Protocol

FxCustomParameterActionAPI

The FxCustomParameterActionAPI protocol defines the methods the host application provides to support a custom parameter view.

Declaration

@protocol FxCustomParameterActionAPI

Overview

Because custom parameter views may get user events at any time, this protocol provides methods to prepare the host application for those changes or other actions at arbitrary times.

It is not safe to get or set parameter values outside of a startAction:/endAction: block. For example, when a custom-parameter view receives a keyDown: event, it may need to change its parameter value. The following code fragment shows the proper sequence:

id <FxCustomParameterActionAPI> actionAPI = [apiManager apiForProtocol:FxCustomParameterActionAPI];
 
id <FxParameterSettingAPI> settingAPI = [apiManager apiForProtocol:FxParameterSettingAPI];
 
double time = [actionAPI currentTime];
 
[actionAPI startAction:self];
[settingAPI setCustomParameterValue:myObject toParm:myParameterID];
[actionAPI endAction:self];

Topics

Grouping Parameter Changes

- startAction:

Informs the host application that the plug-in will begin accessing parameters.

Required.

- endAction:

Informs the host application that the plug-in is done accessing parameters.

Required.

Getting the Current Time

- currentTime

Returns the current time, expressed in canonical frames.

Required.

Relationships