snl@edrc.cmu.edu (Sean Levy) (06/02/89)
Is there anything wrong with having a widget's SetValues() procedure
call some callbacks as a result of a state change? I have a widget that's
displaying an image of some sort at a (settable) location inside its window,
with a callback that gets called whenever the image moves. Generally, it
moves in response to mouse events, but it could also be moved by an explicit
call to XtSetValues() (to reset it to 0,0 perhaps).
--
--sean levy
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-- swick@ATHENA.MIT.EDU (Ralph R. Swick) (06/05/89)
> Is there anything wrong with having a widget's SetValues() procedure > call some callbacks as a result of a state change? Nope, not at all. You will have to be careful, however, to make sure the widget hierarchy is in a consistent state when you execute the callbacks, or carefully document the environment that the callback will see. For example, if you follow the recommended geometry management scheme the widget's geometry fields are not accurate until after all the set_values (and the final set_values_almost) methods have completed.