[lazarus] Non-visual component drawing

Micha Nelissen M.Nelissen at student.tue.nl
Mon Oct 27 13:49:02 EST 2003

Nelissen, M. wrote:
> Mattias Gaertner wrote:
>>On Mon, 27 Oct 2003 16:23:16 +0100
>>Micha Nelissen <M.Nelissen at student.tue.nl> wrote:
>>>On second thought, it does get executed, but GetDeviceSize is not 
>>>implemented for win32, because it is not possible to retrieve the size 
>>>of a device context given a specific handle. Please advise :(.
>>Is it possible to find out, if a handle is a window and return the size?
> The handle is a device context, an HDC. It is possible to find out the 
> size of a window, for example using GetWindowRect, but that function 
> wants an HWND, not an HDC.

Ok, I have implemented this using WindowFromDC and similar tricks.

However, now a new incompatibility surfaces: what coordinates is 
TInterfaceObject.GetWindowOrgEx supposed to return? In screen 
coordinates or in client? I have this feeling gtk returns relative to 
screen origin, while win32 returns relative to client origin.


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