[lazarus] GTK team: please specify!
nc-gaertnma at netcologne.de
Sun Nov 2 10:16:11 EST 2003
On Sun, 2 Nov 2003 17:22:10 +0100 (CET)
Michael.VanCanneyt at wisa.be wrote:
> On Sun, 2 Nov 2003, Mattias Gaertner wrote:
> > 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?
> Maybe a stupid suggestion, but why don't you draw all that on the form
> window/canvas ? All widgets/controls must always be somewhere on the
> form. Also, if you move widgets over parent boundaries (which can happen)
> the designer handles can still be drawn, since their coordinates are
> relative to the form window, not relative to the parent.
Because I didn't know the trick to get a device context for this, the gtk
interface was young and unflexible and the message queue unordered. Now, I
know the trick and the gtk interface has everything we need. Now I will do
Because this was always my goal, the designer needs only little changes for
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