playercontrols.cpp Example File

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 #include "playercontrols.h"

 #include <QtWidgets/qboxlayout.h>
 #include <QtWidgets/qslider.h>
 #include <QtWidgets/qstyle.h>
 #include <QtWidgets/qtoolbutton.h>
 #include <QtWidgets/qcombobox.h>

 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);
     if (volumeSlider)
         layout->addWidget(volumeSlider);

     if (rateBox)
         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());
 }