text: #ifndef DIALOG_H
  #define DIALOG_H
  #include <QMainWindow>
  #include<QMediaPlayer>
  #include<QDebug>
  
  namespace Ui {
  class dialog;
  }
  
  class dialog : public QMainWindow
  {
      Q_OBJECT
  
  public:
      explicit dialog(QWidget *parent = 0);
      ~dialog();
  
  private slots:
  
      void on_actionOpen_triggered();
      void on_positionChanged(qint64 position);
      void on_durationChanged(qint64 position);
      void on_horizontalSlider_sliderMoved(int position);
  
      void on_VolumeSlider_sliderMoved(int position);
  
      void on_pushButton_clicked();
  
      void on_pushButton_2_clicked();
  
      void on_pushButton_3_clicked();
  
      void on_actionExit_triggered();
  
  private:
      Ui::dialog *ui;
      QMediaPlayer* player;
  };
  
  #endif // DIALOG_H
  