Phonon: Difference between revisions

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    These tutorials are now under construction, please be patient.
    {{Review|Port to KF5}}
    This document has born the 28th of February 2007.
    In order to make the revision process clear, I introduce a confident index, 0 means that nobody except me had reviews the text. I please the reviewers to increment the counter to prove the validity of the tutorials.


    If you are a Phonon developer and you realize errors, you're missing some details or a whole chapter. Please feel free to complete the followings.
    {{Improve}}


    ----
    = Introduction =
    By getting involved with Phonon, you can choose between three different main tasks.
    * '''Using the Phonon API''', which allows you to develop your own multimedia application. '''This is discussed here.'''
    * '''Hacking the Phonon library'''.
    * '''Writing Phonon backend''', this consists in writing interfaces that allows Phonon to use different sound/video engine. This usually requires good skills and knowledge of the engine you interface with.


    =Introduction=
    =Abstract=
    ''Confident Index =0''
    The following example lets you select a music file and plays it. To change the sound device that is used by default, use the command <tt>systemsettings</tt>.


    The following is based on the documentation available here.
    =The Code=
    [http://www.englishbreakfastnetwork.org/apidocs/apidox-kde-4.0/kdelibs-apidocs/phonon/html/index.html Phonon API].
    All the code we need will be in one file, <tt>main.cpp</tt>. Create that file with the code below:
    <syntaxhighlight lang="cpp-qt">
    #include <phonon/mediaobject.h>
    #include <phonon/audiooutput.h>


    Getting involved with Phonon consists in three different main tasks.
    #include <QFileDialog>
    * '''Using the Phonon API''', which allows you to develop your own multimedia application.
    #include <QtGui/QApplication>
    #include <QtGui/QMainWindow>
    #include <QUrl>


    * '''Hacking the Phonon library''', (try to develop more this topic).
    class MainWindow : public QMainWindow
    {
        Q_OBJECT
        public:
            MainWindow();
    };


    * '''Writing Phonon backend''', this consists in writing interfaces that allows Phonon to use different sound/video engine. This usually requires good skills and knowledge of the engine you interface.
    MainWindow::MainWindow()
    {
        Phonon::MediaObject* media = new Phonon::MediaObject(this);
        Phonon::createPath(media, new Phonon::AudioOutput(Phonon::MusicCategory, this));
        media->setCurrentSource(QUrl::fromLocalFile(QFileDialog::getOpenFileName(0,QString("Select a file to play"),QString())));
        media->play();
    }


    By the way the beginners will probably be interested by the first task.
    int main(int argc, char **argv)
    {
        QApplication app(argc, argv);
        QApplication::setApplicationName("Phonon Tutorial 2");
        MainWindow mw;
        mw.show();
        return app.exec();
    }


    #include "main.moc"
    </syntaxhighlight>


    =Build=
    As usual, we use CMake for build operations:


    [[Category:KDE4]]
    == CMakeLists.txt ==
    [[Category:Phonon]]
    You need a file CMakeLists.txt to compile the software:
    <syntaxhighlight lang="cmake">
    project (phonon_tutorial1)
    find_package(KDE4 REQUIRED)
    include (KDE4Defaults)
    include_directories(${KDE4_INCLUDES})
    set(phonon_tutorial1_SRCS main.cpp)
    kde4_add_executable(phonon_tutorial1 ${phonon_tutorial1_SRCS})
    target_link_libraries(phonon_tutorial1 ${KDE4_KDEUI_LIBS} ${PHONON_LIBS})
    install(TARGETS phonon_tutorial1  ${INSTALL_TARGETS_DEFAULT_ARGS})
    </syntaxhighlight>
     
    ==Make And Run==
    <syntaxhighlight lang="bash">
    cmake . && make && ./phonon_tutorial1
    </syntaxhighlight>
     
    = Getting More Help =
    To talk among phonon experts, point your irc client to the server irc.freenode.org, channel #kde-multimedia
     
    = See Also =
    * [[/Python]] - same example in Python

    Latest revision as of 11:51, 31 May 2019

    Warning
    This page needs a review and probably holds information that needs to be fixed.

    Parts to be reviewed:

    Port to KF5
    Warning
    This section needs improvements: Please help us to

    cleanup confusing sections and fix sections which contain a todo


    Introduction

    By getting involved with Phonon, you can choose between three different main tasks.

    • Using the Phonon API, which allows you to develop your own multimedia application. This is discussed here.
    • Hacking the Phonon library.
    • Writing Phonon backend, this consists in writing interfaces that allows Phonon to use different sound/video engine. This usually requires good skills and knowledge of the engine you interface with.

    Abstract

    The following example lets you select a music file and plays it. To change the sound device that is used by default, use the command systemsettings.

    The Code

    All the code we need will be in one file, main.cpp. Create that file with the code below:

    #include <phonon/mediaobject.h>
    #include <phonon/audiooutput.h>
    
    #include <QFileDialog>
    #include <QtGui/QApplication>
    #include <QtGui/QMainWindow>
    #include <QUrl>
    
    class MainWindow : public QMainWindow
    {
        Q_OBJECT
        public:
            MainWindow();
    };
    
    MainWindow::MainWindow()
    {
        Phonon::MediaObject* media = new Phonon::MediaObject(this);
        Phonon::createPath(media, new Phonon::AudioOutput(Phonon::MusicCategory, this));
        media->setCurrentSource(QUrl::fromLocalFile(QFileDialog::getOpenFileName(0,QString("Select a file to play"),QString())));
        media->play();
    }
    
    int main(int argc, char **argv)
    {
        QApplication app(argc, argv);
        QApplication::setApplicationName("Phonon Tutorial 2");
        MainWindow mw;
        mw.show();
        return app.exec();
    }
    
    #include "main.moc"
    

    Build

    As usual, we use CMake for build operations:

    CMakeLists.txt

    You need a file CMakeLists.txt to compile the software:

    project (phonon_tutorial1)
    find_package(KDE4 REQUIRED)
    include (KDE4Defaults)
    include_directories(${KDE4_INCLUDES})
    set(phonon_tutorial1_SRCS main.cpp)
    kde4_add_executable(phonon_tutorial1 ${phonon_tutorial1_SRCS})
    target_link_libraries(phonon_tutorial1 ${KDE4_KDEUI_LIBS} ${PHONON_LIBS})
    install(TARGETS phonon_tutorial1  ${INSTALL_TARGETS_DEFAULT_ARGS})
    

    Make And Run

    cmake . && make && ./phonon_tutorial1
    

    Getting More Help

    To talk among phonon experts, point your irc client to the server irc.freenode.org, channel #kde-multimedia

    See Also