[lazarus] Progress

Michael A. Hess mhess at miraclec.com
Thu Sep 2 08:09:38 EDT 1999

mariano podesta wrote:
> are you sure that GTK library does not dispatch standard messages like
> 'mouse move'?
> because standard messages is all that windows do.
> mariano

GTK does not dispatch ANY messages. It handles them all internally. All
it does is fire a callback if an event has occured that it has handled.
It does the same thing we do in Delphi with the On Event stuff. In a
class we create we can assign an additional task to be completed if an
event has occured. That is all we are getting from the GTK. It has
handled the event and done whatever the control needs to have done. Then
if and only if we have assigned a callback (an onEvent in Delphi) to the
widget does it even bother to tell us about the event. That is the
callback that we receive in the LCL. Then if we have assigned an OnEvent
to the class for this type of event do we call that. We never actually
receive the message from the GTK we only get the callback or as in
Delphi the OnEvent signal that the event has occured.

In other words you can receive the callback and then determine wheither
you want the control to accept it. It has already accepted it and is
just telling you about it. If we could tell the GTK not to accept it we
wouldn't be getting the callback in the first place.

==== Programming my first best destiny! ====

Michael A. Hess      Miracle Concepts, Inc.
mhess at miraclec.com   http://www.miraclec.com

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