movieplayer.cpp Example File

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  #include <QtWidgets>

  #include "movieplayer.h"

  MoviePlayer::MoviePlayer(QWidget *parent)
      : QWidget(parent)
  {
      movie = new QMovie(this);
      movie->setCacheMode(QMovie::CacheAll);

      movieLabel = new QLabel(tr("No movie loaded"));
      movieLabel->setAlignment(Qt::AlignCenter);
      movieLabel->setSizePolicy(QSizePolicy::Ignored, QSizePolicy::Ignored);
      movieLabel->setBackgroundRole(QPalette::Dark);
      movieLabel->setAutoFillBackground(true);

      currentMovieDirectory = "movies";

      createControls();
      createButtons();

      connect(movie, SIGNAL(frameChanged(int)), this, SLOT(updateFrameSlider()));
      connect(movie, SIGNAL(stateChanged(QMovie::MovieState)),
              this, SLOT(updateButtons()));
      connect(fitCheckBox, SIGNAL(clicked()), this, SLOT(fitToWindow()));
      connect(frameSlider, SIGNAL(valueChanged(int)), this, SLOT(goToFrame(int)));
      connect(speedSpinBox, SIGNAL(valueChanged(int)),
              movie, SLOT(setSpeed(int)));

      mainLayout = new QVBoxLayout;
      mainLayout->addWidget(movieLabel);
      mainLayout->addLayout(controlsLayout);
      mainLayout->addLayout(buttonsLayout);
      setLayout(mainLayout);

      updateFrameSlider();
      updateButtons();

      setWindowTitle(tr("Movie Player"));
      resize(400, 400);
  }

  void MoviePlayer::open()
  {
      QString fileName = QFileDialog::getOpenFileName(this, tr("Open a Movie"),
                                 currentMovieDirectory);
      if (!fileName.isEmpty())
          openFile(fileName);
  }

  void MoviePlayer::openFile(const QString &fileName)
  {
      currentMovieDirectory = QFileInfo(fileName).path();

      movie->stop();
      movieLabel->setMovie(movie);
      movie->setFileName(fileName);
      movie->start();

      updateFrameSlider();
      updateButtons();
  }

  void MoviePlayer::goToFrame(int frame)
  {
      movie->jumpToFrame(frame);
  }

  void MoviePlayer::fitToWindow()
  {
      movieLabel->setScaledContents(fitCheckBox->isChecked());
  }

  void MoviePlayer::updateFrameSlider()
  {
      bool hasFrames = (movie->currentFrameNumber() >= 0);

      if (hasFrames) {
          if (movie->frameCount() > 0) {
              frameSlider->setMaximum(movie->frameCount() - 1);
          } else {
              if (movie->currentFrameNumber() > frameSlider->maximum())
                  frameSlider->setMaximum(movie->currentFrameNumber());
          }
          frameSlider->setValue(movie->currentFrameNumber());
      } else {
          frameSlider->setMaximum(0);
      }
      frameLabel->setEnabled(hasFrames);
      frameSlider->setEnabled(hasFrames);
  }

  void MoviePlayer::updateButtons()
  {
      playButton->setEnabled(movie->isValid() && movie->frameCount() != 1
                             && movie->state() == QMovie::NotRunning);
      pauseButton->setEnabled(movie->state() != QMovie::NotRunning);
      pauseButton->setChecked(movie->state() == QMovie::Paused);
      stopButton->setEnabled(movie->state() != QMovie::NotRunning);
  }

  void MoviePlayer::createControls()
  {
      fitCheckBox = new QCheckBox(tr("Fit to Window"));

      frameLabel = new QLabel(tr("Current frame:"));

      frameSlider = new QSlider(Qt::Horizontal);
      frameSlider->setTickPosition(QSlider::TicksBelow);
      frameSlider->setTickInterval(10);

      speedLabel = new QLabel(tr("Speed:"));

      speedSpinBox = new QSpinBox;
      speedSpinBox->setRange(1, 9999);
      speedSpinBox->setValue(100);
      speedSpinBox->setSuffix(tr("%"));

      controlsLayout = new QGridLayout;
      controlsLayout->addWidget(fitCheckBox, 0, 0, 1, 2);
      controlsLayout->addWidget(frameLabel, 1, 0);
      controlsLayout->addWidget(frameSlider, 1, 1, 1, 2);
      controlsLayout->addWidget(speedLabel, 2, 0);
      controlsLayout->addWidget(speedSpinBox, 2, 1);
  }

  void MoviePlayer::createButtons()
  {
      QSize iconSize(36, 36);

      openButton = new QToolButton;
      openButton->setIcon(style()->standardIcon(QStyle::SP_DialogOpenButton));
      openButton->setIconSize(iconSize);
      openButton->setToolTip(tr("Open File"));
      connect(openButton, SIGNAL(clicked()), this, SLOT(open()));

      playButton = new QToolButton;
      playButton->setIcon(style()->standardIcon(QStyle::SP_MediaPlay));
      playButton->setIconSize(iconSize);
      playButton->setToolTip(tr("Play"));
      connect(playButton, SIGNAL(clicked()), movie, SLOT(start()));

      pauseButton = new QToolButton;
      pauseButton->setCheckable(true);
      pauseButton->setIcon(style()->standardIcon(QStyle::SP_MediaPause));
      pauseButton->setIconSize(iconSize);
      pauseButton->setToolTip(tr("Pause"));
      connect(pauseButton, SIGNAL(clicked(bool)), movie, SLOT(setPaused(bool)));

      stopButton = new QToolButton;
      stopButton->setIcon(style()->standardIcon(QStyle::SP_MediaStop));
      stopButton->setIconSize(iconSize);
      stopButton->setToolTip(tr("Stop"));
      connect(stopButton, SIGNAL(clicked()), movie, SLOT(stop()));

      quitButton = new QToolButton;
      quitButton->setIcon(style()->standardIcon(QStyle::SP_DialogCloseButton));
      quitButton->setIconSize(iconSize);
      quitButton->setToolTip(tr("Quit"));
      connect(quitButton, SIGNAL(clicked()), this, SLOT(close()));

      buttonsLayout = new QHBoxLayout;
      buttonsLayout->addStretch();
      buttonsLayout->addWidget(openButton);
      buttonsLayout->addWidget(playButton);
      buttonsLayout->addWidget(pauseButton);
      buttonsLayout->addWidget(stopButton);
      buttonsLayout->addWidget(quitButton);
      buttonsLayout->addStretch();
  }