videoplayer.cpp Example File | Qt Multimedia 5.8

Qt 5.8 | Qt Multimedia | Video Graphics Item Example | videoplayer.cpp Example File

Qt 5.8.0 Reference Documentation

# videoplayer.cpp Example File

multimediawidgets/videographicsitem/videoplayer.cpp

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      ** This file is part of the examples of the Qt Toolkit.
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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)
      {
          videoItem = new QGraphicsVideoItem;
          videoItem->setSize(QSizeF(640, 480));

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

          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));
      }