Type Alias

AudioUnitPropertyListenerProc

Called by the system when the value of a specified audio unit property has changed.

Declaration

typedef void (*AudioUnitPropertyListenerProc)(void *inRefCon, AudioUnit inUnit, AudioUnitPropertyID inID, AudioUnitScope inScope, AudioUnitElement inElement);

Parameters

inRefCon

Custom data that you provided when registering your callback with the audio unit.

inUnit

The audio unit upon which the specified property value has changed.

inID

The property whose value has changed.

inScope

The scope of the property whose value has changed.

inElement

The element ID on the scope of the property whose value has changed.

Return Value

A result code.

Discussion

If you named your callback function MyAudioUnitPropertyListenerProc, you would declare it like this:

Discussion

You register your AudioUnitPropertyListenerProc callback function using the AudioUnitAddPropertyListener function.

See Also

Callbacks

AUInputSamplesInOutputCallback

Called by the system when an audio unit has provided a buffer of output samples.

AURenderCallback

Called by the system when an audio unit requires input samples, or before and after a render operation.