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# Code for Music Player Example

    /****************************************************************************
    **
    ** Copyright (C) 1992-2008 Trolltech ASA. All rights reserved.
    **
    ** This file is part of Qt Jambi.
    **
    ** ** This file may be used under the terms of the GNU General Public
    ** License version 2.0 as published by the Free Software Foundation
    ** and appearing in the file LICENSE.GPL included in the packaging of
    ** this file.  Please review the following information to ensure GNU
    ** General Public Licensing requirements will be met:
    ** http://www.trolltech.com/products/qt/opensource.html
    **
    ** If you are unsure which license is appropriate for your use, please
    ** review the following information:
    ** http://www.trolltech.com/products/qt/licensing.html or contact the
    ** sales department at sales@trolltech.com.

    **
    ** This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
    ** WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
    **
    ****************************************************************************/

    package com.trolltech.examples.phonon;

    import com.trolltech.qt.*;
    import com.trolltech.qt.core.*;
    import com.trolltech.qt.gui.*;
    import com.trolltech.qt.phonon.*;
    import com.trolltech.examples.*;

    import java.util.*;

    @QtJambiExample(name = "Music Player")
    public class MusicPlayer extends QMainWindow
    {

        public MusicPlayer()
        {
            audioOutput = new AudioOutput(Phonon.Category.MusicCategory);
            mediaObject = new MediaObject(this);
            metaInformationResolver = new MediaObject(this);

            Phonon.createPath(mediaObject, audioOutput);

            mediaObject.setTickInterval(1000);

            mediaObject.tick.connect(this, "tick(long)");
            mediaObject.stateChanged.connect(this, "stateChanged(Phonon$State,Phonon$State)");
            metaInformationResolver.stateChanged.
                    connect(this, "metaStateChanged(Phonon$State,Phonon$State)");
            mediaObject.currentSourceChanged.connect(this, "sourceChanged(MediaSource)");
            mediaObject.aboutToFinish.connect(this, "aboutToFinish()");

            setupActions();
            setupMenus();
            setupUi();
            timeLcd.display("00:00");
        }

        private void addFiles()
        {
            List<String> files = QFileDialog.getOpenFileNames(this,
                                tr("Select Music Files"), ".");

            if (files.isEmpty())
                return;

            int index = sources.size();
            for (String string : files) {
                MediaSource source = new MediaSource(string);

                sources.add(source);
            }
            if (!sources.isEmpty())
                metaInformationResolver.setCurrentSource(sources.get(index));
        }

        private void about()
        {
            QMessageBox.information(this, tr("About Music Player"),
                tr("The Music Player example shows how to use Phonon - the multimedia" +
                   " framework that comes with Qt - to create a simple music player."));
        }

        private void stateChanged(Phonon.State newState, Phonon.State oldState)
        {
            switch (newState) {
                case ErrorState:
                    if (mediaObject.errorType().equals(Phonon.ErrorType.FatalError)) {
                        QMessageBox.warning(this, tr("Fatal Error"),
                        mediaObject.errorString());
                    } else {
                        QMessageBox.warning(this, tr("Error"),
                        mediaObject.errorString());
                    }
                    break;
                case PlayingState:
                    playAction.setEnabled(false);
                    pauseAction.setEnabled(true);
                    stopAction.setEnabled(true);
                    break;
                case StoppedState:
                    stopAction.setEnabled(false);
                    playAction.setEnabled(true);
                    pauseAction.setEnabled(false);
                    timeLcd.display("00:00");
                    break;
                case PausedState:
                    pauseAction.setEnabled(false);
                    stopAction.setEnabled(true);
                    playAction.setEnabled(true);
                    break;
                case BufferingState:
                    break;
            }
        }

        private void tick(long time)
        {
            QTime displayTime = new QTime(0, (int) (time / 60000) % 60, (int) (time / 1000) % 60);

            timeLcd.display(displayTime.toString("mm:ss"));
        }

        private void tableClicked(int row, int column)
        {
            boolean wasPlaying = mediaObject.state().equals(Phonon.State.PlayingState);

            mediaObject.stop();
            mediaObject.clearQueue();

            mediaObject.setCurrentSource(sources.get(row));

            if (wasPlaying)
                mediaObject.play();
            else
                mediaObject.stop();
        }

        private void sourceChanged(MediaSource source)
        {
            musicTable.selectRow(sources.indexOf(source));

            timeLcd.display("00:00");
        }

        private void metaStateChanged(Phonon.State newState, Phonon.State oldState)
        {
            if (newState.equals(Phonon.State.ErrorState)) {
                QMessageBox.warning(this, tr("Error opening files"),
                    metaInformationResolver.errorString());
                while (!sources.isEmpty() &&
                       !(sources.remove(sources.size() - 1).equals(metaInformationResolver.currentSource())));
                return;
            }

            if (!newState.equals(Phonon.State.StoppedState))
                return;

            if (metaInformationResolver.currentSource().type().equals(MediaSource.Type.Invalid))
                    return;

            Map<String, List<String>> metaData = metaInformationResolver.metaData();

            String title = "";
            if (metaData.get("TITLE") != null)
                title = metaData.get("TITLE").get(0);

            if (title.equals(""))
                title = metaInformationResolver.currentSource().fileName();

            String artist = "";
            if (metaData.get("ARTIST") != null)
                artist = metaData.get("ARTIST").get(0);

            String album = "";
            if (metaData.get("ALBUM") != null)
                album = metaData.get("ALBUM").get(0);

            String year = "";
            if (metaData.get("DATE") != null)
                year = metaData.get("DATE").get(0);

            QTableWidgetItem titleItem = new QTableWidgetItem(title);
            QTableWidgetItem artistItem = new QTableWidgetItem(artist);
            QTableWidgetItem albumItem = new QTableWidgetItem(album);
            QTableWidgetItem yearItem = new QTableWidgetItem(year);

            int currentRow = musicTable.rowCount();
            musicTable.insertRow(currentRow);
            musicTable.setItem(currentRow, 0, titleItem);
            musicTable.setItem(currentRow, 1, artistItem);
            musicTable.setItem(currentRow, 2, albumItem);
            musicTable.setItem(currentRow, 3, yearItem);

            if (musicTable.selectedItems().isEmpty()) {
                musicTable.selectRow(0);
                mediaObject.setCurrentSource(metaInformationResolver.currentSource());
            }

            MediaSource source = metaInformationResolver.currentSource();
            int index = sources.indexOf(metaInformationResolver.currentSource()) + 1;
            if (sources.size() > index) {
                metaInformationResolver.setCurrentSource(sources.get(index));
            }
            else {
                musicTable.resizeColumnsToContents();
                if (musicTable.columnWidth(0) > 300)
                    musicTable.setColumnWidth(0, 300);
            }
        }

        private void aboutToFinish()
        {
            int index = sources.indexOf(mediaObject.currentSource()) + 1;
            if (sources.size() > index) {
                mediaObject.enqueue(sources.get(index));
                musicTable.selectRow(index);
            }
        }

        private void setupActions()
        {
            playAction = new QAction(new QIcon("classpath:com/trolltech/examples/images/play.png"), tr("Play"), this);
            playAction.setShortcut(tr("Crl+P"));
            playAction.setDisabled(true);
            pauseAction = new QAction(new QIcon("classpath:com/trolltech/examples/images/pause.png"), tr("Pause"), this);
            pauseAction.setShortcut(tr("Ctrl+A"));
            pauseAction.setDisabled(true);
            stopAction = new QAction(new QIcon("classpath:com/trolltech/examples/images/stop.png"), tr("Stop"), this);
            stopAction.setShortcut(tr("Ctrl+S"));
            stopAction.setDisabled(true);
            addFilesAction = new QAction(tr("Add &Files"), this);
            addFilesAction.setShortcut(tr("Ctrl+F"));
            exitAction = new QAction(tr("E&xit"), this);
            exitAction.setShortcut(tr("Ctrl+X"));
            aboutAction = new QAction(tr("A&bout"), this);
            aboutAction.setShortcut(tr("Ctrl+B"));
            aboutQtJambiAction = new QAction(tr("About &Qt Jambi"), this);
            aboutQtJambiAction.setShortcut(tr("Ctrl+Q"));
            aboutQtAction = new QAction(tr("About Q&t"), this);

            playAction.triggered.connect(mediaObject, "play()");
            pauseAction.triggered.connect(mediaObject, "pause()");
            stopAction.triggered.connect(mediaObject, "stop()");
            addFilesAction.triggered.connect(this, "addFiles()");
            exitAction.triggered.connect(this, "close()");
            aboutAction.triggered.connect(this, "about()");
            aboutQtAction.triggered.connect(QApplication.instance(), "aboutQt()");
            aboutQtJambiAction.triggered.connect(QApplication.instance(), "aboutQtJambi()");
        }

        private void setupMenus()
        {
            QMenu fileMenu = menuBar().addMenu(tr("&File"));
            fileMenu.addAction(addFilesAction);
            fileMenu.addSeparator();
            fileMenu.addAction(exitAction);

            QMenu aboutMenu = menuBar().addMenu(tr("&Help"));
            aboutMenu.addAction(aboutAction);
            aboutMenu.addAction(aboutQtJambiAction);
            aboutMenu.addAction(aboutQtAction);
        }

        private void setupUi()
        {
            QToolBar bar = new QToolBar();

            bar.addAction(playAction);
            bar.addAction(pauseAction);
            bar.addAction(stopAction);

            seekSlider = new SeekSlider(this);
            seekSlider.setMediaObject(mediaObject);

            volumeSlider = new VolumeSlider(this);
            volumeSlider.setAudioOutput(audioOutput);
            volumeSlider.setSizePolicy(QSizePolicy.Policy.Maximum, QSizePolicy.Policy.Maximum);

            QLabel volumeLabel = new QLabel();
            volumeLabel.setPixmap(new QPixmap("images/volume.png"));

            QPalette palette = new QPalette();
            palette.setBrush(QPalette.ColorRole.Light, new QBrush(QColor.darkGray));

            timeLcd = new QLCDNumber();
            timeLcd.setPalette(palette);

            List<String> headers = new Vector<String>();
            headers.add(tr("Title"));
            headers.add(tr("Artist"));
            headers.add(tr("Album"));
            headers.add(tr("Year"));

            musicTable = new QTableWidget(0, 4);
            musicTable.setHorizontalHeaderLabels(headers);
            musicTable.setSelectionMode(QAbstractItemView.SelectionMode.SingleSelection);
            musicTable.setSelectionBehavior(QAbstractItemView.SelectionBehavior.SelectRows);
            musicTable.cellPressed.connect(this, "tableClicked(int,int)");

            QHBoxLayout seekerLayout = new QHBoxLayout();
            seekerLayout.addWidget(seekSlider);
            seekerLayout.addWidget(timeLcd);

            QHBoxLayout playbackLayout = new QHBoxLayout();
            playbackLayout.addWidget(bar);
            playbackLayout.addStretch();
            playbackLayout.addWidget(volumeLabel);
            playbackLayout.addWidget(volumeSlider);

            QVBoxLayout mainLayout = new QVBoxLayout();
            mainLayout.addWidget(musicTable);
            mainLayout.addLayout(seekerLayout);
            mainLayout.addLayout(playbackLayout);

            QWidget widget = new QWidget();
            widget.setLayout(mainLayout);

            setCentralWidget(widget);
            setWindowTitle("Phonon Music Player");
            setWindowIcon(new QIcon("classpath:com/trolltech/images/qt-logo.png"));
        }

        private SeekSlider seekSlider;
        private MediaObject mediaObject;
        private MediaObject metaInformationResolver;
        private AudioOutput audioOutput;
        private VolumeSlider volumeSlider;
        private List<MediaSource> sources =
            new Vector<MediaSource>();

        private QAction playAction;
        private QAction pauseAction;
        private QAction stopAction;
        private QAction addFilesAction;
        private QAction exitAction;
        private QAction aboutAction;
        private QAction aboutQtAction;
        private QAction aboutQtJambiAction;
        private QLCDNumber timeLcd;
        private QTableWidget musicTable;

        public static void main(String args[])
        {
                QApplication.initialize(args);
                QApplication.setApplicationName("Music Player");

                new MusicPlayer().show();

                QApplication.exec();
        }
    }