videoplayer.cpp Example File

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 #include "videoplayer.h"
 #include "videoitem.h"

 #include <QtWidgets>
 #include <qvideosurfaceformat.h>

 #if !defined(QT_NO_OPENGL)
 # include <QtOpenGL/QGLWidget>
 #endif

 VideoPlayer::VideoPlayer(QWidget *parent, Qt::WindowFlags flags)
     : QWidget(parent, flags)
     , mediaPlayer(0, QMediaPlayer::VideoSurface)
     , videoItem(0)
     , playButton(0)
     , positionSlider(0)
 {
     videoItem = new VideoItem;

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

 #if !defined(QT_NO_OPENGL)
     graphicsView->setViewport(new QGLWidget);
 #endif

     scene->addItem(videoItem);

     QSlider *rotateSlider = new QSlider(Qt::Horizontal);
     rotateSlider->setRange(-180,  180);
     rotateSlider->setValue(0);

     connect(rotateSlider, SIGNAL(valueChanged(int)),
             this, SLOT(rotateVideo(int)));

     QAbstractButton *openButton = new QPushButton(tr("Open..."));
     connect(openButton, SIGNAL(clicked()), this, SLOT(openFile()));

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

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

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

     connect(positionSlider, SIGNAL(sliderMoved(int)),
             this, SLOT(setPosition(int)));

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

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

     setLayout(layout);

     mediaPlayer.setVideoOutput(videoItem);
     connect(&mediaPlayer, SIGNAL(stateChanged(QMediaPlayer::State)),
             this, SLOT(mediaStateChanged(QMediaPlayer::State)));
     connect(&mediaPlayer, SIGNAL(positionChanged(qint64)), this, SLOT(positionChanged(qint64)));
     connect(&mediaPlayer, SIGNAL(durationChanged(qint64)), this, SLOT(durationChanged(qint64)));
 }

 VideoPlayer::~VideoPlayer()
 {
 }

 void VideoPlayer::openFile()
 {
     QString fileName = QFileDialog::getOpenFileName(this, tr("Open Movie"),QDir::homePath());

     if (!fileName.isEmpty()) {
         mediaPlayer.setMedia(QUrl::fromLocalFile(fileName));

         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));
 }