on 8/24/00 9:41 AM, Kent Quander at [EMAIL PROTECTED] wrote:
> Some time ago I ran into the issue where the screen is not restored after a
> popup alert goes away. This effects me since I do a lot of custom drawing
> on forms. It is particularly an issue on the Symbol units ... after the
> scanMgr library is loaded, a fellow only has about 5K of dynamic memory to
> work with. (the SPT1700's seem to be the most restrictive in this regard).
> Anyway, I "solved" the problem by wrapping the FrmCustomAlert() routine as
> follows:
If you are doing your own drawing, you must provide your own frmUpdateEvent
case in your form event handler. The default frmUpdateEvent (handled by the
OS if you don't) redraws the form - on later versions of the OS this means
the form is erased first, then the title and bounds (if modal) are drawn,
then the form objects are told to draw. If you are doing any drawing on the
form yourself (gadgets, etc.), you need to do the following in your event
handler:
case frmUpdateEvent:
FrmDrawForm(FrmGetActiveForm());
// Call your drawing routine here
fHandled = true; // Override the default behavior
break;
Also, check the Save Behind box for dialogs (modal forms). The system will
try to save the screen bits underneath the dialog/alert offscreen if
possible (for restoration when the dialog/alert is erased), but if there is
not enough dynamic heap available to support this, an update event is added
to the event queue instead.
For a complete discussion of the default system behavior for different event
types and form objects, see Knowledge Base article #1788 (User Interface).
-JB
----------------------------------------------
JB Parrett [EMAIL PROTECTED]
Palm, Inc.
We grow a lot faster than trees,
so we miss a lot of stuff. - B. Andreas
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