Qt Reference Documentation

movieplayer.cpp Example File

widgets/movie/movieplayer.cpp
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 #include <QtGui>

 #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();
 }