &lt;child&gt;
          &lt;object class="GtkLabel" id="lines_label"&gt;
            &lt;property name="visible"&gt;False&lt;/property&gt;
            &lt;property name="label" translatable="yes"&gt;Lines:&lt;/property&gt;
          &lt;/object&gt;
          &lt;packing&gt;
            &lt;property name="pack-type"&gt;start&lt;/property&gt;
          &lt;/packing&gt;
        &lt;/child&gt;
        &lt;child&gt;
          &lt;object class="GtkLabel" id="lines"&gt;
            &lt;property name="visible"&gt;False&lt;/property&gt;
          &lt;/object&gt;
          &lt;packing&gt;
            &lt;property name="pack-type"&gt;start&lt;/property&gt;
          &lt;/packing&gt;
        &lt;/child&gt;
        &lt;child type="title"&gt;
          &lt;object class="GtkStackSwitcher" id="tabs"&gt;
            &lt;property name="visible"&gt;True&lt;/property&gt;
            &lt;property name="stack"&gt;stack&lt;/property&gt;
          &lt;/object&gt;
        &lt;/child&gt;
        &lt;child&gt;
          &lt;object class="GtkToggleButton" id="search"&gt;
            &lt;property name="visible"&gt;True&lt;/property&gt;
            &lt;property name="sensitive"&gt;False&lt;/property&gt;
            &lt;style&gt;
              &lt;class name="image-button"/&gt;
            &lt;/style&gt;
            &lt;child&gt;
              &lt;object class="GtkImage" id="search-icon"&gt;
                &lt;property name="visible"&gt;True&lt;/property&gt;
                &lt;property name="icon-name"&gt;edit-find-symbolic&lt;/property&gt;
                &lt;property name="icon-size"&gt;1&lt;/property&gt;
              &lt;/object&gt;
            &lt;/child&gt;
          &lt;/object&gt;
          &lt;packing&gt;
            &lt;property name="pack-type"&gt;end&lt;/property&gt;
          &lt;/packing&gt;
        &lt;/child&gt;
        &lt;child&gt;
          &lt;object class="GtkMenuButton" id="gears"&gt;
            &lt;property name="visible"&gt;True&lt;/property&gt;
            &lt;property name="direction"&gt;none&lt;/property&gt;
            &lt;property name="use-popover"&gt;True&lt;/property&gt;
            &lt;style&gt;
              &lt;class name="image-button"/&gt;
            &lt;/style&gt;
          &lt;/object&gt;
          &lt;packing&gt;
            &lt;property name="pack-type"&gt;end&lt;/property&gt;
          &lt;/packing&gt;
        &lt;/child&gt;
      &lt;/object&gt;
    &lt;/child&gt;
    &lt;child&gt;
      &lt;object class="GtkBox" id="content_box"&gt;
        &lt;property name="visible"&gt;True&lt;/property&gt;
        &lt;property name="orientation"&gt;vertical&lt;/property&gt;
        &lt;child&gt;
          &lt;object class="GtkSearchBar" id="searchbar"&gt;
            &lt;property name="visible"&gt;True&lt;/property&gt;
            &lt;child&gt;
              &lt;object class="GtkSearchEntry" id="searchentry"&gt;
                &lt;property name="visible"&gt;True&lt;/property&gt;
              &lt;/object&gt;
            &lt;/child&gt;
          &lt;/object&gt;
        &lt;/child&gt;
        &lt;child&gt;
          &lt;object class="GtkBox" id="hbox"&gt;
            &lt;property name="visible"&gt;True&lt;/property&gt;
            &lt;child&gt;
              &lt;object class="GtkRevealer" id="sidebar"&gt;
                &lt;property name="visible"&gt;True&lt;/property&gt;
                &lt;property name="transition-type"&gt;slide-right&lt;/property&gt;
                &lt;child&gt;
                 &lt;object class="GtkScrolledWindow" id="sidebar-sw"&gt;
                   &lt;property name="visible"&gt;True&lt;/property&gt;
                   &lt;property name="hscrollbar-policy"&gt;never&lt;/property&gt;
                   &lt;property name="vscrollbar-policy"&gt;automatic&lt;/property&gt;
                   &lt;child&gt;
                     &lt;object class="GtkListBox" id="words"&gt;
                       &lt;property name="visible"&gt;True&lt;/property&gt;
                       &lt;property name="selection-mode"&gt;none&lt;/property&gt;
                     &lt;/object&gt;
                   &lt;/child&gt;
                 &lt;/object&gt;
                &lt;/child&gt;
              &lt;/object&gt;
            &lt;/child&gt;
            &lt;child&gt;
              &lt;object class="GtkStack" id="stack"&gt;
                &lt;property name="visible"&gt;True&lt;/property&gt;
                &lt;property name="transition-duration"&gt;500&lt;/property&gt;
              &lt;/object&gt;
            &lt;/child&gt;
          &lt;/object&gt;
        &lt;/child&gt;
      &lt;/object&gt;
    &lt;/child&gt;
  &lt;/object&gt;
&lt;/interface&gt;
</programlisting>
<!-- end inserted example code -->

</sect1>

</chapter>

<chapter id="chapter-contributing">
<title>Comment contribuer</title>

<para>Ce document, comme beaucoup d'autres grands logiciels, a été créé gratuitement par des bénévoles. Si vous avez des compétences sur un des aspects de <application>gtkmm</application> qui ne serait pas déjà documenté, il serait aimable à vous d'envisager une contribution à ce document.</para>
<para lang="en">
Ideally, we would like you to <ulink url="http://www.gtkmm.org/bugs.shtml">provide a patch</ulink> to the
<filename>docs/tutorial/C/index-in.docbook</filename> file. This file is currently
in the <literal>gtkmm-documentation</literal> module in GNOME git.
</para>

<para>Si vous décidez de contribuer, veuillez poster votre contribution sur la liste de diffusion de <application>gtkmm</application> à l'adresse <ulink url="mailto:gtkmm-list@gnome.org">&lt;gtkmm-list@gnome.org&gt;</ulink>. Également, prenez note que la totalité de ce document est libre et que tout ajout que vous feriez doit également être libre. Ce qui signifie que quiconque peut se servir de tout ou partie de vos exemples dans ses programmes et que les copies de ce document (y compris votre contribution) peuvent être diffusées gratuitement.</para>

</chapter>

<appendix id="chapter-refptr">
<title>Le pointeur intelligent RefPtr</title>
<para lang="en">
<classname>Glib::RefPtr</classname> is a smartpointer. Specifically, it is a
reference-counting smartpointer. You might be familiar with
<classname>std::auto_ptr&lt;&gt;</classname>, <classname>std::unique_ptr&lt;&gt;</classname>
and <classname>std::shared_ptr&lt;&gt;</classname>, which are also smartpointers.
<classname>Glib::RefPtr&lt;&gt;</classname> is similar to <classname>std::shared_ptr&lt;&gt;</classname>,
which is also reference-counting. <classname>Glib::RefPtr&lt;&gt;</classname> was introduced
long before there was a reference-counting smartpointer in the C++ Standard Library.
</para>

<para lang="en"><ulink url="http://developer.gnome.org/glibmm/2.50/classGlib_1_1RefPtr.html">Reference</ulink></para>

<para>Un pointeur intelligent se comporte plus ou moins comme un pointeur normal. Voici quelques exemples.</para>

<sect1 id="sec-refptr-copying">
    <title>Copie</title>
<para>Vous pouvez copier les <classname>RefPtr</classname>, tout comme des pointeurs normaux. Mais contrairement aux pointeurs normaux, vous n'avez pas à vous soucier de la destruction de l'instance sous-jacente.</para>
<para>
<programlisting lang="en">
Glib::RefPtr&lt;Gdk::Pixbuf&gt; refPixbuf = Gdk::Pixbuf::create_from_file(filename);
Glib::RefPtr&lt;Gdk::Pixbuf&gt; refPixbuf2 = refPixbuf;
</programlisting>
</para>
<para lang="en">
Of course this means that you can store <classname>RefPtr</classname>s in
standard containers, such as <classname>std::vector</classname> or
<classname>std::list</classname>.</para>
<para>
<programlisting lang="en">
std::list&lt; Glib::RefPtr&lt;Gdk::Pixbuf&gt; &gt; listPixbufs;
Glib::RefPtr&lt;Gdk::Pixbuf&gt; refPixbuf = Gdk::Pixbuf::create_from_file(filename);
listPixbufs.push_back(refPixbuf);
</programlisting>
</para>
</sect1>

<sect1 id="sec-refptr-dereferencing"><title>Déréférencement</title>
<para>Vous pouvez déréférencer un pointeur intelligent avec l'opérateur <literal>-&gt;</literal> pour appeler des fonctions membres de l'instance subjacente, comme pour un pointeur normal.</para>
<para>
<programlisting lang="en">
Glib::RefPtr&lt;Gdk::Pixbuf&gt; refPixbuf = Gdk::Pixbuf::create_from_file(filename);
int width = refPixbuf-&gt;get_width();
</programlisting>
</para>
<para>Mais contrairement à la plupart des pointeurs, vous ne pouvez pas utiliser l'opérateur <literal>*</literal> pour avoir accès à l'instance sous-jacente.</para>
<para>
<programlisting lang="en">
Glib::RefPtr&lt;Gdk::Pixbuf&gt; refPixbuf = Gdk::Pixbuf::create_from_file(filename);
Gdk::Pixbuf&amp; underlying = *refPixbuf; //Syntax error - will not compile.
</programlisting>
</para>
</sect1>

<sect1 id="sec-refptr-casting"><title>Forçage de type</title>
<para lang="en">
You can cast <classname>RefPtr</classname>s to base types, just like normal
pointers.
</para>
<para>
<programlisting>
Glib::RefPtr&lt;Gtk::TreeStore&gt; refStore = Gtk::TreeStore::create(columns);
Glib::RefPtr&lt;Gtk::TreeModel&gt; refModel = refStore;
</programlisting>
</para>
<para>Cela signifie que toute fonction membre prenant en paramètre un <literal>const Glib::RefPtr&lt;BaseType&gt;</literal> peut également prendre un <literal>const Glib::RefPtr&lt;DerivedType&gt;</literal>. Le forçage est implicite, tout comme pour un pointeur normal.</para>
<para>Vous pouvez aussi faire un forçage sur un type dérivé, mais la syntaxe est alors différente de celle pour un pointeur normal.</para>
<para>
<programlisting>
Glib::RefPtr&lt;Gtk::TreeStore&gt; refStore =
Glib::RefPtr&lt;Gtk::TreeStore&gt;::cast_dynamic(refModel);
Glib::RefPtr&lt;Gtk::TreeStore&gt; refStore2 =
Glib::RefPtr&lt;Gtk::TreeStore&gt;::cast_static(refModel);
</programlisting>
</para>
</sect1>


<sect1 id="sec-refptr-checking-for-null"><title>Vérification du pointeur NULL </title>
<para>Comme pour les pointeurs normaux, vous pouvez vérifier si un pointeur <classname>RefPtr</classname> ne pointe sur rien.</para>
<para>
<programlisting>
Glib::RefPtr&lt;Gtk::TreeModel&gt; refModel = m_TreeView.get_model();
if(refModel)
{
  int cols_count = refModel-&gt;get_n_columns();
  ...
}
</programlisting>
</para>
<para>Mais contrairement aux pointeurs normaux, les <classname>RefPtr</classname> sont automatiquement initialisés à NULL ; vous n'avez pas à faire cela vous-même.</para>
</sect1>


<sect1 id="sec-refptr-constness"><title>Constance</title>
<para lang="en">
The use of the <literal>const</literal> keyword in C++ is not always clear. You
might not realise that <type>const Something*</type> declares a pointer to a
<type>const Something</type>. The pointer can be changed, but not the
<type>Something</type> that it points to.
</para>
<para>Ainsi, l'équivalent <classname>RefPtr</classname> de <literal>Quelquechose*</literal> pour un paramètre de fonction membre est <literal>const Glib::RefPtr&lt;Quelquechose&gt;&amp;</literal> et l'équivalent de <literal>const Quelquechose*</literal> est <literal>const Glib::RefPtr&lt;const Quelquechose&gt;&amp;</literal>.</para>
<para>Le <literal>const ... &amp;</literal> qui entoure les deux expressions est juste une question d'efficacité, c'est comme utiliser <classname>const std::string&amp;</classname> à la place de <classname>std::string</classname> pour un paramètre de fonction pour éviter une recopie non nécessaire.</para>
</sect1>

</appendix>


<appendix id="chapter-signals">
<title>Signaux</title>

<sect1 id="sec-connecting-signal-handlers">
<title>Connexion aux gestionnaires de signal</title>
<para>Les classes d'éléments graphiques <application>gtkmm</application> ont des fonctions membres d'accès aux signaux, comme <methodname>Gtk::Button::signal_clicked()</methodname>, qui permettent de se connecter au gestionnaire de signal. Grâce à la souplesse de <application>libsigc++</application>, la bibliothèque utilisée par <application>gtkmm</application>, le gestionnaire de signal peut être n'importe quel type de fonction, mais vous souhaiterez probablement utiliser une fonction membre de la classe. Les programmeurs C de <application>GTK+</application> nomment souvent ces gestionnaires de signal « fonctions de rappel » (callback).</para>

<para>Voici un exemple de gestionnaire de signal connecté à un signal :</para>

<para>
<programlisting>
#include &lt;gtkmm/button.h&gt;

void on_button_clicked()
{
    std::cout &lt;&lt; "Hello World" &lt;&lt; std::endl;
}

main()
{
    Gtk::Button button("Hello World");
    button.signal_clicked().connect(sigc::ptr_fun(&amp;on_button_clicked));
}
</programlisting>
</para>

<para>Il y a un certain nombre de choses à considérer à propos de ce code (non fonctionnel). D'abord identifions les parties concernées :</para>

<itemizedlist>
<listitem>

<para>Le gestionnaire de signal est <methodname>on_button_clicked()</methodname>.</para>
</listitem>
<listitem>

<para>Nous le raccrochons à l'objet <classname>Gtk::Button</classname> nommé <varname>button</varname>.</para>
</listitem>
<listitem>

<para>Quand le bouton émet le signal <literal>clicked</literal>, <methodname>on_button_clicked()</methodname> est appelé.</para>
</listitem>

</itemizedlist>

<para>Maintenant ré-examinons la connexion :</para>

<para>
<programlisting>
    ...
    button.signal_clicked().connect(sigc::ptr_fun(&amp;on_button_clicked));
    ...
</programlisting>
</para>

<para>Notez que nous ne passons pas directement un pointeur sur <methodname>on_button_clicked()</methodname> à la fonction membre <methodname>connect()</methodname> du signal. À la place, nous faisons appel à <function>sigc::ptr_fun()</function> et passons le résultat à <methodname>connect()</methodname>.</para>

<para><function>sigc::ptr_fun()</function> génère un objet <classname>sigc::slot</classname>. Un connecteur est un objet qui ressemble et réagit comme une fonction, mais qui, en réalité, est bien un objet. Il est également connu sous le nom d'objet fonction ou « functor ». <function>sigc::ptr_fun()</function> génère un connecteur pour une fonction autonome ou une fonction membre statique. <function>sigc::mem_fun()</function> génère un connecteur pour une fonction membre d'une instance donnée.</para>

<para>Voici un exemple un peu plus développé de connecteurs en action :</para>

<para>
<programlisting>
void on_button_clicked();

class some_class
{
    void on_button_clicked();
};

some_class some_object;

main()
{
    Gtk::Button button;
    button.signal_clicked().connect( sigc::ptr_fun(&amp;on_button_clicked) );
    button.signal_clicked().connect( sigc::mem_fun(some_object,
                                     &amp;some_class::on_button_clicked) );
}
</programlisting>
</para>

<para>Le premier appel à <methodname>connect()</methodname> est identique à celui que nous avons vu la fois précédente ; rien de plus à dire.</para>
<para>Le suivant est plus intéressant. <function>sigc::mem_fun()</function> est appelé avec deux paramètres. Le premier paramètre est <parameter>some_object</parameter>, qui est l'objet sur lequel notre nouveau connecteur pointe. Le second paramètre est un pointeur sur une de ses fonctions membres. Cette version particulière de <function>sigc::mem_fun()</function> crée un connecteur qui, quand il sera « appelé », fera lui-même appel à la fonction membre pointée de l'objet désigné, dans ce cas <methodname>some_object.on_button_clicked()</methodname>.</para>

<para>Autre chose à noter dans cet exemple : nous appelons <methodname>connect()</methodname> deux fois pour le même objet signal. Cela est parfaitement correct — quand le bouton est cliqué, les deux gestionnaires de signal sont appelés.</para>

<para>Nous venons de vous dire que le signal <literal>clicked</literal> d'un bouton s'attend à appeler une fonction membre sans paramètre d'entrée. Tous les signaux ont des exigences de ce type — vous ne pouvez pas accrocher une fonction avec deux paramètres à un signal n'en attendant aucun (sauf si vous utilisez un adaptateur, tels que <function>sigc::bind()</function>, bien entendu). C'est pourquoi il est important de savoir quel type de gestionnaire de signal vous devez connecter à un signal donné.</para>
</sect1>

<sect1 id="sec-writing-signal-handlers">
<title>Écriture de gestionnaires de signal</title>

<para>Pour savoir quel type de gestionnaire de signal vous pouvez connecter, regardez dans la documentation de référence ou dans le fichier d'en-tête. Voici un exemple de déclaration de signal que vous pouvez voir dans les fichiers d'en-tête de <application>gtkmm</application> :</para>

<para>
<programlisting>
Glib::SignalProxy1&lt;bool, Gtk::DirectionType&gt; signal_focus()
</programlisting>
</para>

<para>Outre le nom du signal (<literal>focus</literal>), deux choses sont importantes à noter ici : le nombre suivant le mot <classname>SignalProxy</classname> (1, dans notre cas), et les types de la liste (<literal>bool</literal> et <literal>Gtk::DirectionType</literal>). Le nombre indique le nombre de paramètres que le gestionnaire de signal doit posséder, le premier type, <literal>bool</literal>, est le type de retour du gestionnaire de signal et le suivant, <literal>Gtk::DirectionType</literal>, est le type du premier et unique paramètre de ce signal. En consultant la documentation de référence, vous pouvez également prendre connaissance des noms des arguments.</para>

<para lang="en">
The same principles apply for signals which have more arguments. Here's one
with three (taken from <filename>&lt;gtkmm/textbuffer.h&gt;</filename>):
</para>

<para>
<programlisting lang="en">
Glib::SignalProxy3&lt;void, const TextBuffer::iterator&amp;, const Glib::ustrin&amp;, int&gt; signal_insert();
</programlisting>
</para>

<para>Il est de la même forme. Le nombre 3 à la fin du nom du type indique que le gestionnaire de signal nécessite trois paramètres. Le premier type dans la liste des types est <literal>void</literal>, c'est le type de retour du gestionnaire de signal. Les trois types suivants sont les types des paramètres, dans l'ordre. Notre prototype de gestionnaire de signal ressemble à quelque chose comme :</para>

<para>
<programlisting lang="en">
void on_insert(const TextBuffer::iterator&amp; pos, const Glib::ustring&amp; text, int bytes)
</programlisting>
</para>
</sect1>

<sect1 id="sec-disconnecting-signal-handlers">
<title>Déconnexion des gestionnaires de signal</title>

<para>Examinons à nouveau la fonction membre <literal>connect</literal> d'un signal :</para>

<para>
<programlisting>
sigc::signal&lt;void,int&gt;::iterator signal&lt;void,int&gt;::connect( const sigc::slot&lt;void,int&gt;&amp; );
</programlisting>
</para>

<para lang="en">
Notice that the return value is of type
<classname>sigc::signal&lt;void,int&gt;::iterator</classname>. This can be
implicitly converted into a <classname>sigc::connection</classname> which in
turn can be used to control the connection. By keeping a connection object you
can disconnect its associated signal handler using the method
<methodname>sigc::connection::disconnect()</methodname>.
</para>

</sect1>
<sect1 id="sec-overriding-default-signal-handlers">
<title>Surdéfinition du gestionnaire de signal par défaut</title>

<para>Jusqu'ici nous vous avons montré la réalisation d'actions en réponse à une pression de bouton à l'aide d'un gestionnaire de signal. C'est assurément un bon moyen de réaliser les choses, mais ce n'est pas le seul.</para>

<para>Au lieu de connecter laborieusement les gestionnaires de signal aux signaux, vous pouvez simplement créer une nouvelle classe qui hérite d'un élément graphique — disons, un bouton —, puis surdéfinir le gestionnaire de signal par défaut, tel que Button::on_clicked(). Cela peut se révéler plus simple que d'accrocher des gestionnaires de signal pour chaque chose.</para>

<para>Le sous-classement n'est pas toujours la meilleure façon de réaliser les choses. Il est uniquement utile quand vous souhaitez que l'élément graphique gère son propre signal par lui-même. Si vous souhaitez qu'une autre classe gère le signal, il faut se connecter à un gestionnaire séparé. C'est encore plus vrai si vous voulez que plusieurs objets gèrent le même signal ou si vous voulez qu'un seul gestionnaire de signal réponde au même signal à partir d'objets différents.</para>

<para>Les classes <application>gtkmm</application> ont été conçues dans l'optique de surdéfinitions ; elles comportent des fonctions membres virtuelles spécialement pensées pour être surdéfinies.</para>

<para>Regardons un exemple de surdéfinition :</para>

<para>
<programlisting>
#include &lt;gtkmm/button.h&gt;

class OverriddenButton : public Gtk::Button
{
protected:
    virtual void on_clicked();
}

void OverriddenButton::on_clicked()
{
    std::cout &lt;&lt; "Hello World" &lt;&lt; std::endl;

// appeler la version de la classe de base de la fonction membre:
    Gtk::Button::on_clicked();
}
</programlisting>
</para>

<para>Ici nous définissons une nouvelle classe nommée <classname>OverriddenButton</classname> qui hérite de <classname>Gtk::Button</classname>. La seule chose que nous modifions est la fonction membre <methodname>on_clicked()</methodname> ; cette fonction membre est appelée chaque fois qu'un objet <classname>Gtk::Button</classname> émet le signal <literal>clicked</literal>. Elle affiche « Hello World » sur <literal>stdout</literal>, puis appelle la fonction membre originelle pour que <classname>Gtk::Button</classname> fasse ce qu'il a à faire quand il n'est pas surdéfini.</para>

<para>Il n'est pas toujours nécessaire d'appeler la fonction membre du parent ; certaines fois vous ne le souhaiterez pas. Notez que nous avons appelé la fonction membre du parent <emphasis>après</emphasis> avoir écrit « Hello World », mais nous aurions pu l'appeler avant. Dans cet exemple simple, cela n'a pas beaucoup d'importance, mais parfois si. Avec les signaux, il n'est pas facile de modifier des détails de ce type, et vous pouvez ici faire des choses que vous ne pourrez absolument pas faire avec des gestionnaires de signal connectés : vous pouvez appeler la fonction membre du parent au <emphasis>milieu</emphasis> de votre code personnalisé.</para>

</sect1>

<sect1 id="sec-binding-extra-arguments">
<title>Liaison avec des paramètres supplémentaires</title>
<para lang="en">
If you use one signal handler to catch the same signal from several widgets,
you might like that signal handler to receive some extra information. For
instance, you might want to know which button was clicked. You can do this with
<function>sigc::bind()</function>. Here's some code from the <link linkend="sec-helloworld2">helloworld2</link> example.
<programlisting lang="en">
m_button1.signal_clicked().connect( sigc::bind&lt;Glib::ustring&gt;( sigc::mem_fun(*this, &amp;HelloWorld::on_button_clicked), "button 1") );
</programlisting>
This says that we want the signal to send an extra
<classname>Glib::ustring</classname> argument to the signal handler, and that
the value of that argument should be "button 1". Of course we will need to add
that extra argument to the declaration of our signal handler:
<programlisting lang="en">
virtual void on_button_clicked(Glib::ustring data);
</programlisting>
Of course, a normal "clicked" signal handler would have no arguments.
</para>
<para><function>sigc::bind()</function> n'est pas d'usage courant, mais peut-être le trouverez-vous commode parfois. Si vous êtes un familier de la programmation avec <application>GTK+</application>, vous avez alors probablement noté la similitude avec les paramètres supplémentaires  <literal>gpointer data</literal> que toutes les fonctions de rappel possèdent. Généralement, cette possibilité est utilisée à l'excès dans <application>GTK+</application> pour passer des informations qui devraient être stockées dans une donnée membre d'un élément graphique dérivé, mais la dérivation des éléments graphiques est très difficile en C. Nous avons beaucoup moins besoin de cette façon de faire dans <application>gtkmm</application>.</para>
</sect1>

<sect1 id="sec-xeventsignals">
<title>Signaux des événements X</title>
<para lang="en">
The <classname>Widget</classname> class has some special signals which
correspond to the underlying X-Windows events. These are suffixed by
<literal>_event</literal>; for instance,
<methodname>Widget::signal_button_press_event()</methodname>.
</para>
<para lang="en">
You might occasionally find it useful to handle X events when there's something
you can't accomplish with normal signals. <classname>Gtk::Button</classname>,
for example, does not send mouse-pointer coordinates with its
<literal>clicked</literal> signal, but you could handle
<literal>button_press_event</literal> if you needed this
information. X events are also often used to handle key-presses.
</para>

<para>Ces signaux se comportent de façon légèrement différente. La valeur renvoyée par le gestionnaire de signal indique si l'événement a été pleinement « géré ». Si la valeur est <literal>false</literal>, alors <application>gtkmm</application> passe l'événement au gestionnaire de signal suivant. Si la valeur est <literal>true</literal>, aucun autre gestionnaire de signal n'est appelé.</para>

<para lang="en">
Handling an X event doesn't affect the Widget's other signals. If you handle
<literal>button_press_event</literal> for
<classname>Gtk::Button</classname>, you'll still be able to get the
<literal>clicked</literal> signal. They are emitted at (nearly) the same time.
</para>

<para>Notez aussi que tous les éléments graphiques ne reçoivent pas tous les événements X par défaut. Pour recevoir des événements X supplémentaires, vous pouvez utiliser <methodname>Gtk::Widget::set_events()</methodname> avant d'afficher l'élément graphique ou <methodname>Gtk::Widget::add_events()</methodname> après. Toutefois, certains éléments graphiques doivent préalablement avoir été placés dans un élément graphique <classname>EventBox</classname>. Consultez le chapitre <link linkend="chapter-widgets-without-xwindows">Éléments graphiques sans fenêtre-X</link>.</para>

<para lang="en">
Here's a simple example:
<programlisting lang="en">
bool on_button_press(GdkEventButton* event);
Gtk::Button button("label");
button.signal_button_press_event().connect( sigc::ptr_fun(&amp;on_button_press) );
</programlisting>
</para>
<para>Quand la souris est au dessus du bouton et qu'un bouton de souris est pressé, <methodname>on_button_press()</methodname> est appelé.</para>

<para><literal>GdkEventButton</literal> est une structure contenant les paramètres de l'événement, tels que les coordonnées du pointeur de souris et l'heure où le bouton a été pressé. Les structures <literal>GdkEvent</literal> sont différentes selon les événements.</para>

<sect2 id="signal-handler-sequence">
<title>Séquencement des gestionnaires de signaux</title>
<para lang="en">By default, your signal handlers are called after any previously-connected
signal handlers. However, this can be a problem with the X Event signals. For instance,
the existing signal handlers, or the default signal handler, might return <literal>true</literal>
to stop other signal handlers from being called. To specify that your signal handler
should be called before the other signal handlers, so that it will always be called,
you can specify <literal>false</literal> for the optional <literal>after</literal>
parameter. For instance,
<programlisting lang="en">
button.signal_button_press_event().connect( sigc::ptr_fun(&amp;on_mywindow_button_press), false );
</programlisting>
</para>
<para lang="en">The event is delivered first to the widget the event occurred in. If all
signal handlers in that widget return <literal>false</literal> (indicating that
the event has not been handled), then the signal will be propagated to the parent
widget and emitted there. This continues all the way up to the top-level widget
if no one handles the event. 
</para>
</sect2>

</sect1>

<sect1 id="sec-exceptions-in-signal-handlers">
<title lang="en">Exceptions in signal handlers</title>
<para lang="en">
When a program is aborted because of an unhandled C++ exception, it's sometimes
possible to use a debugger to find the location where the exception was thrown.
This is more difficult than usual if the exception was thrown from a signal handler.
</para>
<para lang="en">
This section describes primarily what you can expect on a Linux system, when you
use <ulink url="http://www.gnu.org/software/gdb/">the gdb debugger</ulink>.
</para>
<para lang="en">
First, let's look at a simple example where an exception is thrown from a normal
function (no signal handler).
<programlisting lang="en">
// without_signal.cc
#include &lt;gtkmm.h&gt;

bool throwSomething()
{
  throw "Something";
  return true;
}

int main(int argc, char** argv)
{
  throwSomething();
  Glib::RefPtr&lt;Gtk::Application&gt; app =
    Gtk::Application::create(argc, argv, "org.gtkmm.without_signal");
  return app-&gt;run();
}
</programlisting>
</para>
<para lang="en">
Here is an excerpt from a <application>gdb</application> session. Only the most
interesting parts of the output are shown.
<programlisting lang="en">
&gt; gdb without_signal
(gdb) run
terminate called after throwing an instance of 'char const*'

Program received signal SIGABRT, Aborted.
(gdb) backtrace
#7  0x08048864 in throwSomething () at without_signal.cc:6
#8  0x0804887d in main (argc=1, argv=0xbfffecd4) at without_signal.cc:12
</programlisting>
You can see that the exception was thrown from <filename>without_signal.cc</filename>,
line 6 (<code>throw "Something";</code>).
</para>
<para lang="en">
Now let's see what happens when an exception is thrown from a signal handler.
Here's the source code.
<programlisting lang="en">
// with_signal.cc
#include &lt;gtkmm.h&gt;

bool throwSomething()
{
  throw "Something";
  return true;
}

int main(int argc, char** argv)
{
  Glib::signal_timeout().connect(sigc::ptr_fun(throwSomething), 500);
  Glib::RefPtr&lt;Gtk::Application&gt; app =
    Gtk::Application::create(argc, argv, "org.gtkmm.with_signal");
  app-&gt;hold();
  return app-&gt;run();
}
</programlisting>
</para>
<para lang="en">
And here's an excerpt from a <application>gdb</application> session.
<programlisting lang="en">
&gt; gdb with_signal
(gdb) run
(with_signal:2703): glibmm-ERROR **:
unhandled exception (type unknown) in signal handler

Program received signal SIGTRAP, Trace/breakpoint trap.
(gdb) backtrace
#2  0x0063c6ab in glibmm_unexpected_exception () at exceptionhandler.cc:77
#3  Glib::exception_handlers_invoke () at exceptionhandler.cc:150
#4  0x0063d370 in glibmm_source_callback (data=0x804d620) at main.cc:212
#13 0x002e1b31 in Gtk::Application::run (this=0x804f300) at application.cc:178
#14 0x08048ccc in main (argc=1, argv=0xbfffecd4) at with_signal.cc:16
</programlisting>
The exception is caught in <application>glibmm</application>, and the program
ends with a call to <function>g_error()</function>. Other exceptions may result
in different behaviour, but in any case the exception from a signal handler is
caught in <application>glibmm</application> or <application>gtkmm</application>, and
<application>gdb</application> can't see where it was thrown.
</para>
<para lang="en">
To see where the exception is thrown, you can use the <application>gdb</application>
command <userinput>catch throw</userinput>.
<programlisting lang="en">
&gt; gdb with_signal
(gdb) catch throw
Catchpoint 1 (throw)
(gdb) run
Catchpoint 1 (exception thrown), 0x00714ff0 in __cxa_throw ()
(gdb) backtrace
#0  0x00714ff0 in __cxa_throw () from /usr/lib/i386-linux-gnu/libstdc++.so.6
#1  0x08048bd4 in throwSomething () at with_signal.cc:6
(gdb) continue
Continuing.
(with_signal:2375): glibmm-ERROR **
unhandled exception (type unknown) in signal handler

Program received signal SIGTRAP, Trace/breakpoint trap.
</programlisting>
</para>
<para lang="en">
If there are many caught exceptions before the interesting uncaught one, this
method can be tedious. It can be automated with the following
<application>gdb</application> commands.
<programlisting lang="en">
(gdb) catch throw
(gdb) commands
(gdb)   backtrace
(gdb)   continue
(gdb)   end
(gdb) set pagination off
(gdb) run
</programlisting>
These commands will print a backtrace from each <code>throw</code> and continue.
The backtrace from the last (or possibly the last but one) <code>throw</code>
before the program stops, is the interesting one.
</para>
</sect1>

</appendix>


<appendix id="chapter-custom-signals">
<title>Création de vos propres signaux</title>
<para>Maintenant que nous avons vu les signaux et les gestionnaires de signal dans <application>gtkmm</application>, vous aimeriez peut-être utiliser la même technique pour interagir entre vos propres classes. C'est vraiment très simple en utilisant directement la bibliothèque <application>libsigc++</application>.</para>
<para>Ce n'est pas à proprement parler un problème <application>gtkmm</application> ou d'interface utilisateur. <application>gtkmm</application> utilise <application>libsigc++</application> pour implémenter ses habillages mandataires du système de signaux <application>GTK+</application>, mais pour des nouveaux signaux non GTK+, vous pouvez créer des signaux C++ purs en utilisant le modèle <classname>sigc::signal&lt;&gt;</classname>.</para>
<para lang="en">
For instance, to create a signal that sends 2 parameters, a <type>bool</type>
and an <type>int</type>, just declare a <classname>sigc::signal</classname>,
like so:
<programlisting lang="en">
sigc::signal&lt;void, bool, int&gt; signal_something;
</programlisting>
</para>
<para lang="en">
You could just declare that signal as a public member variable, but
some people find that distasteful and prefer to make it available via
an accessor method, like so:
<programlisting lang="en">
class Server
{
public:
  //signal accessor:
  typedef sigc::signal&lt;void, bool, int&gt; type_signal_something;
  type_signal_something signal_something();

protected:
  type_signal_something m_signal_something;
};

Server::type_signal_something Server::signal_something()
{
  return m_signal_something;
}
</programlisting>
</para>

<para lang="en">
You can then connect to the signal using the same syntax used when
connecting to <application>gtkmm</application> signals. For instance,
<programlisting lang="en">
server.signal_something().connect(
  sigc::mem_fun(client, &amp;Client::on_server_something) );
</programlisting>
</para>

<sect1 id="chapter-custom-signals-example"><title>Exemple</title>

<para lang="en">
This is a full working example that defines and uses custom signals.
</para>

<para lang="en"><ulink url="http://git.gnome.org/browse/gtkmm-documentation/tree/examples/book/signals/custom/?h=gtkmm-3-22">Source Code</ulink></para>
<!-- start inserted example code -->
<para lang="en">File: <filename>client.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLE_CLIENT_H
#define GTKMM_EXAMPLE_CLIENT_H

#include &lt;sigc++/sigc++.h&gt;

//Client must inherit from sigc::trackable.
//because libsigc++ needs to keep track of the lifetime of signal handlers.
class Client : public sigc::trackable
{
public:
  Client();
  virtual ~Client();

  //Signal handler:
  void on_server_something(bool a, int b);
};

#endif //GTKMM_EXAMPLE_CLIENT_H
</programlisting>
<para lang="en">File: <filename>server.h</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#ifndef GTKMM_EXAMPLE_SERVER_H
#define GTKMM_EXAMPLE_SERVER_H

#include &lt;sigc++/sigc++.h&gt;

class Server
{
public:
  Server();
  virtual ~Server();

  void do_something();

  //signal accessor:
  typedef sigc::signal&lt;void, bool, int&gt; type_signal_something;
  type_signal_something signal_something();

protected:
  type_signal_something m_signal_something;
};

#endif //GTKMM_EXAMPLE_SERVER_H
</programlisting>
<para lang="en">File: <filename>main.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "server.h"
#include "client.h"
#include &lt;iostream&gt;

int main(int, char**)
{
  Server server;
  Client client;

  //Connect a Server signal to the signal handler in Client.
  server.signal_something().connect(sigc::mem_fun(client,
              &amp;Client::on_server_something) );

  std::cout &lt;&lt; "Before Server::do_something()" &lt;&lt; std::endl;

  //Tell the server to do something that will eventually cause it to emit the
  //"something" signal.
  server.do_something();    // Client::on_server_something() will run before
                            // Server::do_something() has completed.

  std::cout &lt;&lt; "After Server::do_something()" &lt;&lt; std::endl;

  return 0;
}
</programlisting>
<para lang="en">File: <filename>client.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "client.h"
#include &lt;iostream&gt;

Client::Client()
{
}

Client::~Client()
{
}

void Client::on_server_something(bool a, int b)
{
  std::cout &lt;&lt; "Client::on_server_something() called with these parameters: "
      &lt;&lt; a &lt;&lt; ", " &lt;&lt; b &lt;&lt; std::endl;
}
</programlisting>
<para lang="en">File: <filename>server.cc</filename> (For use with gtkmm 3, not gtkmm 2)
</para>
<programlisting lang="en">
#include "server.h"
#include &lt;iostream&gt;

Server::Server()
{
}

Server::~Server()
{
}

Server::type_signal_something Server::signal_something()
{
  return m_signal_something;
}

void Server::do_something()
{
  m_signal_something.emit(false, 5);
}

</programlisting>
<!-- end inserted example code -->

</sect1>

</appendix>




<appendix id="sec-signals-comparison">
<title>Comparaison avec les autres systèmes de signalisation</title>
<para>(En aparté : <application>GTK+</application> appelle ce mécanisme « signalisation » ; le regard avisé du lecteur ayant un certaine expérience des boîtes à outils d'interfaces utilisateur ne manquera pas de noter que cette même conception est souvent rencontrée sous l'appellation de « broadcaster-listener » (émetteur-récepteur) (comme dans l'architecture PowerPlant de Metrowerks pour le Macintosh). Cela fonctionne tout à fait de la même façon : on met en place des <literal>broadcasters</literal> (émetteurs), puis on y connecte des <literal>listeners</literal> (récepteurs) ; l'émetteur conserve une liste des objets qui l'écoutent, et quand quelqu'un donne un message à l'émetteur, il appelle tous les objets de sa liste avec le message. Dans <application>gtkmm</application>, les objets signaux jouent le rôle d'émetteurs et les connecteurs celui de récepteurs — en quelque sorte. Plus à ce sujet plus tard.)</para>
<para>Les gestionnaires de signaux <application>gtkmm</application> sont fortement typés, alors que le code C de <application>GTK+</application> vous autorise à connecter une fonction de rappel avec un nombre de paramètres erroné ou de mauvais type, déclenchant une erreur de segmentation lors de l'exécution. Et, contrairement à <application>Qt</application>, <application>gtkmm</application> réalise cela sans modifier le langage C++.</para>
<para>Retour à propos de la surdéfinition des gestionnaires de signal : vous pouvez également réaliser cette surdéfinition en restant dans le domaine strict du C de GTK+ ; le système d'objets de GTK est fait pour cela. Mais dans GTK+, vous devez cheminer par des procédures complexes pour obtenir des fonctionnalités telle que l'héritage et la surdéfinition. En C++, c'est simple, car ces fonctionnalités sont prises en charge dans le langage lui-même ; vous pouvez déléguer au compilateur le soin de faire le « sale boulot ».</para>
<para>C'est un des aspects où la beauté du C++ ressort vraiment. Quelqu'un songerait-il à sous-classer un élément graphique GTK+ uniquement pour surdéfinir ses fonctions membres d'action ? Ce serait s'exposer à trop d'ennuis. Dans GTK+, vous utilisez pratiquement toujours les signaux pour exécuter quelque chose, à moins que vous n'écriviez un nouvel élément graphique. Mais comme la surdéfinition des fonctions membres est si facile en C++, il est tout à fait pratique — et sensé — de sous-classer un bouton pour cette seule raison.</para>
</appendix>

<appendix id="sec-windows-installation">
        <title><application>gtkmm</application> et Win32</title>
    <para>Un des avantages majeurs de <application>gtkmm</application> est que <application>gtkmm</application> est multiplate-forme. Les programmes <application>gtkmm</application> écrits sur des plate-formes telles que GNU/Linux peuvent généralement être portées sur Windows (et vice versa) avec peu de modifications des sources.</para>
    <para lang="en">
      <application>gtkmm</application> currently works with the <ulink url="http://mingw.org/">MingW/GCC3.4 compiler</ulink> and Microsoft
      Visual C++ 2005 or later (including the freely available express
      editions) on the Windows platform. There is an
      <ulink url="ftp://ftp.gnome.org/pub/GNOME/binaries/win32/gtkmm">
      installer</ulink> available for gtkmm on Microsoft Windows. Refer to
      <ulink url="https://wiki.gnome.org/Projects/gtkmm/MSWindows/">
      https://wiki.gnome.org/Projects/gtkmm/MSWindows</ulink> for instructions how to
      use it.
    </para>
  <sect1 id="sec-building-on-win32">
        <title>Construction de <application>gtkmm</application> sur Win32</title>
    <para lang="en">Please see <ulink url="https://wiki.gnome.org/Projects/gtkmm/MSWindows/BuildingGtkmm">
    https://wiki.gnome.org/Projects/gtkmm/MSWindows/BuildingGtkmm</ulink> for instructions on how to build gtkmm on Windows.
    </para>

    </sect1>
</appendix>

<appendix id="chapter-working-with-source">
  <title>Travail avec le code source de gtkmm</title>
  <para lang="en">
    If you are interested in helping out with the development of <application>gtkmm</application>, or
    fixing a bug in <application>gtkmm</application>, you'll probably need to build the development
    version of <application>gtkmm</application>. However, you should not install a development version over
    your stable version. Instead, you should install it alongside your existing <application>gtkmm</application>
    installation, in a separate path.
  </para>
  <para lang="en">
    The easiest way to do this is using <ulink url="https://wiki.gnome.org/Projects/Jhbuild">jhbuild</ulink>.
    <application>jhbuild</application> is a program that makes building GNOME
    software much easier by calculating dependencies and building things in the
    correct order. This section will give a brief explanation of how to set up
    <application>jhbuild</application> to build and install <application>gtkmm</application> from the
    source repository (git). For up-to-date information
    on <application>jhbuild</application>, please refer to the <ulink url="http://developer.gnome.org/jhbuild/unstable/">jhbuild manual</ulink>.
    If you need assistance using <application>jhbuild</application>, you should
    ask for help on the <ulink url="http://mail.gnome.org/mailman/listinfo/gnome-love">gnome-love
      mailing list</ulink>.
  </para>
  <note>
    <para lang="en">
    Note that to build <application>gtkmm</application> from git, you'll often need to build many of its
    dependencies from git as well. <application>jhbuild</application> makes
    this easier than it would normally be, but it will take quite a while to
    build and install them all. You will probably encounter build problems,
    though these will usually be corrected quickly if you report them.
    </para>
  </note>
  <sect1 id="sec-setting-up-jhbuild">
    <title>Paramétrage de jhbuild</title>
    <para lang="en">
      To set up <application>jhbuild</application>, follow the basic
      installation instructions from the <ulink url="http://developer.gnome.org/jhbuild/unstable/">jhbuild manual</ulink>.
      After you have installed <application>jhbuild</application>, you
      should copy the sample <application>jhbuild</application> configuration
      file into your home directory by executing the following command from the
      <application>jhbuild</application> directory:
      <screen lang="en">$ cp examples/sample.jhbuildrc ~/.jhbuildrc</screen>
    </para>
    <para lang="en">
      The <application>gtkmm</application> module is defined in the
      <filename>gnome-suites-core-deps-3.x.modules</filename> moduleset, so edit your
      <filename>.jhbuildrc</filename> file and set your moduleset setting to the
      latest version e.g. like so:
      <programlisting lang="en">moduleset = 'gnome-suites-core-deps-3.12'</programlisting>
    </para>
    <para lang="en">
      After setting the correct moduleset, you need to tell
      <application>jhbuild</application> which module or modules to build. To
      build <application>gtkmm</application> and all of its dependencies, set <varname>modules</varname>
      like so:
      <programlisting lang="en">modules = [ 'gtkmm' ]</programlisting>
    </para>
    <para lang="en">
      You can build several modules by setting the
      <varname>modules</varname> variable to a meta-package, e.g.
      <literal>meta-gnome-core</literal>, or listing more than one module name.
      The <varname>modules</varname> variable specifies which modules will be
      built when you don't explicitly specify anything on the command line. You
      can always build a different moduleset later by specifying it on the
      commandline (e.g. <command>jhbuild build gtkmm</command>).
    </para>
    <important>
      <title>Définition d'un préfixe</title>
      <para lang="en">
        By default, <application>jhbuild</application>'s configuration is
        configured to install all software built with
        <application>jhbuild</application> under the
        <filename>/opt/gnome</filename> prefix. You can choose a different
        prefix, but it is recommended that you keep this prefix different from
        other software that you've installed (don't set it to
        <filename>/usr</filename>!) If you've followed the jhbuild instructions
        then this prefix belongs to your user, so you don't need to run jhbuild
        as <literal>root</literal>.
      </para>
    </important>
    <para lang="en">
      When you downloaded <application>jhbuild</application> from the git repository,
      you got a number of <filename>.modules</filename> files, specifying
      dependencies between modules. By default <application>jhbuild</application>
      does not use the downloaded versions of these files, but reads the
      latest versions in the git repository. This is usually what you want.
      If you don't want it, use the <varname>use_local_modulesets</varname>
      variable in <filename>.jhbuildrc</filename>.
    </para>
  </sect1>
  <sect1 id="sec-installing-jhbuild">
    <title>Installation et utilisation de la version git de <application>gtkmm</application></title>
    <para lang="en">
      Once you've configured <application>jhbuild</application> as described
      above, building <application>gtkmm</application> should be relatively straightforward. The first
      time you run <application>jhbuild</application>, you should run the
      following sequence of commands to ensure that
      <application>jhbuild</application> has the required tools and verify that
      it is set up correctly:
      <screen lang="en">$ jhbuild bootstrap
$ jhbuild sanitycheck</screen>
    </para>
    <sect2 id="jhbuild-installing-gtkmm">
      <title>Installation de <application>gtkmm</application> avec <application>jhbuild</application></title>
      <para>Si tout fonctionne correctement, vous devez être capable de construire <application>gtkmm</application> et toutes ses dépendances à partir du dépôt git en exécutant la commande <command>jhbuild build</command> (ou, si vous n'avez pas précisé <application>gtkmm</application> dans la variable <varname>modules</varname>, avec la commande <command>jhbuild build gtkmm</command>). </para>
      <para lang="en">
        This command will build and install a series of modules and will probably
        take quite a long time the first time through. After the first time,
        however, it should go quite a bit faster since it only needs to rebuild
        files that changed since the last build. Alternatively, after you've
        built and installed <application>gtkmm</application> the first time, you can rebuild <application>gtkmm</application> by
        itself (without rebuilding all of its dependencies) with the command
        <command>jhbuild buildone gtkmm</command>.
      </para>
    </sect2>
    <sect2 id="jhbuild-using-gtkmm">
      <title>Utilisation de la version git de <application>gtkmm</application></title>
      <para>Après avoir installé la version git de <application>gtkmm</application>, vous êtes prêt à commencer à l'utiliser et le tester. Pour utiliser la nouvelle version de <application>gtkmm</application> que vous venez d'installer, il est nécessaire de paramétrer certaines variables d'environnement pour que le script <filename>configure</filename> sache où trouver les nouvelles librairies. Fort heureusement, <application>jhbuild</application> offre une solution élégante à ce problème. L'exécution de la commande <command>jhbuild shell</command> ouvre un nouveau shell avec toutes les variables d'environnement correctement fixées. Maintenant si vous re-configurez et construisez votre projet comme vous avez l'habitude de faire, il fera l'édition des liens avec les bibliothèques nouvellement installées. Pour revenir dans votre environnement précédent, sortez simplement du shell <application>jhbuild</application>.</para>
      <para>Après avoir construit votre logiciel, vous devez également le lancer dans l'environnement jhbuild. Pour ce faire, vous pouvez une nouvelle fois utiliser la commande <command>jhbuild shell</command> pour ouvrir un nouveau shell dans l'environnement <application>jhbuild</application>. Autrement, vous pouvez lancer une commande à effet unique dans l'environnement <application>jhbuild</application> avec la commande suivante : <command>jhbuild run command-name</command>. Dans ce cas, la commande se déroule avec les variables d'environnement correctement fixées, mais elle retourne dans l'environnement précédent à la sortie du programme.</para>

    </sect2>
  </sect1>
</appendix>

<appendix id="chapter-wrapping-c-libraries">
<title>Habillage des bibliothèques C avec gmmproc</title>
<para><application>gtkmm</application> se sert de l'utilitaire <command>gmmproc</command> pour générer la plus grande partie de son code source, en utilisant les fichiers .defs définissant les API des bibliothèques fondées sur <classname>GObject</classname>. Il est donc facile de créer des habillages supplémentaires dans le style gtkmm pour les autres bibliothèques fondées sur glib/GObject.</para>
<para lang="en">This involves a variety of tools, some of them crufty, but at least
    they work, and has been used successfully by several
    projects.</para>

<sect1 id="sec-wrapping-build-structure">
<title>La structure de construction</title>
<para>Générer du code source pour un habillage d'API dans le style gtkmm requiert l'utilisation d'outils tels que <command>gmmproc</command> et <filename>generate_wrap_init.pl</filename>. En théorie, vous pouvez écrire vos propres fichiers de construction pour utiliser ces outils de manière appropriée, mais l'utilisation de l'infrastructure de construction fournie par le module mm-common est un meilleur choix. Prendre un module de liaison existant à titre d'exemple et l'examiner est un bon début.</para>
<para lang="en">For instance, let's pretend that we are wrapping a C library called
    libsomething. It provides a <classname>GObject</classname>-based API with
    types named, for instance, <classname>SomeWidget</classname> and
    <classname>SomeStuff</classname>.</para>

<sect2 id="copying-skeleton-project">
<title>Copie du squelette du projet</title>

<para lang="en">Typically our wrapper library would be called libsomethingmm. We can start by
  copying the <ulink url="http://git.gnome.org/browse/mm-common/tree/skeletonmm">skeleton
  source tree</ulink> from the mm-common module.
<programlisting lang="en">
  $ git clone git://git.gnome.org/mm-common
  $ cp -a mm-common/skeletonmm libsomethingmm
</programlisting>
</para>
<para lang="en">This provides a directory structure for the source .hg and .ccg files and the generated .h
  and .cc files, with <filename>filelist.am</filename> Automake include files that can specify the
  various files in use, in terms of generic Automake variables. The directory structure usually
  looks like this, after we have renamed the directories appropriately:
<itemizedlist>
    <listitem><para lang="en"><filename>libsomethingmm</filename>: The top-level directory.</para>
     <itemizedlist>
         <listitem><para lang="en"><filename>libsomething</filename>: Contains the main include file and the pkg-config .pc file.</para>
         <itemizedlist>
             <listitem><para lang="en"><filename>src</filename>: Contains .hg and .ccg source files.</para></listitem>
             <listitem><para lang="en"><filename>libsomethingmm</filename>: Contains generated and hand-written .h and .cc files.</para>
             <itemizedlist>
                 <listitem><para lang="en"><filename>private</filename>: Contains generated <filename>*_p.h</filename> files.</para></listitem>
             </itemizedlist>
           </listitem>
         </itemizedlist>
       </listitem>
    </itemizedlist>
  </listitem>
</itemizedlist>
</para>

<para lang="en">As well as renaming the directories, we should rename some of the source
    files. For instance:
<programlisting lang="en">
$ for f in $(find libsomethingmm -depth -name '*skeleton*'); do \
    d="${f%/*}"; b="${f##*/}"; mv "$f" "$d/${b//skeleton/libsomething}"; \
  done
</programlisting>
A number of the skeleton files must still be filled in with project-specific content later.
</para>
<para>Notez que les fichiers avec l'extension <filename>.in</filename> seront utilisés pour générer des fichiers de même nom, mais sans extension, en remplaçant certaines variables par leur vraie valeur pendant la phase de traitement par le script configure.</para>
</sect2>

<sect2 id="modifying-build-files">
<title>Modification des fichiers de construction</title>

<para lang="en">Now we edit the files to adapt them to our needs. You might prefer to use a multiple-file
  search-replace utility for this, such as <command>regexxer</command>. Note that nearly all of the
  files provided with the skeleton source tree contain placeholder text. Thus, the substitutions
  should be performed globally, and not be limited to the Automake and Autoconf files.</para>
<para>Toutes les mentions de <varname>skeleton</varname> doivent être remplacées par le nom adéquat de la bibliothèque C que vous habillez, comme « something » ou « libsomething ». De la même manière, toutes les occurrences de <varname>SKELETON</varname> doivent être remplacées par « SOMETHING » ou « LIBSOMETHING » et celles de <varname>Skeleton</varname> par « Something ».</para>
<para>De même, remplacez toutes les occurrences de <varname>Joe Hacker</varname> par le nom du détenteur du copyright — vous, probablement. Faites de même pour l'adresse courriel <varname>joe@example.com</varname>.</para>

<sect3 id="modifying-configure.ac">
<title>configure.ac</title>
<para lang="en">In <filename>configure.ac</filename>,
<itemizedlist>
  <listitem><para lang="en">The <function>AC_CONFIG_SRCDIR()</function> line must mention a file
      in our source tree. We can edit this later if we don't yet know the
      names of any of the files that we will create.</para></listitem>
  <listitem><para lang="en">It is common for binding modules to track the version number
      of the library they are wrapping. So, for instance, if the C library is
      at version 1.23.4, then the initial version of the binding module would
      be 1.23.0. However, avoid starting with an even minor version number as
      that usually indicates a stable release.</para></listitem>
  <listitem><para lang="en">The <function>AC_CONFIG_HEADERS()</function> line is used to
      generate two or more configuration header files. The first header file
      in the list contains all configuration macros which are set during the
      configure run. The remaining headers in the list contain only a subset
      of configuration macros and their corresponding <filename>config.h.in</filename>
      file will not be autogenerated. The reason for this separation is that
      the namespaced configuration headers are installed with your library and
      define publically visible macros.</para></listitem>
  <listitem><para lang="en">The <function>AC_SUBST([SOMETHINGMM_MODULES], ['...'])</function>
      line may need to be modified to check for the correct dependencies.</para></listitem>
  <listitem><para lang="en">The <function>AC_CONFIG_FILES()</function> block must mention
      the correct directory names, as described above.</para></listitem>
</itemizedlist>
</para>
</sect3>

<sect3 id="modifying-makefile.am">
<title>Fichiers Makefile.am</title>
<para lang="en">Next we must adapt the various <filename>Makefile.am</filename> files:
  <itemizedlist>
    <listitem><para lang="en">In <filename>skeleton/src/Makefile.am</filename> we
            must mention the correct values for the generic variables that are used
            elsewhere in the build system:</para>
        <variablelist>
            <varlistentry>
                <term lang="en"><varname>binding_name</varname></term>
                <listitem><para lang="en">The name of the library, such as
                        libsomethingmm.</para></listitem>
            </varlistentry>
            <varlistentry>
                <term lang="en"><varname>wrap_init_flags</varname></term>
                <listitem><para lang="en">Additional command-line flags passed to the
                    <filename>generate_wrap_init.pl</filename> script, such
                    as the C++ namespace and the parent directory prefix of
                    include files.</para></listitem>
            </varlistentry>
        </variablelist>
    </listitem>
    <listitem><para lang="en">In <filename>skeleton/skeletonmm/Makefile.am</filename> we
            must mention the correct values for the generic variables that are used
            elsewhere in the build system:</para>
      <variablelist>
        <varlistentry>
          <term lang="en"><varname>lib_LTLIBRARIES</varname></term>
          <listitem><para lang="en">This variable must mention the correct library
              name, and this library name must be used to form the
              <varname>_SOURCES</varname>, <varname>_LDFLAGS</varname>, and
              <varname>_LIBADD</varname> variable names. It is permissible to
              use variables substituted by <filename>configure</filename> like
              <varname>@SOMETHINGMM_API_VERSION@</varname> as part of the
              variable names.</para></listitem>
        </varlistentry>
        <varlistentry>
          <term lang="en"><varname>AM_CPPFLAGS</varname></term>
          <listitem><para lang="en">The command line options passed to the C
              preprocessor.</para></listitem>
        </varlistentry>
        <varlistentry>
          <term lang="en"><varname>AM_CXXFLAGS</varname></term>
          <listitem><para lang="en">The command line options passed to the C++
              compiler.</para></listitem>
        </varlistentry>
      </variablelist>
    </listitem>
  </itemizedlist>
</para>
</sect3>

<sect3 id="creating-hg-ccg">
<title>Création des fichiers .hg et .ccg</title>
<para>Vous devez maintenant créer vos premiers fichiers <filename>.hg</filename> et <filename>.ccg</filename> pour habiller quelques objets dans la librairie C. Il y a une paire de fichiers sources à titre d'exemple : <filename>skeleton.ccg</filename> et <filename>skeleton.hg</filename>. Faites des copies de ces fichiers si nécessaire.</para>
<para>Il faut mentionner tous les fichiers <filename>.hg</filename> et <filename>.ccg</filename> dans le fichier <filename>skeleton/src/filelist.am</filename>, traditionnellement dans la variable <varname>files_hg</varname>.</para>
<para>Tout fichier source <filename>.h</filename> et <filename>.cc</filename> non généré automatiquement doit être placé dans <filename>skeleton/skeletonmm/</filename> et énuméré dans <filename>skeleton/skeletonmm/filelist.am</filename>, traditionnellement dans les variables <varname>files_extra_h</varname> et <varname>files_extra_cc</varname>.</para>
<para>Dans le paragraphe <link linkend="sec-wrapping-hg-files">Fichiers .hg et .ccg</link> vous pouvez voir la syntaxe utilisée dans ces fichiers.</para>
</sect3>
</sect2>
</sect1>

<sect1 id="sec-wrapping-defs-files">
<title>Génération des fichiers .defs</title>
<para lang="en">The <filename>.defs</filename> files are text files, in a lisp format, that describe the API
  of a C library, including its
<itemizedlist>
  <listitem><para lang="en">objects (GObjects, widgets, interfaces, boxed-types and plain structs)</para></listitem>
  <listitem><para lang="en">functions</para></listitem>
  <listitem><para lang="en">enums</para></listitem>
  <listitem><para lang="en">signals</para></listitem>
  <listitem><para lang="en">properties</para></listitem>
  <listitem><para lang="en">vfuncs</para></listitem>
</itemizedlist>
</para>
<para lang="en">At the moment, we have separate tools for generating different parts of
  these <filename>.defs</filename>, so we split them up into separate files.
  For instance, in the <filename>gtk/src</filename> directory of the <application>gtkmm</application>
  sources, you will find these files:
    <variablelist>
        <varlistentry>
            <term lang="en"><filename>gtk.defs</filename></term>
            <listitem><para lang="en">Includes the other files.</para></listitem>
        </varlistentry>
        <varlistentry>
            <term lang="en"><filename>gtk_methods.defs</filename></term>
            <listitem><para lang="en">Objects and functions.</para></listitem>
        </varlistentry>
        <varlistentry>
            <term lang="en"><filename>gtk_enums.defs</filename></term>
            <listitem><para lang="en">Enumerations.</para></listitem>
        </varlistentry>
        <varlistentry>
            <term lang="en"><filename>gtk_signals.defs</filename></term>
            <listitem><para lang="en">Signals and properties.</para></listitem>
        </varlistentry>
        <varlistentry>
            <term lang="en"><filename>gtk_vfuncs.defs</filename></term>
            <listitem><para lang="en">vfuncs (function pointer member fields in structs), written by hand.</para></listitem>
        </varlistentry>
    </variablelist>
</para>
<para lang="en">The <filename>skeletonmm/codegen/generate_defs_and_docs.sh</filename> script
generates all <filename>.defs</filename> files and the <filename>*_docs.xml</filename> file,
described in the <link linkend="sec-wrapping-documentation">Documentation</link> section.
</para>

<sect2 id="generating-defs-methods">
<title>Génération des .defs pour les fonctions membres</title>
<para lang="en">This <filename>.defs</filename> file describes objects and their functions.
  It is generated by the <command>h2def.py</command> script which you can find in
  glibmm's <filename>tools/defs_gen</filename> directory. For instance,
<programlisting lang="en">
$ ./h2def.py /usr/include/gtk-3.0/gtk/*.h &gt; gtk_methods.defs
</programlisting>
</para>
</sect2>

<sect2 id="generating-defs-enums">
<title>Génération des .defs pour les énumérations</title>
<para lang="en">This <filename>.defs</filename> file describes enum types and their possible
  values. It is generated by the <filename>enum.pl</filename> script which you can
  find in glibmm's <filename>tools</filename> directory. For instance,
<programlisting lang="en">
$ ./enum.pl /usr/include/gtk-3.0/gtk/*.h &gt; gtk_enums.defs
</programlisting>
</para>
</sect2>

<sect2 id="generating-defs-signals-properties">
<title>Génération des .defs pour les signaux et les propriétés</title>
<para lang="en">This <filename>.defs</filename> file describes signals and properties. It is
  generated by the special <filename>generate_extra_defs</filename> utility that is in every
  wrapping project, such as <filename>gtkmm/tools/extra_defs_gen/</filename>.
  For instance
<programlisting lang="en">
$ cd tools/extra_defs_gen
$ ./generate_extra_defs &gt; gtk_signals.defs
</programlisting>
</para>
<para>Vous devez rédiger le code source de votre propre outil <filename>generate_extra_defs</filename> pour générer les fichiers <filename>.defs</filename> des types C GObject que vous souhaitez habiller. Dans l'arborescence des sources squelettes, le fichier source s'appelle <filename>codegen/extradefs/generate_extra_defs_skeleton.cc</filename>. Si ce n'est pas déjà fait, le fichier doit être renommé en remplaçant la variable de substitution <varname>skeleton</varname> par le nom de base de la nouvelle liaison. Le fichier <filename>codegen/Makefile.am</filename> doit également citer le nouveau nom du fichier source.</para>
<para lang="en">Then edit the <filename>.cc</filename> file to specify the correct types.
  For instance, your <function>main()</function> function might look like this:
<programlisting lang="en">
#include &lt;libsomething.h&gt;

int main(int, char**)
{
  something_init();

  std::cout &lt;&lt; get_defs(SOME_TYPE_WIDGET)
            &lt;&lt; get_defs(SOME_TYPE_STUFF);
  return 0;
}
</programlisting>
</para>
</sect2>

<sect2 id="writing-defs-vfuncs">
<title>Écriture des .defs pour les fonctions virtuelles</title>
<para lang="en">
  This <filename>.defs</filename> file describes virtual functions (vfuncs).
  It must be written by hand. There is the skeleton file
  <filename>skeleton/src/skeleton_vfunc.defs</filename> to start from. You can also look
  at <application>gtkmm</application>'s <filename>gtk/src/gtk_vfuncs.defs</filename> file.
</para>
</sect2>

</sect1>

<sect1 id="sec-wrapping-hg-files">
    <title>Les fichiers .hg et .ccg</title>
    <para>Les fichiers sources .hg et .ccg ressemblent tout à fait aux fichiers sources .h et .cc du C++, mais il comportent des macros supplémentaires, telles que <function>_CLASS_GOBJECT()</function> et <function>_WRAP_METHOD()</function>, à partir desquelles <command>gmmproc</command> génére le code source C++ approprié, habituellement à la même position dans l'en-tête. Tout code source C++ sera copié mot pour mot dans le fichier .h ou .cc correspondant.</para>
    <para lang="en">A .hg file will typically include some headers
        and then declare a class, using some macros to add API or behaviour to
        this class. For instance, <application>gtkmm</application>'s <filename>button.hg</filename> looks
        roughly like this:

<programlisting lang="en">
#include &lt;gtkmm/bin.h&gt;
#include &lt;gtkmm/activatable.h&gt;
_DEFS(gtkmm,gtk)
_PINCLUDE(gtkmm/private/bin_p.h)

namespace Gtk
{

class Button
  : public Bin,
    public Activatable // Activatable is deprecated. Will be replaced at ABI break.
{
  _CLASS_GTKOBJECT(Button,GtkButton,GTK_BUTTON,Gtk::Bin,GtkBin)
  _IMPLEMENTS_INTERFACE(Activatable)
public:

  _CTOR_DEFAULT
  explicit Button(const Glib::ustring&amp; label, bool mnemonic = false);

  _WRAP_METHOD(void set_label(const Glib::ustring&amp; label), gtk_button_set_label)

  ...

  _WRAP_SIGNAL(void clicked(), "clicked")

  ...

  _WRAP_PROPERTY("label", Glib::ustring)
};

} // namespace Gtk
</programlisting>
</para>
<para lang="en">The macros in this example do the following:
<variablelist>
    <varlistentry>
        <term lang="en"><function>_DEFS()</function></term>
        <listitem><para lang="en">Specifies the destination directory for generated sources, and the name of the main .defs file that <command>gmmproc</command> should parse.</para></listitem>
    </varlistentry>
    <varlistentry>
        <term lang="en"><function>_PINCLUDE()</function></term>
        <listitem><para lang="en">Tells <command>gmmproc</command> to include a header in the generated private/button_p.h file.</para></listitem>
    </varlistentry>
    <varlistentry>
        <term lang="en"><function>_CLASS_GTKOBJECT()</function></term>
        <listitem><para lang="en">Tells <command>gmmproc</command> to add some typedefs, constructors, and standard methods to this class, as appropriate when wrapping a widget.</para></listitem>
    </varlistentry>
    <varlistentry>
        <term lang="en"><function>_IMPLEMENTS_INTERFACE()</function></term>
        <listitem><para lang="en">Tells <command>gmmproc</command> to add initialization code for the interface.</para></listitem>
    </varlistentry>
    <varlistentry>
        <term lang="en"><function>_CTOR_DEFAULT</function></term>
        <listitem><para lang="en">Add a default constructor.</para></listitem>
    </varlistentry>
    <varlistentry>
        <term lang="en"><function>_WRAP_METHOD()</function>,
            <function>_WRAP_SIGNAL()</function>,
            <function>_WRAP_PROPERTY()</function>, and
            <function>_WRAP_CHILD_PROPERTY()</function></term>
        <listitem><para lang="en">Add methods to wrap parts of the C API.</para></listitem>
    </varlistentry>
</variablelist>
</para>
<para lang="en">The .h and .cc files will be generated from the .hg and .ccg files by
    processing them with <command>gmmproc</command> like so, though this happens
    automatically when using the above build structure:
<programlisting lang="en">
$ cd gtk/src
$ /usr/lib/glibmm-2.4/proc/gmmproc -I ../../tools/m4 --defs . button . ./../gtkmm
</programlisting>
</para>
<para>Notez que nous appelons <command>gmmproc</command> avec comme paramètre le chemin vers les fichiers .m4 convertis, le chemin vers les fichiers .defs, le nom du fichier .hg, le répertoire source et le répertoire destination.</para>
<para>Nous nous abstenons d'inclure le fichier d'en-tête C à partir de l'en-tête C++ pour éviter de polluer l'espace de noms global et pour éviter d'exporter des API publiques non nécessaires. Mais vous aurez besoin d'inclure les en-têtes C nécessaires à partir de votre fichier .ccg.</para>

<para>Les macros sont expliquées plus en détail dans les paragraphes suivants.</para>

<sect2 id="gmmproc-m4-conversions">
<title>Conversions m4</title>
<para lang="en">The macros that you use in the .hg and .ccg files often need to know how
to convert a C++ type to a C type, or vice-versa. gmmproc takes this information
from an .m4 file in your <literal>tools/m4/</literal> directory. This allows it
to call a C function in the implementation of your C++ method, passing the
appropriate parameters to that C functon. For instance, this
tells gmmproc how to convert a GtkTreeView pointer to a Gtk::TreeView pointer:
<programlisting lang="en">
_CONVERSION(`GtkTreeView*',`TreeView*',`Glib::wrap($3)')
</programlisting>
</para>

<para><literal>$3</literal> sera remplacé par le nom du paramètre lorsque cette conversion est utilisée par gmmproc.</para>

<para lang="en">
Some extra macros make this easier and consistent. Look in gtkmm's .m4 files
for examples. For instance:
<programlisting lang="en">
_CONVERSION(`PrintSettings&amp;',`GtkPrintSettings*',__FR2P)
_CONVERSION(`const PrintSettings&amp;',`GtkPrintSettings*',__FCR2P)
_CONVERSION(`const Glib::RefPtr&lt;Printer&gt;&amp;',`GtkPrinter*',__CONVERT_REFPTR_TO_P($3))
</programlisting>
</para>
</sect2>

<sect2 id="gmmproc-m4-initializations">
<title lang="en">m4 Initializations</title>
<para lang="en">
  Often when wrapping methods, it is desirable to store the return of the C
  function in what is called an output parameter.  In this case, the C++ method
  returns <type>void</type> but an output parameter in which to store the value
  of the C function is included in the argument list of the C++ method.
  gmmproc allows such functionality, but appropriate initialization macros must
  be included to tell gmmproc how to initialize the C++ parameter from the
  return of the C function.
</para>
<para lang="en">
  For example, if there was a C function that returned a
  <type>GtkWidget*</type> and for some reason, instead of having the C++ method
  also return the widget, it was desirable to have the C++ method place the
  widget in a specified output parameter, an initialization macro such as the
  following would be necessary:
<programlisting lang="en">
_INITIALIZATION(`Gtk::Widget&amp;',`GtkWidget*',`$3 = Glib::wrap($4)')
</programlisting>
</para>

<para lang="en">
  <literal>$3</literal> will be replaced by the output parameter name of the
  C++ method and <literal>$4</literal> will be replaced by the return of the C
  function when this initialization is used by gmmproc.  For convenience,
  <literal>$1</literal> will also be replaced by the C++ type without the
  ampersand (&amp;) and <literal>$2</literal> will be replaced by the C type.
</para>
</sect2>


<sect2 id="gmmproc-class-macros">
<title>Macros de classes</title>
<para>La macro de classe déclare la classe elle-même et ses relations avec le type C sous-jacent. Elle génère certains constructeurs internes, la variable membre <varname>gobject_</varname>, des définitions de types, les mécanismes d'accès aux <function>gobj()</function>, l'enregistrement du type et la fonction membre <function>Glib::wrap()</function>, entre autres choses.</para>
<para lang="en">Other macros, such as <function>_WRAP_METHOD()</function> and
    <function>_WRAP_SIGNAL()</function> may only be used after a call to a
    <function>_CLASS_*</function> macro.</para>

<sect3 id="gmmproc-class-gobject">
<title>_CLASS_GOBJECT</title>
<para lang="en">This macro declares a wrapper for a type that is derived from
    <classname>GObject</classname>, but whose wrapper is not derived from
    <classname>Gtk::Object</classname>.</para>
<para lang="en"><function>_CLASS_GOBJECT( C++ class, C class, C casting macro, C++ base class, C base class )</function></para>
<para lang="en">For instance, from <filename>accelgroup.hg</filename>:
<programlisting lang="en">
_CLASS_GOBJECT(AccelGroup, GtkAccelGroup, GTK_ACCEL_GROUP, Glib::Object, GObject)
</programlisting>
</para>
</sect3>

<sect3 id="gmmproc-class-gtkobject">
<title>_CLASS_GTKOBJECT</title>
<para lang="en">This macro declares a wrapper for a type whose wrapper is derived from
    <classname>Gtk::Object</classname>, such as a widget or dialog.</para>
<para lang="en"><function>_CLASS_GTKOBJECT( C++ class, C class, C casting macro, C++ base class, C base class )</function></para>
<para lang="en">For instance, from <filename>button.hg</filename>:
<programlisting lang="en">
_CLASS_GTKOBJECT(Button, GtkButton, GTK_BUTTON, Gtk::Bin, GtkBin)
</programlisting>
</para>
<para lang="en">You will typically use this macro when the class already derives from Gtk::Object. For instance, you will use it when wrapping a GTK+ Widget, because Gtk::Widget derives from Gtk::Object.</para>
<para lang="en">You might also derive non-widget classes from Gtk::Object so they can be used without <classname>Glib::RefPtr</classname>. For instance, they could then be instantiated with <function>Gtk::manage()</function> or on the stack as a member variable. This is convenient, but you should use this only when you are sure that true reference-counting is not needed. We consider it useful for widgets.</para>
</sect3>

<sect3 id="gmmproc-class-boxedtype">
<title>_CLASS_BOXEDTYPE</title>
<para>Cette macro déclare un habillage pour une structure non-<classname>GObject</classname>, enregistrée avec <function>g_boxed_type_register_static()</function>.</para>
<para lang="en"><function>_CLASS_BOXEDTYPE( C++ class, C class, new function, copy function, free function )</function></para>
<para lang="en">For instance, from <classname>Gdk::RGBA</classname>:
<programlisting lang="en">
_CLASS_BOXEDTYPE(RGBA, GdkRGBA, NONE, gdk_rgba_copy, gdk_rgba_free)
</programlisting>
</para>
</sect3>

<sect3 id="gmmproc-class-boxedtype-static">
<title>_CLASS_BOXEDTYPE_STATIC</title>
<para>Cette macro déclare un habillage pour une simple structure assignable comme un <classname>GdkRectangle</classname>. Elle est semblable à <function>_CLASS_BOXEDTYPE</function>, mais la structure C n'est pas allouée dynamiquement.</para>
<para lang="en"><function>_CLASS_BOXEDTYPE_STATIC( C++ class, C class )</function></para>
<para lang="en">For instance, for <classname>Gdk::Rectangle</classname>:
<programlisting lang="en">
_CLASS_BOXEDTYPE_STATIC(Rectangle, GdkRectangle)
</programlisting>
</para>
</sect3>

<sect3 id="gmmproc-class-opaque-copyable">
<title>_CLASS_OPAQUE_COPYABLE</title>
<para>Cette macro déclare un habillage pour une structure opaque possédant des fonctions de copie et de libération. Les fonctions new, copy et free seront utilisées pour instancier le constructeur par défaut, le constructeur de copie et le destructeur.</para>
<para lang="en"><function>_CLASS_OPAQUE_COPYABLE( C++ class, C class, new function, copy function, free function )</function></para>
<para lang="en">For instance, from <classname>Glib::Checksum</classname>:
<programlisting lang="en">
_CLASS_OPAQUE_COPYABLE(Checksum, GChecksum, NONE, g_checksum_copy, g_checksum_free)
</programlisting>
</para>
</sect3>

<sect3 id="gmmproc-class-opaque-refcounted">
<title>_CLASS_OPAQUE_REFCOUNTED</title>
<para>Cette macro déclare un habillage pour une structure opaque à décompte de références. L'habillage C++ ne peut pas être directement instancié et ne peut être utilisé qu'avec un pointeur intelligent <classname>Glib::RefPtr</classname>.</para>
<para lang="en"><function>_CLASS_OPAQUE_REFCOUNTED( C++ class, C class, new function, ref function, unref function )</function></para>
<para lang="en">For instance, for <classname>Pango::Coverage</classname>:
<programlisting lang="en">
_CLASS_OPAQUE_REFCOUNTED(Coverage, PangoCoverage, pango_coverage_new, pango_coverage_ref, pango_coverage_unref)
</programlisting>
</para>
</sect3>

<sect3 id="gmmproc-class-generic">
<title>_CLASS_GENERIC</title>
<para>Cette macro peut être utilisée pour habiller les structures n'entrant pas dans une catégorie particulière.</para>
<para lang="en"><function>_CLASS_GENERIC( C++ class, C class )</function></para>
<para lang="en">For instance, for <classname>Pango::AttrIter</classname>:
<programlisting lang="en">
_CLASS_GENERIC(AttrIter, PangoAttrIterator)
</programlisting>
</para>
</sect3>

<sect3 id="gmmproc-class-interface">
<title>_CLASS_INTERFACE</title>
<para lang="en">This macro declares a wrapper for a type that is derived from
    <classname>GTypeInterface</classname>.
</para>
<para lang="en"><function>_CLASS_INTERFACE( C++ class, C class, C casting macro, C interface struct, Base C++ class (optional), Base C class (optional) )</function></para>
<para lang="en">
For instance, from <filename>celleditable.hg</filename>:
<programlisting lang="en">
_CLASS_INTERFACE(CellEditable, GtkCellEditable, GTK_CELL_EDITABLE, GtkCellEditableIface)
</programlisting>
</para>
<para lang="en">Two extra parameters are optional, for the case that the interface derives from another interface,
which should be the case when the GInterface has another GInterface as a prerequisite.
For instance, from <filename>loadableicon.hg</filename>:
<programlisting lang="en">
_CLASS_INTERFACE(LoadableIcon, GLoadableIcon, G_LOADABLE_ICON, GLoadableIconIface, Icon, GIcon)
</programlisting>
</para>
</sect3>

</sect2>

<sect2 id="gmmproc-constructor-macros">
<title>Macros de constructeurs</title>
<para>Les macros <function>_CTOR_DEFAULT()</function> et <function>_WRAP_CTOR()</function> ajoutent des constructeurs, habillant les fonctions C <function>*_new()</function> spécifiées. Ces macros supposent que l'objet C a des propriétés de même nom que les paramètres de la fonction, ce qui est habituellement le cas ; ainsi il peut fournir les paramètres directement pour l'appel de <function>g_object_new()</function>. Ces constructeurs en réalité n'appellent jamais les fonctions C <function>*_new()</function>, car gtkmm doit en fait instancier des types GTypes dérivés et les fonctions C <function>*_new()</function> ne sont conçues que comme fonctions de commodité pour les programmeurs C.</para>
<para lang="en">When using <function>_CLASS_GOBJECT()</function>, the constructors should
    be protected (rather than public) and each constructor should have a
    corresponding <function>_WRAP_CREATE()</function> in the public section.
    This prevents the class from being instantiated without using a
    <classname>RefPtr</classname>. For instance:
<programlisting lang="en">
class TextMark : public Glib::Object
{
  _CLASS_GOBJECT(TextMark, GtkTextMark, GTK_TEXT_MARK, Glib::Object, GObject)

protected:
  _WRAP_CTOR(TextMark(const Glib::ustring&amp; name, bool left_gravity = true), gtk_text_mark_new)

public:
  _WRAP_CREATE(const Glib::ustring&amp; name, bool left_gravity = true)
</programlisting>
</para>

<sect3 id="gmmproc-ctor-default">
<title>_CTOR_DEFAULT</title>
<para>Cette macro crée un constructeur par défaut sans paramètre.</para>
</sect3>

<sect3 id="gmmproc-wrap-ctor">
<title>_WRAP_CTOR</title>
<para>Cette macro crée un constructeur avec paramètres, équivalent à la fonction C <function>*_new()</function>. Elle n'appelle pas réellement la fonction <function>*_new()</function>, mais elle crée simplement un constructeur équivalent avec les mêmes types de paramètres. Elle prend en paramètres la signature d'un constructeur C++ et un nom de fonction C.</para>

<para lang="en">It also takes an optional extra argument:
  <variablelist>
    <varlistentry>
        <term lang="en">errthrow</term>
        <listitem>
          <para lang="en">This tells gmmproc that the C <function>*_new()</function> has
            a final GError** parameter which should be ignored.</para>
        </listitem>
    </varlistentry>
  </variablelist>
</para>
</sect3>

<sect3 id="gmmproc-ctor-manual">
<title>Constructeurs codés à la main</title>
<para lang="en">When a constructor must be partly hand written because, for instance, the
    <function>*_new()</function> C function's parameters do not correspond
    directly to object properties, or because the <function>*_new()</function> C
    function does more than call <function>g_object_new()</function>, the
    <function>_CONSTRUCT()</function> macro may be used in the
    .ccg file to save some work. The <function>_CONSTRUCT</function> macro takes
    a series of property names and values. For instance, from
    <filename>button.ccg</filename>:
<programlisting lang="en">
Button::Button(const Glib::ustring&amp; label, bool mnemonic)
:
  _CONSTRUCT("label", label.c_str(), "use_underline", gboolean(mnemonic))
{}
</programlisting>
</para>
</sect3>

</sect2>

<sect2 id="gmmproc-suppressing-macros">
<title lang="en">Macros that suppress generation of some code</title>
<para lang="en">Some macros suppress the generation of some code when they are used after
a <function>_CLASS_*</function> macro. Some suppress the definition in the
generated .cc file, others suppress both the declaration in the .h file and
the definition in the .cc file.
</para>

<sect3 id="gmmproc-custom-default-ctor">
<title lang="en">_CUSTOM_DEFAULT_CTOR</title>
<para lang="en">Suppresses declaration and definition of default constructor in
<function>_CLASS_BOXEDTYPE</function>, <function>_CLASS_BOXEDTYPE_STATIC</function>
and <function>_CLASS_OPAQUE_COPYABLE</function>.
</para>
</sect3>

<sect3 id="gmmproc-custom-ctor-cast">
<title lang="en">_CUSTOM_CTOR_CAST</title>
<para lang="en">Suppresses declaration and definition of the constructor that takes a pointer
to the wrapped C object in <function>_CLASS_BOXEDTYPE</function> and
<function>_CLASS_BOXEDTYPE_STATIC</function>.
</para>
<para lang="en">Suppresses definition of the constructor that takes a pointer to the
wrapped C object in <function>_CLASS_GOBJECT</function>, <function>_CLASS_GTKOBJECT</function>,
<function>_CLASS_INTERFACE</function> and <function>_CLASS_OPAQUE_COPYABLE</function>.
</para>
</sect3>

<sect3 id="gmmproc-custom-dtor">
<title lang="en">_CUSTOM_DTOR</title>
<para lang="en">Suppresses definition of destructor in
<function>_CLASS_GOBJECT</function> and <function>_CLASS_GTKOBJECT</function>.
</para>
</sect3>

<sect3 id="gmmproc-custom-move-operations">
<title lang="en">_CUSTOM_MOVE_OPERATIONS</title>
<para lang="en">Suppresses declaration and definition of move constructor and move
assignment operator in <function>_CLASS_GOBJECT</function>.
</para>
<para lang="en">For example:
<programlisting lang="en">
class Derived : public Glib::Object
{
  _CLASS_GOBJECT(Derived, GDerived, G_DERIVED, Glib::Object, GObject)

  _CUSTOM_MOVE_OPERATIONS

public:
  Derived(Derived&amp;&amp; src) noexcept;
  Derived&amp; operator=(Derived&amp;&amp; src) noexcept;
  // ...
};
</programlisting>
</para>
</sect3>

<sect3 id="gmmproc-custom-wrap-new">
<title lang="en">_CUSTOM_WRAP_NEW</title>
<para lang="en">Suppresses definition of <function>Glib::wrap_new()</function> function in
<function>_CLASS_GOBJECT</function>.
</para>
</sect3>

<sect3 id="gmmproc-custom-wrap-function">
<title lang="en">_CUSTOM_WRAP_FUNCTION</title>
<para lang="en">Suppresses definition of <function>Glib::wrap()</function> function in
<function>_CLASS_GOBJECT</function> and <function>_CLASS_GTKOBJECT</function>.
</para>
</sect3>

<sect3 id="gmmproc-no-wrap-function">
<title lang="en">_NO_WRAP_FUNCTION</title>
<para lang="en">Suppresses declaration and definition of <function>Glib::wrap()</function>
function in <function>_CLASS_GOBJECT</function>, <function>_CLASS_BOXEDTYPE</function>,
<function>_CLASS_BOXEDTYPE_STATIC</function>, <function>_CLASS_OPAQUE_COPYABLE</function>,
<function>_CLASS_INTERFACE</function> and <function>_CLASS_GTKOBJECT</function>.
</para>
</sect3>

</sect2>

<sect2 id="gmmproc-method-macros">
<title>Macros pour fonctions membres</title>

<sect3 id="gmmproc-wrap-method">
<title>_WRAP_METHOD</title>
<para>Cette macro génère une fonction membre C++ habillant une fonction C.</para>
<para lang="en"><function>_WRAP_METHOD( C++ method signature, C function name)</function></para>
<para lang="en">For instance, from <filename>entry.hg</filename>:
<programlisting lang="en">
_WRAP_METHOD(void set_text(const Glib::ustring&amp; text), gtk_entry_set_text)
</programlisting>
</para>
<para>La fonction C (par exemple, <function>gtk_entry_set_text</function>) est décrite plus précisément dans les fichiers .defs et les fichiers <filename>convert*.m4</filename> contiennent la conversion nécessaire des types de paramètres C++ vers les paramètres de type C. Cette macro génère également des commentaires pour la documentation doxygen à partir des fichiers <filename>*_docs.xml</filename> et <filename>*_docs_override.xml</filename>.</para>
<para lang="en">There are some optional extra arguments:
<variablelist>
    <varlistentry>
        <term lang="en">refreturn</term>
        <listitem>
            <para lang="en">Do an extra <function>reference()</function> on the return value,
                in case the C function does not provide a reference.</para>
        </listitem>
    </varlistentry>
    <varlistentry>
        <term lang="en">errthrow</term>
        <listitem>
            <para lang="en">Use the last GError** parameter of the C function to
                throw an exception.</para>
        </listitem>
    </varlistentry>
    <varlistentry>
        <term lang="en">deprecated ["&lt;text&gt;"]</term>
        <listitem>
            <para lang="en">Puts the generated code in #ifdef blocks. Text about the
                deprecation can be specified as an optional
                parameter.</para>
        </listitem>
    </varlistentry>
    <varlistentry>
        <term lang="en">constversion</term>
        <listitem>
            <para lang="en">Just call the non-const version of the same function,
                instead of generating almost duplicate code.</para>
        </listitem>
    </varlistentry>
    <varlistentry>
        <term lang="en">newin "&lt;version&gt;"</term>
        <listitem>
            <para lang="en">Adds a @newin Doxygen command to the documentation, or replaces
                the @newin command generated from the C documentation.</para>
        </listitem>
    </varlistentry>
    <varlistentry>
        <term lang="en">ifdef &lt;identifier&gt;</term>
        <listitem>
            <para lang="en">Puts the generated code in #ifdef blocks.</para>
        </listitem>
    </varlistentry>
    <varlistentry>
        <term lang="en">slot_name &lt;parameter_name&gt;</term>
        <listitem>
          <para lang="en">Specifies the name of the slot parameter of the method, if it
            has one.  This enables <command>gmmproc</command> to generate code
            to copy the slot and pass the copy on to the C function in its
            final <literal>gpointer user_data</literal> parameter.  The
            <literal>slot_callback</literal> option must also be used to
            specify the name of the glue callback function to also pass on to
            the C function.</para>
        </listitem>
    </varlistentry>
    <varlistentry>
        <term lang="en">slot_callback &lt;function_name&gt;</term>
        <listitem>
          <para lang="en">Used in conjunction with the <literal>slot_name</literal>
            option to specify the name of the glue callback function that
            handles extracting the slot and then calling it.  The address of
            this callback is also passed on to the C function that the method
            wraps.</para>
        </listitem>
    </varlistentry>
    <varlistentry>
        <term lang="en">no_slot_copy</term>
        <listitem>
          <para lang="en">Tells <command>gmmproc</command> not to pass a copy of the slot
            to the C function, if the method has one.  Instead the slot itself
            is passed.  The slot parameter name and the glue callback function
            must have been specified with the <literal>slot_name</literal> and
            <literal>slot_callbback</literal> options respectively.</para>
        </listitem>
    </varlistentry>
</variablelist>
</para>
<para lang="en">Selecting which C++ types should be used is also important when wrapping
  C API.  Though it's usually obvious what C++ types should be used in the C++
  method, here are some hints:
<itemizedlist>
    <listitem><para lang="en">Objects used via <classname>RefPtr</classname>: Pass the
            <classname>RefPtr</classname> as a const reference. For instance,
            <code>const Glib::RefPtr&lt;Gtk::FileFilter&gt;&amp;
                filter</code>.</para></listitem>
    <listitem><para lang="en">Const Objects used via <classname>RefPtr</classname>: If the
            object should not be changed by the function, then make sure that
            the object is const, even if the <classname>RefPtr</classname> is
            already const. For instance, <code>const Glib::RefPtr&lt;const
            Gtk::FileFilter&gt;&amp; filter</code>.</para></listitem>
<listitem><para lang="en">Wrapping <classname>GList*</classname> and
        <classname>GSList*</classname> parameters: First, you need to discover
        what objects are contained in the list's data field for each item,
        usually by reading the documentation for the C function. The list can
        then be wrapped by a <classname>std::vector</classname> type.
        For instance, <code>std::vector&lt;
        Glib::RefPtr&lt;Gdk::Pixbuf&gt; &gt;</code>.
        You may need to define a Traits type to specify how the C
        and C++ types should be converted.</para></listitem>
<listitem><para lang="en">Wrapping <classname>GList*</classname> and
        <classname>GSList*</classname> return types: You must discover whether
        the caller should free the list and whether it should release the items
        in the list, again by reading the documentation of the C function. With
        this information you can choose the ownership (none, shallow or deep)
        for the m4 conversion rule, which you should probably put directly into
        the .hg file because the ownership depends on the
        function rather than the type. For instance:
<programlisting lang="en">#m4 _CONVERSION(`GSList*',`std::vector&lt;Widget*&gt;',`Glib::SListHandler&lt;Widget*&gt;::slist_to_vector($3, Glib::OWNERSHIP_SHALLOW)')</programlisting></para></listitem>
</itemizedlist>
</para>
</sect3>

<sect3 id="gmmproc-wrap-method-docs-only">
<title>_WRAP_METHOD_DOCS_ONLY</title>
<para>Cette macro est comparable à la macro <function>_WRAP_METHOD()</function>, mais elle ne génère la documentation que dans le cas d'une fonction membre C++ habillant une fonction C. Utilisez-la si vous devez coder à la main la fonction membre, mais vous voulez utiliser la documentation qui serait générée si la fonction membre était générée.</para>
<para lang="en"><function>_WRAP_METHOD_DOCS_ONLY(C function name)</function></para>
<para lang="en">For instance, from <filename>container.hg</filename>:
<programlisting lang="en">
_WRAP_METHOD_DOCS_ONLY(gtk_container_remove)
</programlisting>
</para>
<para lang="en">There are some optional extra arguments:
<variablelist>
    <varlistentry>
        <term lang="en">errthrow</term>
        <listitem>
            <para lang="en">Excludes documentation of the last GError** parameter of
                the C function.</para>
        </listitem>
    </varlistentry>
    <varlistentry>
        <term lang="en">newin "&lt;version&gt;"</term>
        <listitem>
            <para lang="en">Adds a @newin Doxygen command to the documentation, or replaces
                the @newin command generated from the C documentation.</para>
        </listitem>
    </varlistentry>
</variablelist>
</para>
</sect3>

<sect3 id="gmmproc-ignore">
<title lang="en">_IGNORE, _IGNORE_SIGNAL, _IGNORE_PROPERTY, _IGNORE_CHILD_PROPERTY</title>
<para lang="en"><command>gmmproc</command> will warn you on stdout about functions, signals,
    properties and child properties that you have forgotten to wrap, helping to
    ensure that you are wrapping the complete API. But if you don't want to wrap
    some functions, signals, properties or child properties, or if you chose
    to hand-code some methods then you can use the _IGNORE(), _IGNORE_SIGNAL(),
    _IGNORE_PROPERTY() or _IGNORE_CHILD_PROPERTY() macro to make
    <command>gmmproc</command> stop complaining.</para>
<para>
<literallayout lang="en"><function>_IGNORE(C function name 1, C function name 2, etc)
_IGNORE_SIGNAL(C signal name 1, C signal name 2, etc)
_IGNORE_PROPERTY(C property name 1, C property name 2, etc)
_IGNORE_CHILD_PROPERTY(C child property name 1, C child property name 2, etc)</function></literallayout>
</para>
<para lang="en">For instance, from <filename>flowbox.hg</filename>:
<programlisting lang="en">
_IGNORE(gtk_flow_box_set_filter_func, gtk_flow_box_set_sort_func)
_IGNORE_SIGNAL(activate-cursor-child, toggle-cursor-child, move-cursor)
</programlisting>
</para>
</sect3>

<sect3 id="gmmproc-wrap-signal">
<title>_WRAP_SIGNAL</title>
<para>Cette macro génère le signal C++ de style libsigc++ habillant un signal C GObject. Il génère en fait un mécanisme d'accès public, comme <function>signal_clicked()</function>, qui renvoie un objet mandataire. <command>gmmproc</command> utilise le fichier .defs pour découvrir le type des paramètres du C et les fichiers de conversion .m4 pour découvrir les types de conversion appropriés.</para>
<para lang="en"><function>_WRAP_SIGNAL( C++ signal handler signature, C signal name)</function></para>
<para lang="en">For instance, from <filename>button.hg</filename>:
<programlisting lang="en">
_WRAP_SIGNAL(void clicked(),"clicked")
</programlisting>
</para>
<para lang="en">Signals usually have function pointers in the GTK struct, with a
    corresponding enum value and a <function>g_signal_new()</function> in the
    .c file.</para>
<para lang="en">There are some optional extra arguments:
<variablelist>
    <varlistentry>
        <term lang="en">no_default_handler</term>
        <listitem>
            <para lang="en">Do not generate an <function>on_something()</function> virtual
                method to allow easy overriding of the default signal handler.
                Use this when adding a signal with a default signal handler
                would break the ABI by increasing the size of the class's
                virtual function table.</para>
        </listitem>
    </varlistentry>
    <varlistentry>
        <term lang="en">custom_default_handler</term>
        <listitem>
            <para lang="en">Generate a declaration of the <function>on_something()</function>
                virtual method in the <filename>.h</filename> file, but do not
                generate a definition in the <filename>.cc</filename> file.
                Use this when you must generate the definition by hand.</para>
        </listitem>
    </varlistentry>
    <varlistentry>
        <term lang="en">custom_c_callback</term>
        <listitem>
            <para lang="en">Do not generate a C callback function for the signal.
                Use this when you must generate the callback function by hand.</para>
        </listitem>
    </varlistentry>
    <varlistentry>
        <term lang="en">refreturn</term>
        <listitem>
            <para lang="en">Do an extra <function>reference()</function> on the return value
                of the <function>on_something()</function> virtual method, in
                case the C function does not provide a reference.</para>
        </listitem>
    </varlistentry>
    <varlistentry>
        <term lang="en">deprecated ["&lt;text&gt;"]</term>
        <listitem>
            <para lang="en">Puts the generated code in #ifdef blocks. Text about the
                deprecation can be specified as an optional parameter.</para>
        </listitem>
    </varlistentry>
    <varlistentry>
        <term lang="en">newin "&lt;version&gt;"</term>
        <listitem>
            <para lang="en">Adds a @newin Doxygen command to the documentation, or replaces
                the @newin command generated from the C documentation.</para>
        </listitem>
    </varlistentry>
    <varlistentry>
        <term lang="en">ifdef &lt;identifier&gt;</term>
        <listitem>
            <para lang="en">Puts the generated code in #ifdef blocks.</para>
        </listitem>
    </varlistentry>
    <varlistentry>
        <term lang="en">exception_handler &lt;method_name&gt;</term>
	      <listitem>
	        <para lang="en">Allows to use custom exception handler instead of default one.
	            Exception might be rethrown by user-defined handler, and it will be
	            caught by default handler.</para>
	      </listitem>
    </varlistentry>
    <varlistentry>
        <term lang="en">detail_name &lt;parameter_name&gt;</term>
	      <listitem>
	        <para lang="en">Adds a <type>const Glib::ustring&amp;</type> parameter to the
	            <methodname>signal_something()</methodname> method. Use it, if the signal
	            accepts a detailed signal name, i.e. if the underlying C code registers
	            the signal with the <literal>G_SIGNAL_DETAILED</literal> flag.</para>
	      </listitem>
    </varlistentry>
    <varlistentry>
        <term lang="en">two_signal_methods</term>
	      <listitem>
	        <para lang="en">Used in conjunction with the <literal>detail_name</literal>
              option to generate two <methodname>signal_something()</methodname>
              methods, one without a parameter and one with a parameter without
              a default value. With only the <literal>detail_name</literal> option
              one method is generated, with a parameter with default value.
              Use the <literal>two_signal_methods</literal> option, if it's
              necessary in order to preserve ABI.</para>
	      </listitem>
    </varlistentry>
</variablelist>
</para>
</sect3>

<sect3 id="gmmproc-wrap-property">
<title>_WRAP_PROPERTY</title>
<para>Cette macro génère une fonction membre C++ habillant une propriété d'un GObject C. Vous devez indiquer le nom de la propriété et le type C++ souhaité pour la propriété. <command>gmmproc</command> utilise le fichier .defs pour connaître le type C et les fichiers de conversion .m4 pour découvrir les types appropriés de conversion.</para>
<para lang="en"><function>_WRAP_PROPERTY(C property name, C++ type)</function></para>
<para lang="en">For instance, from <filename>button.hg</filename>:
<programlisting lang="en">
_WRAP_PROPERTY("label", Glib::ustring)
</programlisting>
</para>
<para lang="en">There are some optional extra arguments:
<variablelist>
    <varlistentry>
        <term lang="en">deprecated ["&lt;text&gt;"]</term>
        <listitem>
            <para lang="en">Puts the generated code in #ifdef blocks. Text about the
                deprecation can be specified as an optional parameter.</para>
        </listitem>
    </varlistentry>
    <varlistentry>
        <term lang="en">newin "&lt;version&gt;"</term>
        <listitem>
            <para lang="en">Adds a @newin Doxygen command to the documentation, or replaces
                the @newin command generated from the C documentation.</para>
        </listitem>
    </varlistentry>
</variablelist>
</para>
</sect3>

<sect3 id="gmmproc-wrap-vfunc">
<title lang="en">_WRAP_VFUNC</title>
<para lang="en">This macro generates the C++ method to wrap a virtual C function.</para>
<para lang="en"><function>_WRAP_VFUNC( C++ method signature, C function name)</function></para>
<para lang="en">For instance, from <filename>widget.hg</filename>:
<programlisting lang="en">
_WRAP_VFUNC(SizeRequestMode get_request_mode() const, get_request_mode)
</programlisting>
</para>
<para lang="en">The C function (e.g. <function>get_request_mode</function>) is described
    more fully in the <filename>*_vfuncs.defs</filename> file, and the
    <filename>convert*.m4</filename> files contain the necessary conversion from
    the C++ parameter type to the C parameter type. Conversions can also be
    written in the .hg file. Virtual functions often require special conversions
    that are best kept local to the .hg file where they are used.</para>
<para lang="en">There are some optional extra arguments:
<variablelist>
    <varlistentry>
        <term lang="en">refreturn</term>
        <listitem>
            <para lang="en">Do an extra <function>reference()</function> on the return value
                of the <function>something_vfunc()</function> function,
                in case the virtual C function does not provide a reference.</para>
        </listitem>
    </varlistentry>
    <varlistentry>
        <term lang="en">refreturn_ctype</term>
        <listitem>
            <para lang="en">Do an extra <function>reference()</function> on the return value
                of an overridden <function>something_vfunc()</function> function
                in the C callback function, in case the calling C function
                expects it to provide a reference.</para>
        </listitem>
    </varlistentry>
    <varlistentry>
        <term lang="en">keep_return</term>
        <listitem>
            <para lang="en">Keep a copy of the return value in the C callback function,
                in case the calling C function does not expect to get its own
                reference.</para>
        </listitem>
    </varlistentry>
    <varlistentry>
        <term lang="en">errthrow</term>
        <listitem>
            <para lang="en">Use the last GError** parameter of the C virtual function (if
              there is one) to throw an exception.</para>
        </listitem>
    </varlistentry>
    <varlistentry>
        <term lang="en">custom_vfunc</term>
        <listitem>
            <para lang="en">Do not generate a definition of the vfunc in the
               <filename>.cc</filename> file. Use this when you must generate
               the vfunc by hand.</para>
        </listitem>
    </varlistentry>
    <varlistentry>
        <term lang="en">custom_vfunc_callback</term>
        <listitem>
            <para lang="en">Do not generate a C callback function for the vfunc.
                Use this when you must generate the callback function by hand.</para>
        </listitem>
    </varlistentry>
    <varlistentry>
        <term lang="en">ifdef &lt;identifier&gt;</term>
        <listitem>
            <para lang="en">Puts the generated code in #ifdef blocks.</para>
        </listitem>
    </varlistentry>
    <varlistentry>
        <term lang="en">slot_name &lt;parameter_name&gt;</term>
        <listitem>
          <para lang="en">Specifies the name of the slot parameter of the method, if it
            has one.  This enables <command>gmmproc</command> to generate code
            to copy the slot and pass the copy on to the C function in its
            final <literal>gpointer user_data</literal> parameter.  The
            <literal>slot_callback</literal> option must also be used to
            specify the name of the glue callback function to also pass on to
            the C function.</para>
        </listitem>
    </varlistentry>
    <varlistentry>
        <term lang="en">slot_callback &lt;function_name&gt;</term>
        <listitem>
          <para lang="en">Used in conjunction with the <literal>slot_name</literal>
            option to specify the name of the glue callback function that
            handles extracting the slot and then calling it.  The address of
            this callback is also passed on to the C function that the method
            wraps.</para>
        </listitem>
    </varlistentry>
    <varlistentry>
        <term lang="en">no_slot_copy</term>
        <listitem>
          <para lang="en">Tells <command>gmmproc</command> not to pass a copy of the slot
            to the C function, if the method has one.  Instead the slot itself
            is passed.  The slot parameter name and the glue callback function
            must have been specified with the <literal>slot_name</literal> and
            <literal>slot_callbback</literal> options respectively.</para>
        </listitem>
    </varlistentry>
    <varlistentry>
        <term lang="en">return_value &lt;value&gt;</term>
	      <listitem>
	        <para lang="en">Defines a non-default return value.</para>
	      </listitem>
    </varlistentry>
    <varlistentry>
        <term lang="en">err_return_value &lt;value&gt;</term>
	      <listitem>
	        <para lang="en">Defines a non-default return value, used only if the C++
	          <function>something_vfunc()</function> function throws an exception
	          which is propagated to the C callback function. If return_value is
	          specified, but err_return_value is not, then return_value is used
	          also when an exception is propagated.</para>
	      </listitem>
    </varlistentry>
    <varlistentry>
        <term lang="en">exception_handler &lt;method_name&gt;</term>
	      <listitem>
	        <para lang="en">Allows to use custom exception handler instead of default one.
	            Exception might be rethrown by user-defined handler, and it will be
	            caught by default handler.</para>
	      </listitem>
    </varlistentry>
</variablelist>
</para>
<para lang="en">A rule to which there may be exceptions: If the virtual C function returns
    a pointer to an object derived from <classname>GObject</classname>, i.e. a
    reference-counted object, then the virtual C++ function shall return a
    <classname>Glib::RefPtr&lt;&gt;</classname> object. One of the extra
    arguments <parameter>refreturn</parameter> or
    <parameter>refreturn_ctype</parameter> is required.</para>
</sect3>

<sect3 id="gmmproc-wrap-child-property">
<title lang="en">_WRAP_CHILD_PROPERTY</title>
<para lang="en">This macro generates the C++ method to wrap a GtkContainer child property.
    (See <ulink url="https://developer.gnome.org/gtk3/stable/GtkContainer.html">
    GtkContainer</ulink> for more information about child properties).
    Similarly to _WRAP_PROPERTY, you must specify the property name and the
    wanted C++ type for the property. <command>gmmproc</command> uses the .defs
    file to discover the C type and the .m4 convert files to discover
    appropriate type conversions.</para>
<para lang="en"><function>_WRAP_CHILD_PROPERTY(C child property name, C++ type)</function></para>
<para lang="en">For instance, from <filename>notebook.hg</filename>:
<programlisting lang="en">
_WRAP_CHILD_PROPERTY("tab-expand", bool)
</programlisting>
</para>
<para lang="en">_WRAP_CHILD_PROPERTY() accepts the same optional arguments as _WRAP_PROPERTY().
</para>
</sect3>

</sect2>

<sect2 id="gmmproc-other-macros">
<title>Autres macros :</title>
<sect3 id="gmmproc-implements-interface">
<title lang="en">_IMPLEMENTS_INTERFACE</title>
<para lang="en">This macro generates initialization code for the interface.</para>
<para lang="en"><function>_IMPLEMENTS_INTERFACE(C++ interface name)</function></para>
<para lang="en">For instance, from <filename>grid.hg</filename>:
<programlisting lang="en">
_IMPLEMENTS_INTERFACE(Orientable)
</programlisting>
</para>
<para lang="en">There is one optional extra argument:
<variablelist>
    <varlistentry>
        <term lang="en">ifdef &lt;identifier&gt;</term>
        <listitem>
            <para lang="en">Puts the generated code in #ifdef blocks.</para>
        </listitem>
    </varlistentry>
</variablelist>
</para>
</sect3>

<sect3 id="gmmproc-wrap-enum">
<title>_WRAP_ENUM</title>
<para>Cette macro génère une énumération C++ pour habiller une énumération C. Vous devez préciser le nom C++ et le nom de l'énumération C subjacente.</para>
<para lang="en">For instance, from <filename>enums.hg</filename>:
<programlisting lang="en">
_WRAP_ENUM(WindowType, GtkWindowType)
</programlisting>
</para>
<para lang="en">There are some optional extra arguments:
<variablelist>
  <varlistentry>
    <term lang="en">NO_GTYPE</term>
    <listitem>
      <para lang="en">Use this option, if the enum is not a <classname>GType</classname>.
        This is the case when there is no <function>*_get_type()</function>
        function for the C enum, but be careful that you don't just need to
        include an extra header for that function. You should also file a bug
        against the C API, because all enums should be registered as GTypes.</para>
      <para lang="en">For example, from <filename>icontheme.hg</filename>:
      <programlisting lang="en">
_WRAP_ENUM(IconLookupFlags, GtkIconLookupFlags, NO_GTYPE)
      </programlisting>
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term lang="en">s#&lt;from&gt;#&lt;to&gt;#</term>
    <listitem>
      <para lang="en">Substitutes (part of) the name of one or more enum constants.
        You can add any number of substitutions.</para>
      <para lang="en">For example, from <filename>iochannel.hg</filename> in glibmm:
      <programlisting lang="en">
_WRAP_ENUM(SeekType, GSeekType, NO_GTYPE, s#^SEEK_#SEEK_TYPE_#)
      </programlisting>
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term lang="en">deprecated ["&lt;text&gt;"]</term>
    <listitem>
      <para lang="en">Puts the generated code in #ifdef blocks. Text about the
        deprecation can be specified as an optional parameter.</para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term lang="en">newin "&lt;version&gt;"</term>
    <listitem>
      <para lang="en">Adds a @newin Doxygen command to the documentation, or replaces
        the @newin command generated from the C documentation.</para>
    </listitem>
  </varlistentry>
</variablelist>
</para>
</sect3>

<sect3 id="gmmproc-wrap-enum-docs-only">
<title lang="en">_WRAP_ENUM_DOCS_ONLY</title>
<para lang="en">This macro just generates a Doxygen documentationn block for the enum.
  This is useful for enums that can't be wrapped with
  <function>_WRAP_ENUM()</function> because they are complexly defined (maybe
  using C macros) but including the generated enum documentation is still
  desired.  It is used with the same syntax as
  <function>_WRAP_ENUM()</function> and also process the same options (though
  NO_GTYPE is just ignored because it makes no difference when just generating
  the enum's documentation).
</para>
</sect3>

<sect3 id="gmmproc-wrap-gerror">
<title>_WRAP_GERROR</title>
<para>Cette macro génère une classe d'exception C++, dérivée de Glib::Error, avec un Code enum et une fonction membre code(). Vous devez préciser le nom C++ souhaité, le nom de l'énumération correspondante C et le préfixe pour les valeurs d'énumération C.</para>
<para>Cette exception peut alors être déclenchée par des fonctions membres générées par _WRAP_METHOD() avec l'option errthrow.</para>
<para lang="en">For instance, from <filename>pixbuf.hg</filename>:
<programlisting lang="en">
_WRAP_GERROR(PixbufError, GdkPixbufError, GDK_PIXBUF_ERROR)
</programlisting>
</para>
<para lang="en">_WRAP_GERROR() accepts the same optional arguments as _WRAP_ENUM().</para>
</sect3>

<sect3 id="gmmproc-member-set-get">
    <title>_MEMBER_GET / _MEMBER_SET</title>
  <para>Si vous habillez une simple structure ou un type de boîte qui autorise un accès direct à ses données membres, utilisez ces macros pour créer les obtenteurs (get) et mutateurs (set) des données membres.</para>
  <para lang="en"><function>_MEMBER_GET(C++ name, C name, C++ type, C type)</function></para>
  <para lang="en"><function>_MEMBER_SET(C++ name, C name, C++ type, C type)</function></para>
  <para lang="en">
    For example, in <filename>rectangle.hg</filename>:
    <programlisting lang="en">_MEMBER_GET(x, x, int, int)</programlisting>
  </para>
</sect3>
<sect3 id="gmmproc-member-get-set-ptr">
  <title>_MEMBER_GET_PTR / _MEMBER_SET_PTR</title>
  <para>Utilisez ces macros pour créer automatiquement des obtenteurs (get) et des mutateurs (set) pour une donnée membre du type pointeur. Pour le mécanisme d'obtention, elle créera deux fonctions membres, une qualifiée <literal>const</literal> et une non-<literal>const</literal>.</para>
  <para lang="en"><function>_MEMBER_GET_PTR(C++ name, C name, C++ type, C type)</function></para>
  <para lang="en"><function>_MEMBER_SET_PTR(C++ name, C name, C++ type, C type)</function></para>
  <para lang="en">For example, for <classname>Pango::Analysis</classname> in <filename>item.hg</filename>:
<programlisting lang="en">
// _MEMBER_GET_PTR(engine_lang, lang_engine, EngineLang*, PangoEngineLang*)
// It's just a comment. It's difficult to find a real-world example.
</programlisting>
  </para>
</sect3>
<sect3 id="gmmproc-member-get-set-gobject">
  <title>_MEMBER_GET_GOBJECT / _MEMBER_SET_GOBJECT</title>
  <para lang="en">
    Use these macros to provide getters and setters for a data member that is a
    <classname>GObject</classname> type that must be referenced before being
    returned.
  </para>
  <para lang="en"><function>_MEMBER_GET_GOBJECT(C++ name, C name, C++ type, C type)</function></para>
  <para lang="en"><function>_MEMBER_SET_GOBJECT(C++ name, C name, C++ type, C type)</function></para>
  <para lang="en">For example, in Pangomm, <filename>layoutline.hg</filename>:
<programlisting lang="en">
_MEMBER_GET_GOBJECT(layout, layout, Pango::Layout, PangoLayout*)
</programlisting>
  </para>
</sect3>

</sect2>

<sect2 id="gmmproc-parameter-processing">
  <title lang="en">gmmproc Parameter Processing</title>
  <para lang="en"><command>gmmproc</command> allows processing the parameters in a method
    signature for the macros that process method signatures (like
    <function>_WRAP_METHOD()</function>, <function>_WRAP_CTOR()</function> and
    <function>_WRAP_CREATE()</function>) in a variety of ways:
  </para>

  <sect3 id="gmmproc-parameter-reordering">
    <title lang="en">Parameter Reordering</title>
    <para lang="en">
      For all the macros that process method signatures, it is possible to
      specify a different order for the C++ parameters than the existing order
      in the C function, virtual function or signal.  For example, say that the
      following C function were being wrapped as a C++ method for the
      <classname>Gtk::Widget</classname> class:
      <programlisting lang="en">
        void gtk_widget_set_device_events(GtkWidget* widget, GdkDevice* device,
        GdkEventMask events);
      </programlisting>
      However, changing the order of the C++ method's two parameters is
      necessary.  Something like the following would wrap the function as a C++
      method with a different order for the two parameters:
      <programlisting lang="en">
        _WRAP_METHOD(void set_device_events(Gdk::EventMask events{events},
        const Glib::RefPtr&lt;const Gdk::Device&gt;&amp; device{device}),
        gtk_widget_set_device_events)
      </programlisting>
      The <literal>{c_param_name}</literal> following the method parameter
      names tells <command>gmmproc</command> to map the C++ parameter to the
      specified C parameter within the <literal>{}</literal>.  Since the C++
      parameter names correspond to the C ones, the above could be re-written
      as:
      <programlisting lang="en">
        _WRAP_METHOD(void set_device_events(Gdk::EventMask events{.}, const
        Glib::RefPtr&lt;const Gdk::Device&gt;&amp; device{.}),
        gtk_widget_set_device_events)
      </programlisting>
    </para>
    <warning>
      <para lang="en">
        Please note that when reordering parameters for a
        <function>_WRAP_SIGNAL()</function> method signature, the C parameter
        names would always be <literal>p0</literal>, <literal>p1</literal>,
        etc. because the <filename>generate_extra_defs</filename> utility uses those
        parameter names no matter what the C API's parameter names may be.
        It's how the utility is written presently.
      </para>
    </warning>
  </sect3>

  <sect3 id="gmmproc-optional-parameter-processing">
    <title lang="en">Optional Parameter Processing</title>
    <para lang="en">
      For all macros processing method signatures except
      <function>_WRAP_SIGNAL()</function> and
      <function>_WRAP_VFUNC()</function> it is also possible to make the
      parameters optional so that extra C++ methods are generated without the
      specified optional parameter.  For example, say that the following
      <function>*_new()</function> function were being wrapped as a constructor
      in the <classname>Gtk::ToolButton</classname> class:
      <programlisting lang="en">
        GtkToolItem* gtk_tool_button_new(GtkWidget* icon_widget, const gchar*
        label);
      </programlisting>
      Also, say that the C API allowed NULL for the function's
      <parameter>label</parameter> parameter so that that parameter is optional.
      It would be possible to have <command>gmmproc</command> generate the
      original constructor (with all the parameters) along with an additional
      constructor without that optional parameter by appending a
      <literal>{?}</literal> to the parameter name like so:
      <programlisting lang="en">
        _WRAP_CTOR(ToolButton(Widget&amp; icon_widget, const Glib::ustring&amp;
        label{?}), gtk_tool_button_new)
      </programlisting>
      In this case, two constructors would be generated: One with the optional
      parameter and one without it.
    </para>
  </sect3>

  <sect3 id="gmmproc-output-parameter-processing">
    <title lang="en">Output Parameter Processing</title>
    <para lang="en">
      With <function>_WRAP_METHOD()</function> it is also possible for the
      return of the wrapped C function (if it has one) to be placed in an
      output parameter of the C++ method instead of having the C++ method also
      return a value like the C function does.  To do that, simply include the
      output parameter in the C++ method parameter list appending a
      <literal>{OUT}</literal> to the output parameter name.  For example, if
      <function>gtk_widget_get_request_mode()</function> is declared as the
      following:
      <programlisting lang="en">
        GtkSizeRequestMode gtk_widget_get_request_mode(GtkWidget* widget);
      </programlisting>
      And having the C++ method set an output parameter is desired instead of
      returning a <type>SizeRequestMode</type>, something like the following
      could be used:
      <programlisting lang="en">
        _WRAP_METHOD(void get_request_mode(SizeRequestMode&amp; mode{OUT})
        const, gtk_widget_get_request_mode)
      </programlisting>
      The <literal>{OUT}</literal> appended to the name of the
      <parameter>mode</parameter> output parameter tells
      <command>gmmproc</command> to place the return of the C function in that
      output parameter.  In this case, however, a necessary initialization
      macro like the following would also have to be specified:
      <programlisting lang="en">
        _INITIALIZATION(`SizeRequestMode&amp;',`GtkSizeRequestMode',`$3 =
        (SizeRequestMode)($4)')
      </programlisting>
      Which could also be written as:
      <programlisting lang="en">
        _INITIALIZATION(`SizeRequestMode&amp;',`GtkSizeRequestMode',`$3 =
        ($1)($4)')
      </programlisting>
    </para>
    <para lang="en">
      <function>_WRAP_METHOD()</function> also supports setting C++ output
      parameters from C output parameters if the C function being wrapped has
      any.  Suppose, for example, that we want to wrap the following C function
      that returns a value in its C output parameter
      <parameter>rect</parameter>:
      <programlisting lang="en">
        gboolean gtk_icon_view_get_cell_rect(GtkIconView* icon_view,
        GtkTreePath* path, GtkCellRenderer* cell, GdkRectangle* rect);
      </programlisting>
      To have <command>gmmproc</command> place the value returned in the C++
      <parameter>rect</parameter> output parameter, something like the
      following <function>_WRAP_METHOD()</function> directive could be used:
      <programlisting lang="en">
        _WRAP_METHOD(bool get_cell_rect(const TreeModel::Path&amp; path, const
        CellRenderer&amp; cell, Gdk::Rectangle&amp; rect{&gt;&gt;}) const,
        gtk_icon_view_get_cell_rect)
      </programlisting>
      The <literal>{&gt;&gt;}</literal> following the <parameter>rect</parameter>
      parameter name indicates that the C++ output parameter should be set from
      the value returned in the C parameter from the C function.
      <command>gmmproc</command> will generate a declaration of a temporary
      variable in which to store the value of the C output parameter and a
      statement that sets the C++ output parameter from the temporary variable.
      In this case it may be necessary to have an
      <function>_INITIALIZATION()</function> describing how to set a
      <classname>Gdk::Rectangle&amp;</classname> from a
      <classname>GdkRectangle*</classname> such as the following:
      <programlisting lang="en">
        _INITIALIZATION(`Gdk::Rectangle&amp;',`GdkRectangle', `$3 =
        Glib::wrap(&amp;($4))')
      </programlisting>
    </para>
  </sect3>

  <sect3 id="gmmproc-string-parameter-processing">
    <title lang="en">String Parameter Processing</title>
    <para lang="en">
      A string-valued input parameter in a C++ method is usually a
      <type>const Glib::ustring&amp;</type> or a <type>const std::string&amp;</type>.
      In C code it's a <type>const gchar*</type>. When an empty string is converted
      to <type>const gchar*</type>, it can be converted either to <literal>nullptr</literal>
      or to a pointer to an empty string (with <methodname>c_str()</methodname>).
      Some parameters in some C functions accept a <literal>nullptr</literal>, and
      interpret it in a special way. Other parameters must not be <literal>nullptr</literal>.
    </para>
    <para lang="en">
      The default conversion in <function>_WRAP_METHOD()</function> and similar
      directives is
      <itemizedlist>
        <listitem><para lang="en">for mandatory parameters (with or without default values):
          empty string to empty string,</para></listitem>
        <listitem><para lang="en">for optional parameters (with appended <literal>{?}</literal>):
          empty string to <literal>nullptr</literal>.</para></listitem>
      </itemizedlist>
      If the default conversion is not the best conversion, append <literal>{NULL}</literal>
      to a mandatory parameter or <literal>{?!NULL}</literal> to an optional
      parameter (<literal>!NULL</literal> = not <literal>NULL</literal>). If you
      append both a C parameter name and <literal>NULL</literal>, separate them
      with a space: <literal>{c_param_name NULL}</literal>.
    </para>
  </sect3>

</sect2>

<sect2 id="gmmproc-basic-types">
  <title>Types de base</title>
  <para>Certains types de base utilisés dans les API C possèdent une meilleure typologie en C++. Par exemple, il n'est pas nécessaire d'avoir un type <literal>gboolean</literal> puisque le C++ dispose du type <literal>bool</literal>. La liste suivante montre quelques types couramment utilisés dans les API C, types que vous pouvez convertir dans la bibliothèque d'habillage C++.</para>
  <segmentedlist><title>Équivalents des types de base</title>
    <?dbhtml list-presentation="table"?>
    <segtitle>Types C</segtitle>
    <segtitle>Types C++</segtitle>
    <seglistitem><seg lang="en"><type>gboolean</type></seg><seg lang="en"><type>bool</type></seg></seglistitem>
    <seglistitem><seg lang="en"><type>gint</type></seg><seg lang="en"><type>int</type></seg></seglistitem>
    <seglistitem><seg lang="en"><type>guint</type></seg><seg lang="en"><type>guint</type></seg></seglistitem>
    <seglistitem><seg lang="en"><type>gdouble</type></seg><seg lang="en"><type>double</type></seg></seglistitem>
    <seglistitem><seg lang="en"><type>gunichar</type></seg><seg lang="en"><type>gunichar</type></seg></seglistitem>
    <seglistitem><seg lang="en"><type>gchar*</type></seg><seg lang="en"><classname>Glib::ustring</classname> (or <classname>std::string</classname> for filenames)</seg></seglistitem>
  </segmentedlist>
</sect2>
</sect1>


<sect1 id="sec-wrapping-hand-coded-files">
<title>Fichiers sources codés à la main</title>
<para>Vous voudrez peut-être inclure des fichiers sources additionnels qui n'auraient pas été générés par <command>gmmproc</command> à partir des fichiers <filename>.hg</filename> et <filename>.ccg</filename>. Placez-les simplement dans le répertoire <filename>libsomething/libsomethingmm</filename> et mentionnez-les dans le fichier <filename>Makefile.am</filename> dans les variables <varname>files_extra_h</varname> et <varname>files_extra_cc</varname>.</para>
</sect1>

<sect1 id="sec-wrapping-initialization">
<title>Initialisation</title>
<para lang="en">Your library must be initialized before it can be used, to register the
    new types that it makes available. Also, the C library that you are wrapping
    might have its own initialization function that you should call. You can do
    this in an <function>init()</function> function that you can place in
    hand-coded <filename>init.h</filename> and <filename>init.cc</filename>
    files. This function should initialize your dependencies (such as the C
    function, and <application>gtkmm</application>) and call your generated
    <function>wrap_init()</function> function. For instance:
<programlisting lang="en">
void init()
{
  Gtk::Main::init_gtkmm_internals(); //Sets up the g type system and the Glib::wrap() table.
  wrap_init(); //Tells the Glib::wrap() table about the libsomethingmm classes.
}
</programlisting>
</para>
<para lang="en">The implementation of the <function>wrap_init()</function> method in
    <filename>wrap_init.cc</filename> is generated by
    <filename>generate_wrap_init.pl</filename>, but the declaration in
    <filename>wrap_init.h</filename> is hand-coded, so you will need to adjust
    <filename>wrap_init.h</filename> so that the <function>wrap_init()</function>
    function appears in the correct C++ namespace.</para>
</sect1>

<sect1 id="sec-wrapping-problems">
<title>Problèmes dans l'API C</title>
<para>Vous allez vraisemblablement rencontrer des problèmes dans la bibliothèque en cours d'habillage, en particulier s'il s'agit d'un nouveau projet. Voici quelques problèmes courants et leurs solutions.</para>
<sect2 id="wrapping-predeclare-structs">
<title>Impossibilité de pré-déclarer des structures</title>
<para lang="en">By convention, structs are declared in glib/GTK+-style headers like so:
<programlisting lang="en">
typedef struct _ExampleWidget ExampleWidget;

struct _ExampleWidget
{
  ...
};
</programlisting>
</para>
<para lang="en">The extra typedef allows the struct to be used in a header without including
  its full definition, simply by predeclaring it, by repeating that typedef.
  This means that you don't have to include the C library's header in your C++ header,
  thus keeping it out of your public API. <command>gmmproc</command> assumes that
  this technique was used, so you will see compiler errors if that is not the case.</para>
<para lang="en">
This compiler error might look like this:
<programlisting lang="en">
example-widget.h:56: error: using typedef-name 'ExampleWidget' after 'struct'
../../libexample/libexamplemm/example-widget.h:34: error: 'ExampleWidget' has a previous declaration here
make[4]: *** [example-widget.lo] Error 1
</programlisting>
or this:
<programlisting lang="en">
example-widget.h:60: error: '_ExampleWidget ExampleWidget' redeclared as different kind of symbol
../../libexample/libexamplemm/example-widget.h:34: error: previous declaration of 'typedef struct _ExampleWidget ExampleWidget'
</programlisting>
</para>
<para>C'est facile à corriger dans la bibliothèque C ; n'envoyez pas de correctif au mainteneur concerné.</para>
</sect2>

<sect2 id="wrapping-no-properties">
<title>Perte de propriétés</title>
<para lang="en">By convention, glib/GTK+-style objects have <function>*_new()</function>
    functions, such as <function>example_widget_new()</function> that do nothing
    more than call <function>g_object_new()</function> and return the result.
    The input parameters are supplied to <function>g_object_new()</function>
    along with the names of the properties for which they are values. For
    instance,
<programlisting lang="en">
GtkWidget* example_widget_new(int something, const char* thing)
{
        return g_object_new (EXAMPLE_TYPE_WIDGET, "something", something, "thing", thing, NULL);
}
</programlisting>
</para>
<para>Cette façon de procéder permet des liaisons de langage pour implémenter leurs propres équivalents (comme les constructeurs C++) sans utiliser les fonctions <function>*_new()</function>. Ceci est souvent nécessaire ; elles peuvent donc instancier en réalité un GType dérivé pour ajouter leurs propres accroches pour les gestionnaires de signal et les fonctions virtuelles.</para>
<para>Pour le moins, la fonction <function>_new()</function> ne doit pas utiliser une quelconque API privée (fonctions uniquement dans un fichier .c). Même s'il n'y a pas de fonctions, nous pouvons ré-implémenter 2 ou 3 lignes de code dans une fonction <function>_new()</function> pour autant que ces lignes de code utilisent une API disponible pour nous.</para>
<para lang="en">Another workaround is to add a <function>*_construct()</function> function
    that the C++ constructor can call after instantiating its own type. For
    instance,
<programlisting lang="en">
GtkWidget* example_widget_new(int something, const char* thing)
{
        ExampleWidget* widget;
        widget = g_object_new (EXAMPLE_TYPE_WIDGET, NULL);
        example_widget_construct(widget, "something", something, "thing", thing);
}

void example_widget_construct(ExampleWidget* widget, int something, const char* thing)
{
        //Do stuff that uses private API:
        widget-&gt;priv-&gt;thing = thing;
        do_something(something);
}
</programlisting>
</para>
<para>Ajouter des propriétés en s'assurant qu'elles interagissent proprement entre elles est relativement difficile à corriger dans une bibliothèque C, mais c'est possible ; faites remonter un rapport d'anomalie avec si possible un correctif au mainteneur concerné.</para>
</sect2>
</sect1>

<sect1 id="sec-wrapping-documentation">
<title>Documentation</title>
<para>En règle générale, les projets du style gtkmm utilisent Doxygen, qui lit les commentaires dans un format particulier et génère une documentation HTML. Vous pouvez écrire ces commentaires doxygen directement dans les fichiers d'en-tête.</para>

<sect2 id="wrapping-reusing-c-documentation">
<title>Réutilisation de la documentation C</title>
<para lang="en">You might wish to reuse documentation that exists for the C library that
  you are wrapping. GTK-style C libraries typically use gtk-doc and therefore
  have source code comments formatted for gtk-doc and some extra documentation
  in .sgml and .xml files. The docextract_to_xml.py script, from glibmm's
  <filename>tools/defs_gen</filename> directory, can read these files and
  generate an .xml file that <command>gmmproc</command> can use to generate
  doxygen comments. <command>gmmproc</command> will even try to transform the
  documentation to make it more appropriate for a C++ API.</para>
<para lang="en">
For instance,
<programlisting lang="en">./docextract_to_xml.py -s ~/checkout/gnome/gtk+/gtk/ &gt; gtk_docs.xml
</programlisting>
</para>
<para>Cette transformation automatique n'est pas toujours appropriée ; vous serez amené à rédiger un texte pour des fonctions membres particulières. Vous pouvez faire cela en copiant le nœud XML concernant la fonction du fichier <filename>something_docs.xml</filename> vers le fichier <filename>something_docs_override.xml</filename> et en modifiant son contenu.</para>
</sect2>

<sect2 id="wrapping-documentation-build-structure">
<title>Structure de construction de la documentation</title>
<para>Si vous avez copié l'arborescence des squelettes sources de mm-common et substitué le texte à remplacer, vous disposez déjà de fichiers <filename>Makefile.am</filename> et <filename>Doxyfile.in</filename> convenables. Avec le paramétrage de construction de mm-common, la liste des fichiers d'entrée Doxygen n'est pas définie dans le fichier de configuration Doxygen, mais passée de <command>make</command> à l'entrée standard de <command>doxygen</command>. La liste des fichiers en entrée est définie par la variable <varname>doc_input</varname> du fichier <filename>Makefile.am</filename>.</para>
</sect2>

</sect1>

</appendix>

</book>
<!-- some vim settings
    vim:ts=2 sw=2 et
-->
