Re: Backend <-> GUI Library Interaction

[Christopher Armstrong]

Sheldon Gill wrote:
> Christopher Armstrong wrote:
> > There are outstanding issues with the windows backend related to window
> > management. I believe some of these can be fixed by responding to
> > certain Win32 window messages that MSWindows posts out. I am referring
> > to the problems with window layering/levels/ordering and related focus
> > issues that seem to affect everything from windows going missing to
> > modal windows playing up. 
>
> Not to mention the click twice to edit problem ;)
What is this one exactly? Is it needing to focus a window before it 
responds to mouse events?

> > application was given/lost the keyboard focus), WM_ACTIVATEAPP (your
> > application itself lost/gained the keyboard focus) and
> > WM_WINDOWPOSCHANGING/WM_WINDOWPOSCHANGED (called for a litany of window
> > resize/move/focus/Z-order events where the outcome can be "adjusted"). I
> > think these could help.
> Win32 provides some window messages such as WM_ACTIVATE (a window in an
>
> Probably, although correcting calls to SetWindowPos() should fix the 
> vast majority of problems.
It's not just that. A window can be brought to the front of the Z-order 
by simply clicking on it in Windows; that's what is expected to happen. 
Windows doesn't have any concept of window levels, except with modal 
windows and "Always on top", which are just hacks anyway. 
WM_WINDOWPOSCHANGING allows the programmer to intercept any sort of 
move/size/z-order change event and modify the outcome, including 
rejecting the change. This is needed to prevent windows going under 
other windows when a dialog box is running modal, and to make sure menus 
and their counterparts appear to "float". Currently, windows just get 
reordered by normal Win32 ordering rules: user clicks on window, window 
is brought to top of Z-Order. This needs to be fixed.

Cheers
Chris