Qt 5.11 | Qt Widgets | Movie Example | movieplayer.cpp Example File

Qt 5.11.3 Reference Documentation

# movieplayer.cpp Example File

widgets/movie/movieplayer.cpp

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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();
      }