audiooutput.h Example File

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 #ifndef AUDIOOUTPUT_H
 #define AUDIOOUTPUT_H

 #include <math.h>

 #include <QAudioOutput>
 #include <QByteArray>
 #include <QComboBox>
 #include <QIODevice>
 #include <QLabel>
 #include <QMainWindow>
 #include <QObject>
 #include <QPushButton>
 #include <QSlider>
 #include <QTimer>
 #include <QScopedPointer>

 class Generator : public QIODevice
 {
     Q_OBJECT

 public:
     Generator(const QAudioFormat &format, qint64 durationUs, int sampleRate);

     void start();
     void stop();

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

 private:
     void generateData(const QAudioFormat &format, qint64 durationUs, int sampleRate);

 private:
     qint64 m_pos = 0;
     QByteArray m_buffer;
 };

 class AudioTest : public QMainWindow
 {
     Q_OBJECT

 public:
     AudioTest();
     ~AudioTest();

 private:
     void initializeWindow();
     void initializeAudio(const QAudioDeviceInfo &deviceInfo);

 private:
     QTimer *m_pushTimer = nullptr;

     // Owned by layout
     QPushButton *m_modeButton = nullptr;
     QPushButton *m_suspendResumeButton = nullptr;
     QComboBox *m_deviceBox = nullptr;
     QLabel *m_volumeLabel = nullptr;
     QSlider *m_volumeSlider = nullptr;

     QScopedPointer<Generator> m_generator;
     QScopedPointer<QAudioOutput> m_audioOutput;

     bool m_pullMode = true;

 private slots:
     void toggleMode();
     void toggleSuspendResume();
     void deviceChanged(int index);
     void volumeChanged(int);
 };

 #endif // AUDIOOUTPUT_H