Defined Types



AUParameterListenerRef


An object which receives notifications of Audio Unit parameter value changes.

typedef struct AUListenerBase *AUParameterListenerRef; 

AUEventListenerRef


An object which receives Audio Unit events.

typedef AUParameterListenerRef AUEventListenerRef; 
Discussion

An AUEventListenerRef may be passed to API's taking an AUEventListenerRef as an argument.


AudioUnitEvent


Describes a change to an Audio Unit's state.

See Also:
AudioUnitEvent
typedef struct AudioUnitEvent { 
    AudioUnitEventType mEventType; 
    union { 
        AudioUnitParameter mParameter; // for parameter value change, begin and end gesture 
        AudioUnitProperty mProperty; // for kAudioUnitEvent_PropertyChange 
        } mArgument; 
} AudioUnitEvent; 
Field Descriptions
mEventType
The type of event.
mArgument
Specifies the parameter or property which has changed.

AUParameterListenerProc


A function called when a parameter value changes.

typedef void (*AUParameterListenerProc)(
    void *inRefCon, 
    void *inObject, 
    const AudioUnitParameter *inParameter, 
    Float32 inValue); 
Parameter Descriptions
inRefCon
The value passed to AUListenerCreate when the callback function was installed.
inObject
The object which generated the parameter change.
inParameter
Signifies the parameter whose value changed.
inValue
The parameter's new value.

AUParameterListenerProc


A function called when an Audio Unit event occurs.

See Also:
AUEventListenerProc
typedef void (*AUEventListenerProc)(
    void *inCallbackRefCon, 
    void *inObject, 
    const AudioUnitEvent *inEvent, 
    UInt64 inEventHostTime, 
    Float32 inParameterValue); 
Parameter Descriptions
inCallbackRefCon
The value passed to AUListenerCreate when the callback function was installed.
inObject
The object which generated the parameter change.
inEvent
The event which occurred.
inEventHostTime
The host time at which the event occurred.
inParameterValue
If the event is parameter change, the parameter's new value (otherwise, undefined).

AUEventListenerProc


A function called when an Audio Unit event occurs.

See Also:
AUParameterListenerProc
typedef void (*AUEventListenerProc)(
    void *inCallbackRefCon, 
    void *inObject, 
    const AudioUnitEvent *inEvent, 
    UInt64 inEventHostTime, 
    Float32 inParameterValue); 
Field Descriptions
inCallbackRefCon
The value passed to AUListenerCreate when the callback function was installed.
inObject
The object which generated the parameter change.
inEvent
The event which occurred.
inEventHostTime
The host time at which the event occurred.
inParameterValue
If the event is parameter change, the parameter's new value (otherwise, undefined).

(Last Updated July 18, 2005)