radiobutton(n)               Tk Built-In Commands               radiobutton(n)



NAME
       radiobutton - Create and manipulate radiobutton widgets

SYNOPSIS
       (radiobutton widget-name ?options?-
       :activebackground   :cursor   :highlightthickness :takefocus
       :activeforeground   :disabledforeground :image    :text
       :anchor   :font     :justify  :textvariable
       :background    :foreground    :padx     :underline
       :bitmap   :highlightbackground     :pady     :wraplength
       :borderwidth   :highlightcolor     :relief

WIDGET-SPECIFIC OPTIONS
       [:command command] Specifies a STk procedure to associate with the
       button.  This procedure is typically invoked when mouse button 1 is
       released over the button window.  The button's global variable
       (:variable option) will be updated before the procedure is invoked.
       [:height height] Specifies a desired height for the button.  If an
       image or bitmap is being displayed in the button then the value is in
       screen units (i.e. any of the forms acceptable to Tk_GetPixels); for
       text it is in lines of text.  If this option isn't specified, the
       button's desired height is computed from the size of the image or
       bitmap or text being displayed in it.  [:indicatoron indicatorOn]
       Specifies whether or not the indicator should be drawn.  Must be a
       proper boolean value.  If false, the relief option is ignored and the
       widget's relief is always sunken if the widget is selected and raised
       otherwise.  [:selectcolor selectColor] Specifies a background color to
       use when the button is selected.  If indicatorOn is true, the color
       applicies to the indicator.  If indicatorOn is false, this color is
       used as the background for the entire widget, in place of background or
       activeBackground, whenever the widget is selected.  If specified as an
       empty string, no special color is used for displaying when the widget
       is selected.  [:selectimage selectImage] Specifies an image to display
       (in place of the image option) when the radiobutton is selected.  This
       option is ignored unless the image option has been specified.
       [:state state] Specifies one of three states for the radiobutton:
       normal, active, or disabled.  In normal state the radiobutton is
       displayed using the foreground and background options.  The active
       state is typically used when the pointer is over the radiobutton.  In
       active state the radiobutton is displayed using the activeForeground
       and activeBackground options.  Disabled state means that the
       radiobutton should be insensitive:  the default bindings will refuse to
       activate the widget and will ignore mouse button presses.  In this
       state the disabledForeground and background options determine how the
       radiobutton is displayed.  [:stringvalue stringvalue] Specifies if the
       value set to variable by :value must be stringified. Default value for
       this option is #t.  See checkbutton for a similar example.
       [:value value] Specifies value to store in the button's associated
       variable whenever this button is selected.  [:variable variable]
       Specifies name of global variable to set whenever this button is
       selected.  Changes in this variable also cause the button to select or
       deselect itself.  Defaults to the value *selected-button*.
       [:width width] Specifies a desired width for the button.  If an image
       or bitmap is being displayed in the button, the value is in screen
       units (i.e. any of the forms acceptable to Tk_GetPixels); for text it
       is in characters.  If this option isn't specified, the button's desired
       width is computed from the size of the image or bitmap or text being
       displayed in it.


DESCRIPTION
       The radiobutton procedure creates a new window (given by the
       widget-name argument) and makes it into a radiobutton widget.
       Additional options, described above, may be specified on the procedure
       line or in the option database to configure aspects of the radiobutton
       such as its colors, font, text, and initial relief.  The radiobutton
       procedure returns its widget-name argument.  At the time this procedure
       is invoked, there must not exist a window named widget-name, but
       widget-name's parent must exist.

       A radiobutton is a widget that displays a textual string, bitmap or
       image and a diamond called an indicator.  If text is displayed, it must
       all be in a single font, but it can occupy multiple lines on the screen
       (if it contains newlines or if wrapping occurs because of the
       wrapLength option) and one of the characters may optionally be
       underlined using the underline option.  A radiobutton has all of the
       behavior of a simple button: it can display itself in either of three
       different ways, according to the state option; it can be made to appear
       raised, sunken, or flat; it can be made to flash; and it invokes a STk
       procedure whenever mouse button 1 is clicked over the check button.

       In addition, radiobuttons can be selected.  If a radiobutton is
       selected, the indicator is normally drawn with a sunken relief and a
       special color, and a STk variable associated with the radiobutton is
       set to a particular value.  If the radiobutton is not selected, the
       indicator is drawn with a raised relief and no special color.
       Typically, several radiobuttons share a single variable and the value
       of the variable indicates which radiobutton is to be selected.  When a
       radiobutton is selected it sets the value of the variable to indicate
       that fact;  each radiobutton also monitors the value of the variable
       and automatically selects and deselects itself when the variable's
       value changes.  By default the variable *selected-button* is used;  its
       contents give the name of the button that is selected, or the empty
       string if no button associated with that variable is selected.  The
       name of the variable for a radiobutton, plus the variable to be stored
       into it, may be modified with options on the procedure line or in the
       option database.  Configuration options may also be used to modify the
       way the indicator is displayed (or whether it is displayed at all).  By
       default a radio button is configured to select itself on button clicks.


WIDGET PROCEDURE
       The radiobutton procedure creates a new STk procedure whose name is
       widget-name.  This procedure may be used to invoke various operations
       on the widget.  It has the following general form: (widget-name option
       ?arg arg ...?)  Option and the args determine the exact behavior of the
       procedure.  The following procedures are possible for radiobutton
       widgets:

       (widget-name 'cget option)
              Returns the current value of the configuration option given by
              option.  Option may have any of the values accepted by the
              radiobutton procedure.

       (widget-name 'configure ?option? ?value option value ...?)
              Query or modify the configuration options of the widget.  If no
              option is specified, returns a list describing all of the
              available options for widget-name (see Tk_ConfigureInfo for
              information on the format of this list).  If option is specified
              with no value, the procedure returns a list describing the one
              named option (this list will be identical to the corresponding
              sublist of the value returned if no option is specified).  If
              one or more option-value pairs are specified, the procedure
              modifies the given widget option(s) to have the given value(s);
              in this case the procedure returns an empty string.  Option may
              have any of the values accepted by the radiobutton procedure.

       (widget-name 'deselect)
              Deselects the radiobutton and sets the associated variable to an
              empty string.  If this radiobutton was not currently selected,
              the procedure has no effect.

       (widget-name 'flash)
              Flashes the radiobutton.  This is accomplished by redisplaying
              the radiobutton several times, alternating between active and
              normal colors.  At the end of the flash the radiobutton is left
              in the same normal/active state as when the procedure was
              invoked.  This procedure is ignored if the radiobutton's state
              is disabled.

       (widget-name 'invoke)
              Does just what would have happened if the user invoked the
              radiobutton with the mouse: selects the button and invokes its
              associated STk procedure, if there is one (return value is
              undifined)..  This procedure is ignored if the radiobutton's
              state is disabled.

       (widget-name 'select)
              Selects the radiobutton and sets the associated variable to the
              value corresponding to this widget.


BINDINGS
       Tk automatically creates class bindings for radiobuttons that give them
       the following default behavior:

       [1]    The radiobutton activates whenever the mouse passes over it and
              deactivates whenever the mouse leaves the radiobutton.

       [2]    When mouse button 1 is pressed over a radiobutton it is invoked
              (it becomes selected and the procedure associated with the
              button is invoked, if there is one).

       [3]    When a radiobutton has the input focus, the space key causes the
              radiobutton to be invoked.

       If the radiobutton's state is disabled then none of the above actions
       occur:  the radiobutton is completely non-responsive.

       The behavior of radiobuttons can be changed by defining new bindings
       for individual widgets or by redefining the class bindings.


SEE ALSO
       button, checkbutton



STk                                   3.1                       radiobutton(n)
