[lazarus] GTK team: please specify!

Mattias Gaertner nc-gaertnma at netcologne.de
Sun Nov 2 09:45:06 EST 2003

On Sun, 2 Nov 2003 15:03:10 +0100
Mattias Gaertner <nc-gaertnma at netcologne.de> wrote:

> > The WinAPI specifies that GetDC(GetDesktopWindow()) should return a 
> > device context of the screen. We can use this DC to draw on.
> Very funny. ;)
> What has the winapi to do with the gtk?
> We need the window DC without clipping and we need an event to know, when
> the gtk has finished painting everything. And during moving we have to
> paint as well.
> When we got this, we can omit the paint on every message and we can omit
> the designer widgets, because the rest is already implemented. This
> solution would be very near to my initial wish in a former mail.
> I will do some experiments... 

Ok. Maybe I found the solution.
Now to the LCL.

GetDC will just return the "normal" device context for a window. Under gtk
this is without the child windows (they are clipped away). 
The designer needs a DC with childs. Something like GetRawDC or GetWholeDC
or GetDCForWholeWindow or GetDesignerDC or ... . I guess under win32api this
is already the default, so you have little to do. If not, how does win32api
calls it?


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