Qt 5.9 | Qt Multimedia | Spectrum Example | mainwidget.h Example File

Qt 5.9.4 Reference Documentation

# mainwidget.h Example File

multimedia/spectrum/app/mainwidget.h

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      #ifndef MAINWIDGET_H
      #define MAINWIDGET_H

      #include <QAudio>
      #include <QIcon>
      #include <QWidget>

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

      class QAction;
      class QAudioFormat;
      class QLabel;
      class QMenu;
      class QPushButton;

      /**
       * Main application widget, responsible for connecting the various UI
       * elements to the Engine.
       */
      class MainWidget : public QWidget
      {
          Q_OBJECT

      public:
          explicit MainWidget(QWidget *parent = 0);
          ~MainWidget();

          // QObject
          void timerEvent(QTimerEvent *event) override;

      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