[lazarus] Win32 bug: tcontrol's painting themselves intgroupboxes

Mattias Gaertner nc-gaertnma at netcologne.de
Mon Sep 1 03:34:48 EDT 2003

On Sun, 31 Aug 2003 20:59:49 +0200
Micha Nelissen <M.Nelissen at student.tue.nl> wrote:

> Mattias Gaertner wrote:
> > On Sun, 31 Aug 2003 18:54:50 +0200
> > Mattias Gaertner <nc-gaertnma at netcologne.de> wrote:
> > 
> > 
> >>On Sun, 31 Aug 2003 16:58:18 +0200
> >>Micha Nelissen <M.Nelissen at student.tue.nl> wrote:
> >>
> >>
> >>>Hi,
> >>>
> >>>The problem is the following: if a tcontrol paints itself to it's
> >parent>>
> >>>DC, and the parent's clientrect is different than the origin, the 
> >>>tcontrol's will paint themselves to the wrong position, namely the 
> >>>parent.topleft, not the topleft of the clientrect. This happens with 
> >>>TColorButton's in TGroupboxes for example. How do we solve this?
> >>>
> >>>FYI: Delphi has not solved this, a control at position (0,0) in a 
> >>>tgroupbox is painted on top of the caption, while we want it in the 
> >>>clientrect.
> >>
> >>Right.
> >>An additional problem is, that the gtk paints before and the win32 paint
> >>during message handling and they both uses different DC origins. There
> >are>plenty of possibilities, where the origin can be moved to fix this. I
> >will>also look into this ...
> > 
> > 
> > Maybe I find a solution.
> Hmm, not quite :(. The groupbox caption is not drawn anymore. It seems 
> the window rect has stayed in the same position, but the whole box has 
> moved up. Difference in top position of tcontrols and twincontrols has 
> stayed the same.

Hmm. It works for me. I have to test more examples...
BTW, GetCLientBounds was not implemented and so I started it. It is not
complete yet. 

I think, it would help, to have a place, where all the todos and small bugs
of the win32 intf can be added. The roadmap only shows the captions and it
takes a lot of time to click on every item. A list with a caption and a
description for each item. Is this possible?
If not, I will start a todo.txt.


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