Using the Container Callback
When an object is drawn in a container a series of states occur during the process of drawing that object. The state may be the beginning of the drawing process, a continuation of the drawing process, the ending of the drawing process, or the aborting of the drawing process. The following are the states currently supported for processing:
CONTAINER_STATE_BEGIN
CONTAINER_STATE_PROCESS
CONTAINER_STATE_END
CONTAINER_STATE_ABORT
Drawing an object within a container generates calls to the LContainer::ContainerCallback function. When the callback function receives a CONTAINER_EVENT_TYPE_DRAW event, information concerning the object being processed is also sent to the callback function in the pEventData parameter. This information includes the current state of the drawing.
Before LContainer::ContainerCallback can be used, it must be enabled using the LContainer::EnableContainerCallback function.