Instance Property


An audio unit’s parameters, organized in a tree hierarchy.


iOS, Mac Catalyst, tvOS
@property(retain, nonatomic) AUParameterTree *parameterTree;
@property(retain, atomic) AUParameterTree *parameterTree;


Hosts can fetch this property to discover a unit’s parameters. KVO notifications are issued on this member to notify the host of changes to the set of available parameters.

Subclasses should implement this property to expose parameters to hosts. They should then cache as much data as possible and send KVO notifications on this property when altering the structure of the tree or the static information of parameters.

This version 3 property is similar to the version 2 kAudioUnitProperty_ParameterList and kAudioUnitProperty_ParameterInfo APIs.

See Also

Querying Parameters


Special read-only property for KVO.

- parametersForOverviewWithCount:

Returns the audio unit’s most important parameters.