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