Re: [PATCH] gtkpixmap.c, bug in gtk_pixmap_set()

[Owen Taylor <otaylor gtk org>]

Lars Hamann <lars@gtk.org> writes:

> Hi Owen!
> 
> On Thu, Jun 18, 1998 at 06:04:12PM -0400, Owen Taylor wrote:
> 
> > Thanks for the patch. Since clearing is something we want to avoid
> > if at all possible, I've changed the patch to be a bit more careful
> > about clearing, and also to delay the actual clear until just before
> > the widget is redrawn. (This works because if the allocation changes,
> > GTK+ will clear for us)
> 
> I'm not completely sure about this, but I think the patch simply won't work.
> Gtk_pixmap_set should expose the area of the pixmap. The parent of the pixmap
> has to redraw the area, because gtk_pixmap has the GTK_NO_WINDOW flag set.
> Now the pixmap simply clears the area of the pixmap.

I don't quite understand. The Pixmap still redraws it's own area -
the NO_WINDOW flags simply indicates that widget->window is the
same as parent->window; i.e., that it is drawing on its parent's
window. In this case, we simply clear the allocation when the 
needs_clear flag is set.

> I think that's the reason, why the testgtk notebook example doesn't work
> correctly.

What doesn't work correctly about it? As far as I can see, it still
looks fine.

Regards,
                                        Owen