This method handles model change notifications while the editor is active. See PropertyEditorModule::ModelChanged for more information.
virtual int ModelChanged( int index, int element, int changeType, Node * pNode )
The return value is a PropertyEditorModule_ModelChangedCodes value indicating the module's response to the change. For example Node editors return PEMMCC_Clear to cancel the editor when notified that one or more of the nodes being edited has been removed from the database.