Hi Guys,
Here is a GUI updating question.

According to the MASON manual, it says that the display should be updated 
by it self which means I don't need to bother to schedule the drawing.
But in reality I trid to rely on the customized portrayal(handles drawing by 
itself without delegatoin to the simple portrayal) to update based on the 
underlying field value change, it didn't work. Nothing was updated.
The sample files packaged with MASON never shceduled the drawing 
mechanism and they all updated properly. 

So if we add customized portryayal the updating of GUI has to be done by 
explicitly scheduling the drawing?
Does the MASON check all the portrayal's dirty flag to determine whether to 
update at each step? I don't know whether the mechanism works this way.

Regards,
Ge