Class MediaNode

  extended by com.trolltech.qt.internal.QSignalEmitterInternal
      extended by com.trolltech.qt.QSignalEmitter
          extended by com.trolltech.qt.QtJambiObject
              extended by com.trolltech.qt.phonon.MediaNode
All Implemented Interfaces:

public final class MediaNode
extends QtJambiObject

The MediaNode class is the base class for all nodes in a media graph. In all phonon applications, one builds a media graph consisting of MediaNodes. The graph will take multimedia content, e.g., from a file, as input. After its nodes have processed the multimedia, the graph will output the media again, e.g., to a sound card.

The multimedia content is streamed over Paths between the nodes in the graph. You can query the paths that are connected to a media node with inputPaths() and outputPaths().

You can check whether the node is implemented by the current backend by calling isValid(). This does not guarantee that an instance of the class works as expected, but that the backend has implemented functionality for the class.

Currently, Phonon has four media nodes: MediaObject, AudioOutput, VideoWidget, and Effect. Please refer to their class descriptions for details about their usage, and to find out which nodes can be connected to each other. See also Building Graphs in Phonon's overview document.

Two nodes are connected to each other using the Phonon::createPath() or Path::insertEffect() functions (only Phonon::Effects use insertEffect()). We show a code example below, in which we build a media graph for video playback and then query its media nodes for their Paths:

    MediaObject mediaObject = new MediaObject();
    AudioOutput audioOutput = new AudioOutput();
    VideoWidget videoWidget = new VideoWidget();

    Phonon.createPath(mediaObject, audioOutput);
    Phonon.createPath(mediaObject, videoWidget);

    List<Path> inputPaths =
        audioOutput.inputPaths();   // inputPaths = [ mediaObject ]
    List<Path> outputPaths =
        mediaObject.outputPaths(); // outputPaths = [ audioOutput, videoWidget ]
When you create a Phonon application, you will likely build the graph yourself. This makes isValid() the most useful function of this class. The other two functions help navigate the graph, which you do not need to do as you created the nodes yourself.

See also:
Phonon Overview, Phonon::MediaObject, Phonon::AudioOutput, Phonon::VideoWidget, and Phonon Module.

Nested Class Summary
Nested classes/interfaces inherited from class com.trolltech.qt.QSignalEmitter
QSignalEmitter.AbstractSignal, QSignalEmitter.Signal0, QSignalEmitter.Signal1, QSignalEmitter.Signal2, QSignalEmitter.Signal3, QSignalEmitter.Signal4, QSignalEmitter.Signal5, QSignalEmitter.Signal6, QSignalEmitter.Signal7, QSignalEmitter.Signal8, QSignalEmitter.Signal9
Nested classes/interfaces inherited from class com.trolltech.qt.internal.QSignalEmitterInternal
Field Summary
Fields inherited from class com.trolltech.qt.internal.QSignalEmitterInternal
Method Summary
 java.util.List inputPaths()
          Returns the paths that inputs multimedia to this media node.
 boolean isValid()
          Returns true if the backend provides an implementation of this class; otherwise returns false.
 java.util.List outputPaths()
          Returns the paths to which this media node outputs media.
Methods inherited from class com.trolltech.qt.QtJambiObject
dispose, disposed, equals, finalize, reassignNativeResources, tr, tr, tr
Methods inherited from class com.trolltech.qt.QSignalEmitter
blockSignals, disconnect, disconnect, signalsBlocked, signalSender, thread
Methods inherited from class com.trolltech.qt.internal.QSignalEmitterInternal
Methods inherited from class java.lang.Object
clone, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
Methods inherited from interface com.trolltech.qt.QtJambiInterface
disableGarbageCollection, nativeId, nativePointer, reenableGarbageCollection, setJavaOwnership

Method Detail


public final java.util.List inputPaths()
Returns the paths that inputs multimedia to this media node.

See also:


public final boolean isValid()
Returns true if the backend provides an implementation of this class; otherwise returns false.

This does not guarantee that instances of the class works as expected, but that the backend has implemented the functionality for this class. For instance, Qt's GStreamer backend will return true for instances of the AudioOutput class, even if there is a problem with GStreamer and it could not play sound.


public final java.util.List outputPaths()
Returns the paths to which this media node outputs media.

See also: