videoplayer.cpp Example File

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  #include "videoplayer.h"

  #include <QtWidgets>
  #include <QVideoSurfaceFormat>
  #include <QGraphicsVideoItem>

  VideoPlayer::VideoPlayer(QWidget *parent)
      : QWidget(parent)
      , mediaPlayer(0, QMediaPlayer::VideoSurface)
      , videoItem(0)
      , playButton(0)
      , positionSlider(0)
  {
      const QRect screenGeometry = QApplication::desktop()->screenGeometry(this);
      videoItem = new QGraphicsVideoItem;
      videoItem->setSize(QSizeF(screenGeometry.width() / 3, screenGeometry.height() / 2));

      QGraphicsScene *scene = new QGraphicsScene(this);
      QGraphicsView *graphicsView = new QGraphicsView(scene);

      scene->addItem(videoItem);

      QSlider *rotateSlider = new QSlider(Qt::Horizontal);
      rotateSlider->setToolTip(tr("Rotate Video"));
      rotateSlider->setRange(-180,  180);
      rotateSlider->setValue(0);

      connect(rotateSlider, &QAbstractSlider::valueChanged,
              this, &VideoPlayer::rotateVideo);

      QAbstractButton *openButton = new QPushButton(tr("Open..."));
      connect(openButton, &QAbstractButton::clicked, this, &VideoPlayer::openFile);

      playButton = new QPushButton;
      playButton->setEnabled(false);
      playButton->setIcon(style()->standardIcon(QStyle::SP_MediaPlay));

      connect(playButton, &QAbstractButton::clicked, this, &VideoPlayer::play);

      positionSlider = new QSlider(Qt::Horizontal);
      positionSlider->setRange(0, 0);

      connect(positionSlider, &QAbstractSlider::sliderMoved,
              this, &VideoPlayer::setPosition);

      QBoxLayout *controlLayout = new QHBoxLayout;
      controlLayout->setMargin(0);
      controlLayout->addWidget(openButton);
      controlLayout->addWidget(playButton);
      controlLayout->addWidget(positionSlider);

      QBoxLayout *layout = new QVBoxLayout(this);
      layout->addWidget(graphicsView);
      layout->addWidget(rotateSlider);
      layout->addLayout(controlLayout);

      mediaPlayer.setVideoOutput(videoItem);
      connect(&mediaPlayer, &QMediaPlayer::stateChanged,
              this, &VideoPlayer::mediaStateChanged);
      connect(&mediaPlayer, &QMediaPlayer::positionChanged, this, &VideoPlayer::positionChanged);
      connect(&mediaPlayer, &QMediaPlayer::durationChanged, this, &VideoPlayer::durationChanged);
  }

  VideoPlayer::~VideoPlayer()
  {
  }

  QSize VideoPlayer::sizeHint() const
  {
      return (videoItem->size() * qreal(3) / qreal(2)).toSize();
  }

  bool VideoPlayer::isPlayerAvailable() const
  {
      return mediaPlayer.isAvailable();
  }

  void VideoPlayer::openFile()
  {
      QFileDialog fileDialog(this);
      fileDialog.setAcceptMode(QFileDialog::AcceptOpen);
      fileDialog.setWindowTitle(tr("Open Movie"));
      const QStringList supportedMimeTypes = mediaPlayer.supportedMimeTypes();
      if (!supportedMimeTypes.isEmpty())
          fileDialog.setMimeTypeFilters(supportedMimeTypes);
      fileDialog.setDirectory(QStandardPaths::standardLocations(QStandardPaths::MoviesLocation).value(0, QDir::homePath()));
      if (fileDialog.exec() == QDialog::Accepted)
          load(fileDialog.selectedUrls().constFirst());
  }

  void VideoPlayer::load(const QUrl &url)
  {
      mediaPlayer.setMedia(url);
      playButton->setEnabled(true);
  }

  void VideoPlayer::play()
  {
      switch(mediaPlayer.state()) {
      case QMediaPlayer::PlayingState:
          mediaPlayer.pause();
          break;
      default:
          mediaPlayer.play();
          break;
      }
  }

  void VideoPlayer::mediaStateChanged(QMediaPlayer::State state)
  {
      switch(state) {
      case QMediaPlayer::PlayingState:
          playButton->setIcon(style()->standardIcon(QStyle::SP_MediaPause));
          break;
      default:
          playButton->setIcon(style()->standardIcon(QStyle::SP_MediaPlay));
          break;
      }
  }

  void VideoPlayer::positionChanged(qint64 position)
  {
      positionSlider->setValue(position);
  }

  void VideoPlayer::durationChanged(qint64 duration)
  {
      positionSlider->setRange(0, duration);
  }

  void VideoPlayer::setPosition(int position)
  {
      mediaPlayer.setPosition(position);
  }

  void VideoPlayer::rotateVideo(int angle)
  {
      //rotate around the center of video element
      qreal x = videoItem->boundingRect().width() / 2.0;
      qreal y = videoItem->boundingRect().height() / 2.0;
      videoItem->setTransform(QTransform().translate(x, y).rotate(angle).translate(-x, -y));
  }