playercontrols.cpp Example File

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  #include "playercontrols.h"

  #include <QBoxLayout>
  #include <QSlider>
  #include <QStyle>
  #include <QToolButton>
  #include <QComboBox>

  PlayerControls::PlayerControls(QWidget *parent)
      : QWidget(parent)
      , playerState(QMediaPlayer::StoppedState)
      , playerMuted(false)
      , playButton(0)
      , stopButton(0)
      , nextButton(0)
      , previousButton(0)
      , muteButton(0)
      , volumeSlider(0)
      , rateBox(0)
  {
      playButton = new QToolButton(this);
      playButton->setIcon(style()->standardIcon(QStyle::SP_MediaPlay));

      connect(playButton, SIGNAL(clicked()), this, SLOT(playClicked()));

      stopButton = new QToolButton(this);
      stopButton->setIcon(style()->standardIcon(QStyle::SP_MediaStop));
      stopButton->setEnabled(false);

      connect(stopButton, SIGNAL(clicked()), this, SIGNAL(stop()));

      nextButton = new QToolButton(this);
      nextButton->setIcon(style()->standardIcon(QStyle::SP_MediaSkipForward));

      connect(nextButton, SIGNAL(clicked()), this, SIGNAL(next()));

      previousButton = new QToolButton(this);
      previousButton->setIcon(style()->standardIcon(QStyle::SP_MediaSkipBackward));

      connect(previousButton, SIGNAL(clicked()), this, SIGNAL(previous()));

      muteButton = new QToolButton(this);
      muteButton->setIcon(style()->standardIcon(QStyle::SP_MediaVolume));

      connect(muteButton, SIGNAL(clicked()), this, SLOT(muteClicked()));

      volumeSlider = new QSlider(Qt::Horizontal, this);
      volumeSlider->setRange(0, 100);

      connect(volumeSlider, SIGNAL(sliderMoved(int)), this, SIGNAL(changeVolume(int)));

      rateBox = new QComboBox(this);
      rateBox->addItem("0.5x", QVariant(0.5));
      rateBox->addItem("1.0x", QVariant(1.0));
      rateBox->addItem("2.0x", QVariant(2.0));
      rateBox->setCurrentIndex(1);

      connect(rateBox, SIGNAL(activated(int)), SLOT(updateRate()));

      QBoxLayout *layout = new QHBoxLayout;
      layout->setMargin(0);
      layout->addWidget(stopButton);
      layout->addWidget(previousButton);
      layout->addWidget(playButton);
      layout->addWidget(nextButton);
      layout->addWidget(muteButton);
      layout->addWidget(volumeSlider);
      layout->addWidget(rateBox);
      setLayout(layout);
  }

  QMediaPlayer::State PlayerControls::state() const
  {
      return playerState;
  }

  void PlayerControls::setState(QMediaPlayer::State state)
  {
      if (state != playerState) {
          playerState = state;

          switch (state) {
          case QMediaPlayer::StoppedState:
              stopButton->setEnabled(false);
              playButton->setIcon(style()->standardIcon(QStyle::SP_MediaPlay));
              break;
          case QMediaPlayer::PlayingState:
              stopButton->setEnabled(true);
              playButton->setIcon(style()->standardIcon(QStyle::SP_MediaPause));
              break;
          case QMediaPlayer::PausedState:
              stopButton->setEnabled(true);
              playButton->setIcon(style()->standardIcon(QStyle::SP_MediaPlay));
              break;
          }
      }
  }

  int PlayerControls::volume() const
  {
      return volumeSlider ? volumeSlider->value() : 0;
  }

  void PlayerControls::setVolume(int volume)
  {
      if (volumeSlider)
          volumeSlider->setValue(volume);
  }

  bool PlayerControls::isMuted() const
  {
      return playerMuted;
  }

  void PlayerControls::setMuted(bool muted)
  {
      if (muted != playerMuted) {
          playerMuted = muted;

          muteButton->setIcon(style()->standardIcon(muted
                  ? QStyle::SP_MediaVolumeMuted
                  : QStyle::SP_MediaVolume));
      }
  }

  void PlayerControls::playClicked()
  {
      switch (playerState) {
      case QMediaPlayer::StoppedState:
      case QMediaPlayer::PausedState:
          emit play();
          break;
      case QMediaPlayer::PlayingState:
          emit pause();
          break;
      }
  }

  void PlayerControls::muteClicked()
  {
      emit changeMuting(!playerMuted);
  }

  qreal PlayerControls::playbackRate() const
  {
      return rateBox->itemData(rateBox->currentIndex()).toDouble();
  }

  void PlayerControls::setPlaybackRate(float rate)
  {
      for (int i = 0; i < rateBox->count(); ++i) {
          if (qFuzzyCompare(rate, float(rateBox->itemData(i).toDouble()))) {
              rateBox->setCurrentIndex(i);
              return;
          }
      }

      rateBox->addItem(QString("%1x").arg(rate), QVariant(rate));
      rateBox->setCurrentIndex(rateBox->count() - 1);
  }

  void PlayerControls::updateRate()
  {
      emit changeRate(playbackRate());
  }