videoplayer.h

/*  This file is part of the KDE project
    Copyright (C) 2004-2007 Matthias Kretz <kretz@kde.org>
 
    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Lesser General Public
    License as published by the Free Software Foundation; either
    version 2.1 of the License, or (at your option) version 3, or any
    later version accepted by the membership of KDE e.V. (or its
    successor approved by the membership of KDE e.V.), Nokia Corporation 
    (or its successors, if any) and the KDE Free Qt Foundation, which shall
    act as a proxy defined in Section 6 of version 3 of the license.
 
    This library is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    Lesser General Public License for more details.
 
    You should have received a copy of the GNU Lesser General Public 
    License along with this library.  If not, see <http://www.gnu.org/licenses/>.
 
*/
 
#ifndef Phonon_VIDEOPLAYER_H
#define Phonon_VIDEOPLAYER_H
 
#include "phonon_export.h"
#include "phononnamespace.h"
#include "mediasource.h"
#include <QWidget>
 
 
#ifndef QT_NO_PHONON_VIDEOPLAYER
 
namespace Phonon
{
class VideoPlayerPrivate;
class MediaObject;
class AudioOutput;
class VideoWidget;
 
/** \class VideoPlayer videoplayer.h phonon/VideoPlayer
 * \short Playback class for simple tasks.
 *
 * With %VideoPlayer you can get results quickly and easily. You can do the standard
 * playback tasks like play, pause and stop, but also set a playback volume and
 * seek (there's no guarantee that the seek will work, though).
 *
 * Keep in mind that when the %VideoPlayer instance is deleted the playback will
 * stop.
 *
 * A play and forget code example:
 * \code
 * VideoPlayer *player = new VideoPlayer(parentWidget);
 * connect(player, SIGNAL(finished()), player, SLOT(deleteLater()));
 * player->play(url);
 * \endcode
 *
 * \ingroup Playback
 * \ingroup PhononVideo
 * \author Matthias Kretz <kretz@kde.org>
 */
class PHONON_EXPORT VideoPlayer : public QWidget
{
    Q_OBJECT
    public:
        /**
         * Constructs a new %VideoPlayer instance.
         *
         * \param category The category used for the audio output device.
         * \param parent The QObject parent.
         */
        explicit VideoPlayer(Phonon::Category category, QWidget *parent = nullptr);
 
        /**
         * Constructs a new video widget with a \p parent
         * using Phonon::VideoCategory as its category.
         *
         * \param parent The QObject parent.
         */
        VideoPlayer(QWidget *parent = nullptr);
 
        /**
         * On destruction the playback is stopped, also the audio output is
         * removed so that the desktop mixer will not show the application
         * anymore. If you need a persistent audio output don't use
         * %VideoPlayer but MediaObject, VideoPath and VideoOutput.
         */
        ~VideoPlayer() override;
 
        /**
         * Get the total time (in milliseconds) of the file currently being played.
         */
        qint64 totalTime() const;
        /**
         * Get the current time (in milliseconds) of the file currently being played.
         */
        qint64 currentTime() const;
        /**
         * This is the current volume of the output as voltage factor.
         *
         * 1.0 means 100%, 0.5 means 50% voltage/25% power, 0.0 means 0%
         */
        float volume() const;
 
        /**
         * \returns \c true if it is currently playing
         * \returns \c false if it is currently stopped or paused
         */
        bool isPlaying() const;
        /**
         * \returns \c true if it is currently paused
         * \returns \c false if it is currently playing or stopped
         */
        bool isPaused() const;
 
        /**
         * getter for the MediaObject.
         */
        MediaObject *mediaObject() const;
 
        /**
         * getter for the AudioOutput.
         */
        AudioOutput *audioOutput() const;
 
        /**
         * getter for the VideoWidget.
         */
        VideoWidget *videoWidget() const;
 
    public Q_SLOTS:
        /**
         * Starts preloading the media data and fill audiobuffers in the
         * backend.
         *
         * When there's already a media playing (or paused) it will be stopped
         * (the finished signal will not be emitted).
         */
        void load(const Phonon::MediaSource &source);
 
        /**
         * Play the media at the given URL. Starts playback as fast as possible.
         * This can take a considerable time depending on the URL and the
         * backend.
         *
         * If you need low latency between calling play() and the sound actually
         * starting to play on your output device you need to use MediaObject
         * and be able to set the URL before calling play(). Note that
         * \code
         * audioPlayer->load(url);
         * audioPlayer->play();
         * \endcode
         * doesn't make a difference: the application should be idle between the
         * load and play calls so that the backend can start preloading the
         * media and fill audio buffers.
         */
        void play(const Phonon::MediaSource &source);
 
        /**
         * Continues playback of a paused media. Restarts playback of a stopped
         * media.
         */
        void play();
        /**
         * Pauses the playback.
         */
        void pause();
        /**
         * Stops the playback.
         */
        void stop();
 
        /**
         * Seeks to the requested time. Note that the backend is free to ignore
         * the seek request if the media source isn't seekable.
         *
         * \param ms Time in milliseconds from the start of the media.
         */
        void seek(qint64 ms);
        /**
         * Sets the volume of the output as voltage factor.
         *
         * 1.0 means 100%, 0.5 means 50% voltage/25% power, 0.0 means 0%
         */
        void setVolume(float volume);
 
    Q_SIGNALS:
        /**
         * This signal is emitted when the playback finished.
         */
        void finished();
 
    protected:
        bool event(QEvent *) override;
        VideoPlayerPrivate *const d;
};
 
} //namespace Phonon
 
#endif //QT_NO_PHONON_VIDEOPLAYER
 
 
#endif // Phonon_VIDEOPLAYER_H
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