Documents: 3 Basic DC Messages

The document control objects use messages for many things. Since well over half a dozen classes of objects (counting file selectors, GenDisplayGroup objects, menu triggers, etc.) and far more actual objects are involved in intricate tasks, many messages are continually sent back and forth. Most of these messages are transparent to the programmer. The programmer need only know about them if the program subclasses a message to add functionality to it; this is an advanced technique which few programs will ever need to use.

There are two basic types of messages the programmer needs to know about. First, there are messages which are sent to document control objects; these objects may query information, toggle some functionality, or otherwise instruct the DC objects to take some action. Second, there are messages the DC objects send when the programmer's code needs to take some action. Each type of message is treated in a separate section.