RE: drop-down menu with multiwindow option doesn't work

["Phil Betts" <Phil dot Betts at ascribe dot com>]

Raphaël Langella wrote:
> Hi,
> I'm using Tecplot 360, a proprietary program written with a Motif
> toolkit. It runs on a Linux server and the display is a win2k PC
> with cygwin X Server 1.5.3. The problem only happens with the
> multiwindow option.
> 	The problem is with the drop-down menu. When I click it, it
> seems the menu appears behind the window and immediately disappear.
> I made a screenshot of it but didn't attached it because I'm not
> sure about the file attachment policy of the mailing list. There's
> a grey rectangle that briefly appears under the window. It's plain
> grey, with no text in it.
> 	I understand that the problem is probably related to the
> Windows wm, since it doesn't show up without the multiwindow
> option, but I was wondering if it's a known bug. Or maybe it's
> win2k specific?
> 	I've got a workaround: rootless option and any Unix wm, but I'd
> like to understand what is causing this problem.
> Thanks for your attention.
> 
> Raphaël Langella

I was waiting to see if you got a reply from someone else, as I
don't really have a solution for you.  However, Windows seems to 
have real difficulties with Z-ordering: MS Word opens a new 
document beneath an existing one, modal dialogs often open below 
the parent window (which is a real PITA because you can't move the 
parent!), always-on-top widgets are often hidden below something 
else, and desktop widgets obscure application windows. (Only MS 
has the resources to screw up such a simple concept so 
comprehensively!)

Having said that, I use emacs on X every day, and I can't remember
its menus ever appearing below the main window (except perhaps a 
very early version of XWin.  The emacs version I run was compiled 
to use the X toolkit.  I would guess that when Motif creates the 
window for the menu, it's not setting a hint which multiwindow mode 
requires in order to force the correct Z-order.  It might be worth
checking what the difference is between Xt menu creation and Motif
menu creation.

If that's the case, it's not clear where the "blame" lies.  It might
be that Motif just happens to work on UNIX based servers, and XWin
just exposes a long-standing bug.  Conversely, it may be that XWin
is misinterpreting the hints that Motif sets up, and doesn't set up
the Windows' window with the correct flags.

Perhaps Yaakov or Jon could shed more light on this?

In the meantime, I think you've already found the best workaround.

I suspect the reason the menu window disappears is because your
mouse is still in the parent window, and gives it the focus, so 
Motif thinks you've moved off the menu and closes it.

Phil
-- 


This email has been scanned by Ascribe Ltd using Microsoft Antigen for Exchange.

--
Unsubscribe info:      http://cygwin.com/ml/#unsubscribe-simple
Problem reports:       http://cygwin.com/problems.html
Documentation:         http://x.cygwin.com/docs/
FAQ:                   http://x.cygwin.com/docs/faq/