slideshow.cpp Example File
slideshow/slideshow.cpp

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    #include "slideshow.h"

    #include <qmediaservice.h>
    #include <qmediaplaylist.h>
    #include <qvideowidget.h>

    #include <QtGui>

    SlideShow::SlideShow(QWidget *parent)
        : QWidget(parent)
        , imageViewer(0)
        , playlist(0)
        , statusLabel(0)
        , countdownLabel(0)
        , playButton(0)
        , stopButton(0)
        , viewerLayout(0)
    {
        imageViewer = new QMediaImageViewer(this);

        connect(imageViewer, SIGNAL(stateChanged(QMediaImageViewer::State)),
                this, SLOT(stateChanged(QMediaImageViewer::State)));
        connect(imageViewer, SIGNAL(mediaStatusChanged(QMediaImageViewer::MediaStatus)),
                this, SLOT(statusChanged(QMediaImageViewer::MediaStatus)));
        connect(imageViewer, SIGNAL(elapsedTimeChanged(int)), this, SLOT(elapsedTimeChanged(int)));

        playlist = new QMediaPlaylist;
        imageViewer->bind(playlist);

        connect(playlist, SIGNAL(loaded()), this, SLOT(playlistLoaded()));
        connect(playlist, SIGNAL(loadFailed()), this, SLOT(playlistLoadFailed()));

        connect(playlist, SIGNAL(loaded()), this, SLOT(playlistLoaded()));
        connect(playlist, SIGNAL(loadFailed()), this, SLOT(playlistLoadFailed()));

        QVideoWidget *videoWidget = new QVideoWidget;
        imageViewer->bind(videoWidget);

        statusLabel = new QLabel(tr("%1 Images").arg(0));
        statusLabel->setAlignment(Qt::AlignCenter);

        viewerLayout = new QStackedLayout;
        viewerLayout->setStackingMode(QStackedLayout::StackAll);
        viewerLayout->addWidget(videoWidget);
        viewerLayout->addWidget(statusLabel);

        statusLabel = new QLabel(tr("%1 Images").arg(0));
        statusLabel->setAlignment(Qt::AlignCenter);

        viewerLayout = new QStackedLayout;
        viewerLayout->setStackingMode(QStackedLayout::StackAll);
        viewerLayout->addWidget(videoWidget);
        viewerLayout->addWidget(statusLabel);

        QMenu *openMenu = new QMenu(this);
        openMenu->addAction(tr("Directory..."), this, SLOT(openDirectory()));
        openMenu->addAction(tr("Playlist..."), this, SLOT(openPlaylist()));

        QToolButton *openButton = new QToolButton;
        openButton->setIcon(style()->standardIcon(QStyle::SP_DialogOpenButton));
        openButton->setMenu(openMenu);
        openButton->setPopupMode(QToolButton::InstantPopup);

        playButton = new QToolButton;
        playButton->setIcon(style()->standardIcon(QStyle::SP_MediaPlay));
        playButton->setEnabled(false);

        connect(playButton, SIGNAL(clicked()), this, SLOT(play()));
        connect(this, SIGNAL(enableButtons(bool)), playButton, SLOT(setEnabled(bool)));

        stopButton = new QToolButton;
        stopButton->setIcon(style()->standardIcon(QStyle::SP_MediaStop));
        stopButton->setEnabled(false);

        connect(stopButton, SIGNAL(clicked()), imageViewer, SLOT(stop()));

        QAbstractButton *nextButton = new QToolButton;
        nextButton->setIcon(style()->standardIcon(QStyle::SP_MediaSkipForward));
        nextButton->setEnabled(false);

        connect(nextButton, SIGNAL(clicked()), playlist, SLOT(next()));
        connect(this, SIGNAL(enableButtons(bool)), nextButton, SLOT(setEnabled(bool)));

        QAbstractButton *previousButton = new QToolButton;
        previousButton->setIcon(style()->standardIcon(QStyle::SP_MediaSkipBackward));
        previousButton->setEnabled(false);

        connect(previousButton, SIGNAL(clicked()), playlist, SLOT(previous()));
        connect(this, SIGNAL(enableButtons(bool)), previousButton, SLOT(setEnabled(bool)));

        countdownLabel = new QLabel;

        QBoxLayout *controlLayout = new QHBoxLayout;
        controlLayout->setMargin(0);
        controlLayout->addWidget(openButton);
        controlLayout->addStretch(1);
        controlLayout->addWidget(previousButton);
        controlLayout->addWidget(stopButton);
        controlLayout->addWidget(playButton);
        controlLayout->addWidget(nextButton);
        controlLayout->addStretch(1);
        controlLayout->addWidget(countdownLabel);

        QBoxLayout *layout = new QVBoxLayout;
        layout->addLayout(viewerLayout);
        layout->addLayout(controlLayout);

        setLayout(layout);

    }

    void SlideShow::openPlaylist()
    {
        QString path = QFileDialog::getOpenFileName(this);

        if (!path.isEmpty()) {
            playlist->clear();
            playlist->load(QUrl::fromLocalFile(path));
        }
    }

    void SlideShow::openDirectory()
    {
        QString path = QFileDialog::getExistingDirectory(this);

        if (!path.isEmpty()) {
            playlist->clear();

            QDir dir(path);

            foreach (const QString &fileName, dir.entryList(QDir::Files))
                playlist->addMedia(QUrl::fromLocalFile(dir.absoluteFilePath(fileName)));

            statusChanged(imageViewer->mediaStatus());

            emit enableButtons(playlist->mediaCount() > 0);
        }
    }

    void SlideShow::play()
    {
        switch (imageViewer->state()) {
        case QMediaImageViewer::StoppedState:
        case QMediaImageViewer::PausedState:
            imageViewer->play();
            break;
        case QMediaImageViewer::PlayingState:
            imageViewer->pause();
            break;
        }
    }

    void SlideShow::stateChanged(QMediaImageViewer::State state)
    {
        switch (state) {
        case QMediaImageViewer::StoppedState:
            stopButton->setEnabled(false);
            playButton->setIcon(style()->standardIcon(QStyle::SP_MediaPlay));
            break;
        case QMediaImageViewer::PlayingState:
            stopButton->setEnabled(true);
            playButton->setIcon(style()->standardIcon(QStyle::SP_MediaPause));
            break;
        case QMediaImageViewer::PausedState:
            stopButton->setEnabled(true);
            playButton->setIcon(style()->standardIcon(QStyle::SP_MediaPlay));
            break;
        }
    }

    void SlideShow::statusChanged(QMediaImageViewer::MediaStatus status)
    {
        switch (status) {
        case QMediaImageViewer::NoMedia:
            statusLabel->setText(tr("%1 Images").arg(playlist->mediaCount()));
            viewerLayout->setCurrentIndex(1);
            break;
        case QMediaImageViewer::LoadingMedia:
            statusLabel->setText(tr("Image %1 of %2\nLoading...")
                    .arg(playlist->currentIndex())
                    .arg(playlist->mediaCount()));
            viewerLayout->setCurrentIndex(1);
            break;
        case QMediaImageViewer::LoadedMedia:
            statusLabel->setText(tr("Image %1 of %2")
                    .arg(playlist->currentIndex())
                    .arg(playlist->mediaCount()));
            viewerLayout->setCurrentIndex(0);
            break;
        case QMediaImageViewer::InvalidMedia:
            statusLabel->setText(tr("Image %1 of %2\nInvalid")
                    .arg(playlist->currentIndex())
                    .arg(playlist->mediaCount()));
            viewerLayout->setCurrentIndex(1);
            break;
        default:
            break;
        }
    }

    void SlideShow::playlistLoaded()
    {
        statusChanged(imageViewer->mediaStatus());

        emit enableButtons(playlist->mediaCount() > 0);
    }

    void SlideShow::playlistLoadFailed()
    {
        statusLabel->setText(playlist->errorString());
        viewerLayout->setCurrentIndex(1);

        emit enableButtons(false);
    }

    void SlideShow::elapsedTimeChanged(int time)
    {
        const int remaining = (imageViewer->timeout() - time) / 1000;

        countdownLabel->setText(tr("%1:%2")
                .arg(remaining / 60, 2, 10, QLatin1Char('0'))
                .arg(remaining % 60, 2, 10, QLatin1Char('0')));
    }