Introduction to EON SDK - Construction IT research at VTT

User Guide
Techniques
listen to and send messages of other types. A module may also freely
define new message types that it could use when communicating with
other modules.
Following is a brief description of how you should work with module
messages.
1. To begin with, you perform module initialization. Call
IAutApp::GetToken() once for each message type you want the module
to recognize. Store all tokens for future use—you will need them to
determine the type of module message when Windows messages finally
start to arrive.
2. Then call IAutApp::ListenTo() for all the message types you'd like
EON Studio to forward to the module. As an argument, pass a handler
to the window you want to be the target for the specific message
type. The module (or rather, one of the module's windows) is now
ready to start receiving messages. It is important to note that you
should skip this step completely if you want to subscribe to menu
command messages—those messages are received without calling
IAutApp::ListenTo().
3. A WindowProc() message handler placed in the target window should
first decide whether the received Windows message is a module
message. If so, the handler must decide which type the message has—
you should compare the message token with the ones you have
previously stored (see Step 1).
4. If the message belongs to the set of module messages you're
interested in, then let the WindowProc() handler process it
accordingly. Note that you should never change the contents of the
message structure. There might be other modules that listen to the
same message type. If you modify the information, those modules
will receive corrupt messages.
Note that you should always work on copies of the original module
messages if you wish to modify the contents of the messages.
5. If necessary, make your handler call the parent message handler
CWnd::WindowsProc() and return.
No snippets of code are included in this section. However, it is
advisable to inspect the source code of the Sample Module, or read
through the ModuleView.CPP file created by the EON Module Wizard.
View handling
One of the most exciting features of creating an EON module is the
ability to seamlessly add custom views inside EON Studio. These views
are treated in the same way as any standard views. In fact, some of
the complex views (Scenegraph, Butterfly, ScriptEditor, etc) in EON
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EON SDK 2.53.0