[lazarus] GTK team: please specify!

Mattias Gaertner nc-gaertnma at netcologne.de
Sat Nov 1 14:05:18 EST 2003


On Sat, 01 Nov 2003 11:41:43 +0100
Micha Nelissen <M.Nelissen at student.tue.nl> wrote:

> Mattias Gaertner wrote:
> 
> > On Fri, 31 Oct 2003 18:07:58 +0100
> > Micha Nelissen <M.Nelissen at student.tue.nl> wrote:
> >>
> >>I think we're making this WAY too difficult and hackish with DC 
> >>size/position calculations all over the place.
> > 
> > 
> >>I suggest making the grabbers windows, derivative of a TCustomForm or
> >so.>
> >>I suggest using a window, derivative of TCustomForm, for drawing 
> >>invisible components on.
> > 
> > 
> > I'm not sure, what you mean. Can you give more details?
> 
> In win32 (and I guess in gtk also), windows have a certain z-ordering 
> that can be influenced. (BringToFront, SendToBack and friends). Now if 
> we make a special designer-type window, call it container, (which 
> doesn't have to be in the LCL), in which we can draw what we want. So 
> each of the grabberhandles is drawn in such a container. Each of the 
> invisible components is drawn in such a container. The result is that we 
> let the interface do the position and visibility calculations (that's 
> what it's good at, after all) and we simply state their position 
> relative to their parent which are simple calculations.
> 
> Is this clearer?

Much more clearer :)
I was a little bit confused by the term "derivative of TCustomForm".

Ok, grabbers and icons can be replaced by special non LCL widgets (in win32
slang: windows).
What about the rubberband, the selection marks and the guide/snap lines?


Mattias






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