Qt Reference Documentation

# movieplayer.cpp Example File

widgets/movie/movieplayer.cpp

     /****************************************************************************
     **
     ** Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies).
     ** All rights reserved.
     ** Contact: Nokia Corporation (qt-info@nokia.com)
     **
     ** This file is part of the examples of the Qt Toolkit.
     **
     ** $QT_BEGIN_LICENSE:BSD$
     ** You may use this file under the terms of the BSD license as follows:
     **
     ** "Redistribution and use in source and binary forms, with or without
     ** modification, are permitted provided that the following conditions are
     ** met:
     **   * Redistributions of source code must retain the above copyright
     **     notice, this list of conditions and the following disclaimer.
     **   * Redistributions in binary form must reproduce the above copyright
     **     notice, this list of conditions and the following disclaimer in
     **     the documentation and/or other materials provided with the
     **     distribution.
     **   * Neither the name of Nokia Corporation and its Subsidiary(-ies) nor
     **     the names of its contributors may be used to endorse or promote
     **     products derived from this software without specific prior written
     **     permission.
     **
     ** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
     ** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
     ** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
     ** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
     ** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
     ** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
     ** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
     ** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
     ** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
     ** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
     ** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
     ** $QT_END_LICENSE$
     **
     ****************************************************************************/

     #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();
     }