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 February 2007.
    In order to make the revision process clear, I introduce a confident index, "0" means nobody except me has reviewed 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}}
    You can contact me on #phonon on the irc.freenode.org to give me any feedback, usually I'm using the nickname "lucas" or other variants.
    ----


    =Introduction=
    = Introduction =
    ''Confident Index =0''
    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 <tt>systemsettings</tt>.
     
    =The Code=
    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>
     
    #include <QFileDialog>
    #include <QtGui/QApplication>
    #include <QtGui/QMainWindow>
    #include <QUrl>
     
    class MainWindow : public QMainWindow
    {
        Q_OBJECT
        public:
            MainWindow();
    };


    The following is based on the documentation available here
    MainWindow::MainWindow()
    [http://www.englishbreakfastnetwork.org/apidocs/apidox-kde-4.0/kdelibs-apidocs/phonon/html/index.html Phonon API].
    {
        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 getting involved with Phonon, you can choose between three different main tasks.
    int main(int argc, char **argv)
    * '''Using the Phonon API''', which allows you to develop your own multimedia application. In fact any application which needs sound can take benefits from the phonon API. In the tutorials showing the API we will learn how to set up the development environment with kdevelop 3.4.  
    {
        QApplication app(argc, argv);
        QApplication::setApplicationName("Phonon Tutorial 2");
        MainWindow mw;
        mw.show();
        return app.exec();
    }


    * '''Hacking the Phonon library''', (try to develop more this topic).
    #include "main.moc"
    </syntaxhighlight>


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


    Beginners will probably be more interested by the first task.
    == CMakeLists.txt ==
    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


    [[Category:KDE4]]
    = See Also =
    [[Category:Phonon]]
    * [[/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