Path: utzoo!attcan!uunet!snorkelwacker!bloom-beacon!LARRY.MCRCIM.MCGILL.EDU!mouse
From: mouse@LARRY.MCRCIM.MCGILL.EDU
Newsgroups: comp.windows.x
Subject: Re: Finding out if you're Iconified
Message-ID: <9009201130.AA06022@Larry.McRCIM.McGill.EDU>
Date: 20 Sep 90 11:30:23 GMT
Sender: root@athena.mit.edu (Wizard A. Root)
Organization: The Internet
Lines: 47

>> I need to find out if my application is iconified (either by the
>> user or automatically by another program), or actually being
>> displayed on the screen.

Those are not the only possibilities.  For example, it could be
uniconified but completely off-screen (with tvtwm and other "virtual
desktop" window managers, this is even likely).

> I also thought that the VisibilityNotify event might do what you
> want, however the "unobscured" event is generated when uniconifying,
> but the "obscured" event is not when iconifying.  Humhhhh, I wonder
> if this is a bug?  Does iconfication qualify as "obscured?"

From the Xlib document:

	8.4.6.10.  VisibilityNotify Events
	
	The X server can report VisibilityNotify events to clients
	wanting any change in the visibility of the specified window.
	A region of a window is visible if someone looking at the
	screen can actually see it.
...
	The X server ignores all of a window's subwindows when
	determining the visibility state of the window and processes
	VisibilityNotify events according to the following:
	
	o    When the window changes state from partially obscured,
	     fully obscured, or not viewable to viewable and completely
	     unobscured, [...] VisibilityUnobscured.
	
	o    When the window changes state from viewable and completely
	     unobscured or not viewable to viewable and partially
	     obscured, [...] VisibilityPartiallyObscured.
	
	o    When the window changes state from viewable and completely
	     unobscured, viewable and partially obscured, or not
	     viewable to viewable and fully obscured, [...]
	     VisibilityFullyObscured.

Nothing about changes to non-viewable states, so no, it's not a bug.
IMO it's a misfeature, though.  Unmapping certainly changes a window's
visibility, as defined in the first paragraph quoted above.

					der Mouse

			old: mcgill-vision!mouse
			new: mouse@larry.mcrcim.mcgill.edu