ObjectDescription Class Reference
(Phonon::ObjectDescription)
[Phonon module]

Detailed Description

The ObjectDescription class provides information about Phonon objects.

Phonon currently uses this class to describe audio effects and audio output devices - using the typedefs AudioOutputDevice and EffectDescription. The type of an ObjectDescription is also described through the ObjectDescriptionType enum. Objects of the same type are uniquely identified by an index().

The class gives a description() and a name() of the object, both of which are strings appropriate for end users of a Phonon application. You can also check whether the device or effect described is valid. This does not guarantee that the device or effect functions as expected, but that the ObjectDescription describes an existing device or effect.

Audio output devices and effect descriptions are used to select the audio output device to be used for playback and to create effects; we show examples of this in the snippet below. The available descriptions can be fetched with availableAudioOutputDevices() and availableAudioEffects() static functions in the Phonon::BackendCapabilities namespace

     QList<Phonon::EffectDescription> effectDescriptions =
             Phonon::BackendCapabilities::availableAudioEffects();

     QList<Phonon::AudioOutputDevice> audioOutputDevices =
             Phonon::BackendCapabilities::availableAudioOutputDevices();

     foreach (Phonon::EffectDescription effectDescription, effectDescriptions) {
         Phonon::Effect *effect = new Phonon::Effect(effectDescription);

         // ... Do something with the effect, like insert it into a media graph
     }

     Phonon::AudioOutput *audioOutput = new Phonon::AudioOutput;

     audioOutput->setOutputDevice(audioOutputDevices[0]);

Other types of ObjectDescriptions might be possible in the future, e.g., descriptions of audio capture devices, such as microphones.

See also Phonon::AudioOutputDevice, Phonon::EffectDescription, Capabilities Example, and Phonon Module.

Member Function Documentation

     QList<Phonon::AudioOutputDevice> audioOutputDevices =
             Phonon::BackendCapabilities::availableAudioOutputDevices();