with 3.5 if you use a callback function for your gadget (available only from 3.5
on), FrmDrawForm will redraw your gadgets.
-Ezekiel Sanborn de Asis
on 9/4/00 5:01 AM, [EMAIL PROTECTED] at [EMAIL PROTECTED] wrote:
> I emulated my program for Palm IIIc and 3.5 color debug rom.
> It turns out that the system does not redraw screen after
> alerts and dialogs. Is this a known problem?
This is covered in more detail in the Palm OS 3.5 page at palmos.com, but
the basics are:
1. If you've set the Save Behind bit for a form, the system tries to save
the screen bits that will be covered up when the form appears. If there is
enough memory to do perform the save, the bits are restored to the screen
when the form is erased. If there is not enough memory, the system simply
sends an update event to the underlying form.
2. The default frmUpdateEvent, handled by the OS in FrmHandleEvent(), calls
FrmDrawForm() for your form.
3. FrmDrawForm() redraws the form's parts (title, border) and then calls the
drawing routines of all the form's objects (except gadgets). However, it had
what I would call a bug in the versions of the OS prior to OS 3.5 - it would
not erase the form first. Under OS 3.5, it does the erase first.
4. If you do any explicit drawing on your form (e.g., within a gadget), you
must include a case for frmUpdateEvent in your form's event handler. In this
case, call FrmDrawForm() yourself, then call your drawing code, then return
true from your event handler so the default behavior does not take place.
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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