- Qt 5.5
- Qt Widgets
- Movie Example
- movieplayer.cpp Example File
- Qt 5.5.1 Reference Documentation

# movieplayer.cpp Example File

widgets/movie/movieplayer.cpp

    /****************************************************************************
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    ** This file is part of the examples of the Qt Toolkit.
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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();
    }