videoplayer.cpp Example File

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  #include "videoplayer.h"

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

  VideoPlayer::VideoPlayer(QWidget *parent)
      : QWidget(parent)
      , mediaPlayer(0, QMediaPlayer::VideoSurface)
      , playButton(0)
      , positionSlider(0)
      , errorLabel(0)
  {
      QVideoWidget *videoWidget = new QVideoWidget;

      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);

      errorLabel = new QLabel;
      errorLabel->setSizePolicy(QSizePolicy::Preferred, QSizePolicy::Maximum);

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

      QBoxLayout *layout = new QVBoxLayout;
      layout->addWidget(videoWidget);
      layout->addLayout(controlLayout);
      layout->addWidget(errorLabel);

      setLayout(layout);

      mediaPlayer.setVideoOutput(videoWidget);
      connect(&mediaPlayer, &QMediaPlayer::stateChanged,
              this, &VideoPlayer::mediaStateChanged);
      connect(&mediaPlayer, &QMediaPlayer::positionChanged, this, &VideoPlayer::positionChanged);
      connect(&mediaPlayer, &QMediaPlayer::durationChanged, this, &VideoPlayer::durationChanged);
      typedef void (QMediaPlayer::*ErrorSignal)(QMediaPlayer::Error);
      connect(&mediaPlayer, static_cast<ErrorSignal>(&QMediaPlayer::error),
              this, &VideoPlayer::handleError);
  }

  VideoPlayer::~VideoPlayer()
  {
  }

  void VideoPlayer::openFile()
  {
      QFileDialog fileDialog(this);
      fileDialog.setAcceptMode(QFileDialog::AcceptOpen);
      fileDialog.setWindowTitle(tr("Open Movie"));
      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)
          setUrl(fileDialog.selectedUrls().constFirst());
  }

  void VideoPlayer::setUrl(const QUrl &url)
  {
      errorLabel->setText(QString());
      setWindowFilePath(url.isLocalFile() ? url.toLocalFile() : QString());
      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::handleError()
  {
      playButton->setEnabled(false);
      const QString errorString = mediaPlayer.errorString();
      QString message = "Error: ";
      if (errorString.isEmpty())
          message += " #" + QString::number(int(mediaPlayer.error()));
      else
          message += errorString;
      errorLabel->setText(message);
  }