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# audioinput.h Example File

multimedia/audioinput/audioinput.h

     /****************************************************************************
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     ** Copyright (C) 2015 The Qt Company Ltd.
     ** Contact: http://www.qt.io/licensing/
     **
     ** This file is part of the examples of the Qt Toolkit.
     **
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     #ifndef AUDIOINPUT_H
     #define AUDIOINPUT_H

     #include <QPixmap>
     #include <QWidget>
     #include <QObject>
     #include <QMainWindow>
     #include <QPushButton>
     #include <QComboBox>
     #include <QByteArray>

     #include <qaudioinput.h>

     class AudioInfo : public QIODevice
     {
         Q_OBJECT
     public:
         AudioInfo(const QAudioFormat &format, QObject *parent);
         ~AudioInfo();

         void start();
         void stop();

         qreal level() const { return m_level; }

         qint64 readData(char *data, qint64 maxlen);
         qint64 writeData(const char *data, qint64 len);

     private:
         const QAudioFormat m_format;
         quint16 m_maxAmplitude;
         qreal m_level; // 0.0 <= m_level <= 1.0

     signals:
         void update();
     };

     class RenderArea : public QWidget
     {
         Q_OBJECT

     public:
         RenderArea(QWidget *parent = 0);

         void setLevel(qreal value);

     protected:
         void paintEvent(QPaintEvent *event);

     private:
         qreal m_level;
         QPixmap m_pixmap;
     };

     class InputTest : public QMainWindow
     {
         Q_OBJECT
     public:
         InputTest();
         ~InputTest();

     private:
         void initializeWindow();
         void initializeAudio();
         void createAudioInput();

     private slots:
         void refreshDisplay();
         void notified();
         void readMore();
         void toggleMode();
         void toggleSuspend();
         void stateChanged(QAudio::State state);
         void deviceChanged(int index);

     private:
         // Owned by layout
         RenderArea *m_canvas;
         QPushButton *m_modeButton;
         QPushButton *m_suspendResumeButton;
         QComboBox *m_deviceBox;

         QAudioDeviceInfo m_device;
         AudioInfo *m_audioInfo;
         QAudioFormat m_format;
         QAudioInput *m_audioInput;
         QIODevice *m_input;
         bool m_pullMode;
         QByteArray m_buffer;

         static const QString PushModeLabel;
         static const QString PullModeLabel;
         static const QString SuspendLabel;
         static const QString ResumeLabel;
     };

     #endif