Phonon

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

• /Python - same example in Python