RegisterPSEvent

This member function registers an application object to receive notifications of PS update events. To use this function the application must create an object derived from either ECLPSNotify or ECLPSListener. A pointer to that object is then passed to this registration function. Any number of notify or listener objects may be registered at the same time. The order in which multiple listeners receive events is not defined and should not be assumed.

Different prototypes for this function allow different types of update events to be generated, and different levels of detail about the updates. The simplest update event is registered with an ECLPSNotify object. The type of registration produces an event for every PS update. No information about the update is generated. See the description of the ECLPSNotify object for more information.

For applications with need more information about the update, the ECLPSListener object can be registered. Registration of this object gives the application the ability to ignore some types of updates (for example, local terminal functions such as keystrokes) and to determine the region of the screen which was updated. See the description of the ECLPSListener object for more information. When registering an ECLPSListener object, the application can optionally specify the type of updates which are to cause events.

After an ECLPSNotify or ECLPSListener object is registered with this function, it's NotifyEvent() method will be called whenever a update to the presentation space occurs. Multiple updates to the PS in a short time period may be aggregated into a single event.

The application must unregister the notify/listener object before destroying it. The object will automatically be unregistered if the ECLPS object is destroyed.