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# Movies or the Story of the Animated GIF file

The Movies example displays animated GIF files using the QMovie and QLabel classes.

Main:

    /****************************************************************************
    ** $Id:  qt/main.cpp   3.0.3   edited Dec 18 19:56 $
    **
    ** Copyright (C) 1992-2000 Trolltech AS.  All rights reserved.
    **
    ** This file is part of an example program for Qt.  This example
    ** program may be used, distributed and modified without limitation.
    **
    *****************************************************************************/

    #include <qapplication.h>
    #include <qfiledialog.h>
    #include <qpushbutton.h>
    #include <qlabel.h>
    #include <qpainter.h>
    #include <qmessagebox.h>
    #include <qmovie.h>
    #include <qvbox.h>

    class MovieScreen : public QFrame {
        Q_OBJECT
        QMovie movie;
        QString filename;
        QSize sh;

    public:
        MovieScreen(const char* fname, QMovie m, QWidget* p=0, const char* name=0, WFlags f=0) :
            QFrame(p, name, f),
            sh(100,100)
        {
            setCaption(fname);
            filename = fname;
            movie = m;

            // Set a frame around the movie.
            setFrameStyle(QFrame::WinPanel|QFrame::Sunken);

            // No background needed, since we draw on the whole widget.
            movie.setBackgroundColor(backgroundColor());
            setBackgroundMode(NoBackground);

            // Get the movie to tell use when interesting things happen.
            movie.connectUpdate(this, SLOT(movieUpdated(const QRect&)));
            movie.connectResize(this, SLOT(movieResized(const QSize&)));
            movie.connectStatus(this, SLOT(movieStatus(int)));

            setSizePolicy(QSizePolicy(QSizePolicy::Expanding,QSizePolicy::Expanding));
        }

        QSize sizeHint() const
        {
            return sh;
        }

    protected:

        // Draw the contents of the QFrame - the movie and on-screen-display
        void drawContents(QPainter* p)
        {
            // Get the current movie frame.
            QPixmap pm = movie.framePixmap();

            // Get the area we have to draw in.
            QRect r = contentsRect();

            if ( !pm.isNull() ) {
                // Only rescale is we need to - it can take CPU!
                if ( r.size() != pm.size() ) {
                    QWMatrix m;
                    m.scale((double)r.width()/pm.width(),
                            (double)r.height()/pm.height());
                    pm = pm.xForm(m);
                }

                // Draw the [possibly scaled] frame.  movieUpdated() below calls
                // repaint with only the changed area, so clipping will ensure we
                // only do the minimum amount of rendering.
                //
                p->drawPixmap(r.x(), r.y(), pm);
            }

            // The on-screen display

            const char* message = 0;

            if (movie.paused()) {
                message = "PAUSED";
            } else if (movie.finished()) {
                message = "THE END";
            } else if (movie.steps() > 0) {
                message = "FF >>";
            }

            if (message) {
                // Find a good font size...
                p->setFont(QFont("Helvetica", 24));

                QFontMetrics fm = p->fontMetrics();
                if ( fm.width(message) > r.width()-10 )
                    p->setFont(QFont("Helvetica", 18));

                fm = p->fontMetrics();
                if ( fm.width(message) > r.width()-10 )
                    p->setFont(QFont("Helvetica", 14));

                fm = p->fontMetrics();
                if ( fm.width(message) > r.width()-10 )
                    p->setFont(QFont("Helvetica", 12));

                fm = p->fontMetrics();
                if ( fm.width(message) > r.width()-10 )
                    p->setFont(QFont("Helvetica", 10));

                // "Shadow" effect.
                p->setPen(black);
                p->drawText(1, 1, width()-1, height()-1, AlignCenter, message);
                p->setPen(white);
                p->drawText(0, 0, width()-1, height()-1, AlignCenter, message);
            }
        }

    public slots:
        void restart()
        {
            movie.restart();
            repaint();
        }

        void togglePause()
        {
            if ( movie.paused() )
                movie.unpause();
            else
                movie.pause();
            repaint();
        }

        void step()
        {
            movie.step();
            repaint();
        }

        void step10()
        {
            movie.step(10);
            repaint();
        }

    private slots:
        void movieUpdated(const QRect& area)
        {
            if (!isVisible())
                show();

            // The given area of the movie has changed.

            QRect r = contentsRect();

            if ( r.size() != movie.framePixmap().size() ) {
                // Need to scale - redraw whole frame.
                repaint( r );
            } else {
                // Only redraw the changed area of the frame
                repaint( area.x()+r.x(), area.y()+r.x(),
                         area.width(), area.height() );
            }
        }

        void movieResized(const QSize& size)
        {
            // The movie changed size, probably from its initial zero size.

            int fw = frameWidth();
            sh = QSize( size.width() + fw*2, size.height() + fw*2 );
            updateGeometry();
            if ( parentWidget() && parentWidget()->isHidden() )
                parentWidget()->show();
        }

        void movieStatus(int status)
        {
            // The movie has sent us a status message.

            if (status < 0) {
                QString msg;
                msg.sprintf("Could not play movie \"%s\"", (const char*)filename);
                QMessageBox::warning(this, "movies", msg);
                parentWidget()->close();
            } else if (status == QMovie::Paused || status == QMovie::EndOfMovie) {
                repaint(); // Ensure status text is displayed
            }
        }
    };

    class MoviePlayer : public QVBox {
        MovieScreen* movie;
    public:
        MoviePlayer(const char* fname, QMovie m, QWidget* p=0, const char* name=0, WFlags f=0) :
            QVBox(p,name,f)
        {
            movie = new MovieScreen(fname, m, this);
            QHBox* hb = new QHBox(this);
            QPushButton* btn;
            btn = new QPushButton("<<", hb);
            connect(btn, SIGNAL(clicked()), movie, SLOT(restart()));
            btn = new QPushButton("||", hb);
            connect(btn, SIGNAL(clicked()), movie, SLOT(togglePause()));
            btn = new QPushButton(">|", hb);
            connect(btn, SIGNAL(clicked()), movie, SLOT(step()));
            btn = new QPushButton(">>|", hb);
            connect(btn, SIGNAL(clicked()), movie, SLOT(step10()));
        }
    };

    // A QFileDialog that chooses movies.
    //
    class MovieStarter: public QFileDialog {
        Q_OBJECT
    public:
        MovieStarter(const char *dir);

    public slots:
        void startMovie(const QString& filename);
        // QDialog's method - normally closes the file dialog.
        // We want it left open, and we want Cancel to quit everything.
        void done( int r );
    };

    MovieStarter::MovieStarter(const char *dir)
        : QFileDialog(dir, "*.gif *.mng")
    {
        //behave as in getOpenFilename
        setMode( ExistingFile );
        // When a file is selected, show it as a movie.
        connect(this, SIGNAL(fileSelected(const QString&)),
                this, SLOT(startMovie(const QString&)));
    }

    void MovieStarter::startMovie(const QString& filename)
    {
        if ( filename ) // Start a new movie - have it delete when closed.
            (new MoviePlayer( filename, QMovie(filename), 0, 0,
                                   WDestructiveClose))->show();
    }

    void MovieStarter::done( int r )
    {
        if (r != Accepted)
            qApp->quit(); // end on Cancel
        setResult( r );

        // And don't hide.
    }

    int main(int argc, char **argv)
    {
        QApplication a(argc, argv);

        if (argc > 1) {
            // Commandline mode - show movies given on the command line
            //
            bool gui=TRUE;
            for (int arg=1; arg<argc; arg++) {
                if ( QString(argv[arg]) == "-i" )
                    gui = !gui;
                else if ( gui )
                    (void)new MoviePlayer(argv[arg], QMovie(argv[arg]), 0, 0,
                                          Qt::WDestructiveClose);
                else
                    (void)new MovieScreen(argv[arg], QMovie(argv[arg]), 0, 0,
                                          Qt::WDestructiveClose);
            }
            QObject::connect(qApp, SIGNAL(lastWindowClosed()), qApp, SLOT(quit()));
        } else {
            // "GUI" mode - open a chooser for movies
            //
            MovieStarter* fd = new MovieStarter(".");
            fd->show();
        }

        // Go!
        return a.exec();
    }

    #include "main.moc"

See also Examples.