Phonon: Difference between revisions

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These tutorials are now under construction, please be patient.
{{Review|Port to KF5}}
=Introduction=
The following is based on the documentation available here.
[http://www.englishbreakfastnetwork.org/apidocs/apidox-kde-4.0/kdelibs-apidocs/phonon/html/index.html Phonon API]
Getting involved with Phonon consists in three different main tasks.
* '''Using the Phonon API''', which allows you to develop your own multimedia application.
* '''Hacking the Phonon library''' (try to develop more this topic).


* '''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.
{{Improve}}


By the way the beginners will probably be interested by the first task.
= 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.


[[Category:KDE4]]
=Abstract=
[[Category:Phonon]]
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();
};
 
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"
</syntaxhighlight>
 
=Build=
As usual, we use CMake for build operations:
 
== 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
 
= 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