Qt 4.7: mainwidget.h Example File (demos/spectrum/app/mainwidget.h)

Qt Reference Documentation

# mainwidget.h Example File

demos/spectrum/app/mainwidget.h

     /****************************************************************************
     **
     ** Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies).
     ** All rights reserved.
     ** Contact: Nokia Corporation (qt-info@nokia.com)
     **
     ** This file is part of the examples of the Qt Toolkit.
     **
     ** $QT_BEGIN_LICENSE:BSD$
     ** You may use this file under the terms of the BSD license as follows:
     **
     ** "Redistribution and use in source and binary forms, with or without
     ** modification, are permitted provided that the following conditions are
     ** met:
     **   * Redistributions of source code must retain the above copyright
     **     notice, this list of conditions and the following disclaimer.
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     **     notice, this list of conditions and the following disclaimer in
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     **     the names of its contributors may be used to endorse or promote
     **     products derived from this software without specific prior written
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     #ifndef MAINWIDGET_H
     #define MAINWIDGET_H

     #include <QWidget>
     #include <QIcon>
     #include <QtMultimedia/qaudio.h>

     class Engine;
     class FrequencySpectrum;
     class ProgressBar;
     class Spectrograph;
     class Waveform;
     class LevelMeter;
     class SettingsDialog;
     class ToneGeneratorDialog;

     QT_FORWARD_DECLARE_CLASS(QAudioFormat)
     QT_FORWARD_DECLARE_CLASS(QLabel)
     QT_FORWARD_DECLARE_CLASS(QPushButton)
     QT_FORWARD_DECLARE_CLASS(QMenu)
     QT_FORWARD_DECLARE_CLASS(QAction)

     /**
      * Main application widget, responsible for connecting the various UI
      * elements to the Engine.
      */
     class MainWidget : public QWidget {
         Q_OBJECT
     public:
         MainWidget(QWidget *parent = 0);
         ~MainWidget();

         // QObject
         void timerEvent(QTimerEvent *event);

     public slots:
         void stateChanged(QAudio::Mode mode, QAudio::State state);
         void formatChanged(const QAudioFormat &format);
         void spectrumChanged(qint64 position, qint64 length,
                              const FrequencySpectrum &spectrum);
         void infoMessage(const QString &message, int timeoutMs);
         void errorMessage(const QString &heading, const QString &detail);
         void audioPositionChanged(qint64 position);
         void bufferLengthChanged(qint64 length);

     private slots:
         void showFileDialog();
         void showSettingsDialog();
         void showToneGeneratorDialog();
         void initializeRecord();
         void updateModeMenu();
         void updateButtonStates();

     private:
         void createUi();
         void createMenus();
         void connectUi();
         void reset();

         enum Mode {
             NoMode,
             RecordMode,
             GenerateToneMode,
             LoadFileMode
         };

         void setMode(Mode mode);

     private:
         Mode                    m_mode;

         Engine*                 m_engine;

     #ifndef DISABLE_WAVEFORM
         Waveform*               m_waveform;
     #endif
         ProgressBar*            m_progressBar;
         Spectrograph*           m_spectrograph;
         LevelMeter*             m_levelMeter;

         QPushButton*            m_modeButton;
         QPushButton*            m_recordButton;
         QIcon                   m_recordIcon;
         QPushButton*            m_pauseButton;
         QIcon                   m_pauseIcon;
         QPushButton*            m_playButton;
         QIcon                   m_playIcon;
         QPushButton*            m_settingsButton;
         QIcon                   m_settingsIcon;

         QLabel*                 m_infoMessage;
         int                     m_infoMessageTimerId;

         SettingsDialog*         m_settingsDialog;
         ToneGeneratorDialog*    m_toneGeneratorDialog;

         QMenu*                  m_modeMenu;
         QAction*                m_loadFileAction;
         QAction*                m_generateToneAction;
         QAction*                m_recordAction;

     };

     #endif // MAINWIDGET_H