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API Reference

IObserver_SetHandler()

Brew Release
Brew MP 1.0.2
Description
This function allows an application to hook its own event handler into the normal observer event handling mechanism. For example, a observer that derives from one of the standard observers could insert its own event handler that will be called by the base observer object each time an event is processed.
The event handler is stored in a HandlerDesc data structure as a PFNHANDLER, along with a pointer to a block of memory allocated and owned by the application. This pointer will be passed into the application's event handler with each event to be processed. The HandlerDesc data structure also contains a PFNFREEHANDLER that will be called when the observer is released so that the application may free the private memory allocated and passed to the event handler.
IObserver_SetHandler() associates a given HandlerDesc data structure with a particular observer.
Interface
Prototype
   void    IObserver_SetHandler(IObserver* pi, 
                                  HandlerDesc* pDesc);
Return
none
Side Effect
None
Comment
Passing NULL for the HandlerDesc will reset the controller's event handler to use the base controller's default event handler, without private memory or the need to free privately allocated storage.
The handler installed by a controller to process events should itself remember to call HANDLERDESC_Call() so that controller that themselves derive from this controller may also hook into the controller's event handler.
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