I'm stumped on this, hoping someone can help...

I have a form, the main item on the form is a list. From this form, you 
can tap a button, that brings up a modal dialog to let you create a new 
item for the list. That all works fine.

After the new item is created, I append it to the list and call 
LstSetSelection so that it is highlighted and the list scrolls to make 
it visible (although in OS 3.1, the list doesn't scroll, is this a known 
bug? But that's a side issue...).

After the modal dialog is dismissed, the form gets an update event, and 
I dutifully call FrmDrawForm. Really I do.

Here's where the fun starts: I also have a key handling function in my 
event handler, so the user can use the hard scroll buttons to move the 
list selection up and down (it calls LstSetSelection to do the work). 

If, immediately after creating a new item, I try to use the scroll 
buttons, the debug ROMs report the "calling a draw function without a 
valid draw context" error. But I have just called FrmDrawForm in the 
update handler! So I simply don't understand how I could have lost the 
draw context in the meantime.

If I tap on the list first, everything is fine.

Does anyone have any clues how this can happen? The error shows up on OS 
3.5 and up, not on earlier OSes.

As I said, I'm currently stumped, though still tracing through trying to 
figure it out. Any suggestions would be appreciated.

Dave Johnson

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