[Qt] Some changes cause errors in qt ide under win32

[Paul Ishenin]

zeljko пишет:
> On Wednesday 18 July 2007 07:47, Paul Ishenin wrote:
>> Paul Ishenin wrote:
>> To repeat exception you need to:
>> 1. Add TPanel to form (or something else)
>> 2. Set hint to "blabla", Set ShowHint to True
>> 3. Run application and move mouse over panel
>> 4. After showing that "blabla" we get SISIGV
>>
>> Everybody wellcome to thurther investigation.
> 
> wow, THintWindow was first bug fixed by me in qt3CLX port, few years ago ;)

I created separate class for THintWindow - TQtHintWindow (probably 
temporary - for debug purposes)

So, what I digged for now:

1. THintWindow.CalcHintRect raises Qt warnings something like "it is 
dangerous to leave active Painters outside paint event" (typed from 
memory). To be more exact DrawText with DT_CALCRECT is guilty for this.

2. I added line
   Result := Format('Unknown event: %d', [QEvent_type(Event)]);
to EventTypeToStr debug function. And after that catched unknown events 
70 and 67 - they are defined only fot QT_3 support. So I think our 
bindings are compiled with Qt3 support. Do we need this? Can we remove it?

3. If I comment DrawText in THintWindow then I can catch much more 
events related to THintWindow widget. Without commenting I catch 
exception in next event after PaintEvent.

So, it is something related with using painting routines ouside paint 
event. I dont know how to solve that painting. We have many places in 
LCL where we can write such code:

   DC := GetDC()
   BitBlt(DC, ...)
   ReleaseDC(DC)

And now we have restriction that all this is possible only in paint 
events. How to move this code to paintevent????

Best regards,
Paul Ishenin.