slideshow.cpp Example File

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 #include "slideshow.h"

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

 #include <QtGui>

 SlideShow::SlideShow(QWidget *parent)
     : QMainWindow(parent)
     , imageViewer(0)
     , playlist(0)
     , statusLabel(0)
     , countdownLabel(0)
     , playAction(0)
     , stopAction(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()));

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

     menuBar()->addAction(tr("Open Directory..."), this, SLOT(openDirectory()));
     menuBar()->addAction(tr("Open Playlist..."), this, SLOT(openPlaylist()));

     toolBar = new QToolBar;
     toolBar->setMovable(false);
     toolBar->setFloatable(false);
     toolBar->setEnabled(false);

     toolBar->addAction(
             style()->standardIcon(QStyle::SP_MediaSkipBackward),
             tr("Previous"),
             playlist,
             SLOT(previous()));
     stopAction = toolBar->addAction(
             style()->standardIcon(QStyle::SP_MediaStop), tr("Stop"), imageViewer, SLOT(stop()));
     playAction = toolBar->addAction(
             style()->standardIcon(QStyle::SP_MediaPlay), tr("Play"), this, SLOT(play()));
     toolBar->addAction(
             style()->standardIcon(QStyle::SP_MediaSkipForward), tr("Next"), playlist, SLOT(next()));

     addToolBar(Qt::BottomToolBarArea, toolBar);

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

     countdownLabel = new QLabel;
     countdownLabel->setAlignment(Qt::AlignRight);

     statusBar()->addPermanentWidget(statusLabel, 1);
     statusBar()->addPermanentWidget(countdownLabel);

     setCentralWidget(videoWidget);
 }

 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());

         toolBar->setEnabled(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:
         stopAction->setEnabled(false);
         playAction->setIcon(style()->standardIcon(QStyle::SP_MediaPlay));
         break;
     case QMediaImageViewer::PlayingState:
         stopAction->setEnabled(true);
         playAction->setIcon(style()->standardIcon(QStyle::SP_MediaPause));
         break;
     case QMediaImageViewer::PausedState:
         stopAction->setEnabled(true);
         playAction->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()));
         break;
     case QMediaImageViewer::LoadingMedia:
         statusLabel->setText(tr("Image %1 of %2\nLoading...")
                 .arg(playlist->currentIndex())
                 .arg(playlist->mediaCount()));
         break;
     case QMediaImageViewer::LoadedMedia:
         statusLabel->setText(tr("Image %1 of %2")
                 .arg(playlist->currentIndex())
                 .arg(playlist->mediaCount()));
         break;
     case QMediaImageViewer::InvalidMedia:
         statusLabel->setText(tr("Image %1 of %2\nInvalid")
                 .arg(playlist->currentIndex())
                 .arg(playlist->mediaCount()));
         break;
     default:
         break;
     }
 }

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

     toolBar->setEnabled(playlist->mediaCount() > 0);
 }

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

     toolBar->setEnabled(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')));
 }