You can declare a variable for a specific object type using the WithEvents keyword to get notified when an event is executed.
Public WithEvents App As AcadApplication
After the new object has been declared with events, it appears in the Object drop-down list box in the class module, and you can write event procedures for the new object in the class module. (When you select the new object in the Object box, the valid events for that object are listed in the Procedure drop-down list box.)