[Pkg-tcltk-devel] Bug#514115: Log of a chat session with one of Tk on X Window maintainers regarding this issue

[Konstantin Khomoutov]

I've talked about this very issue with one of Tcl Core Team members,
Joe English, on 2008-01-21 in the Tcler's chatroom. Since the server 
running that room doesn't provide convenient chat logs accessible via 
WWW, here's the relevant part of the discussion (with kostix being me 
and jenglish being Joe English) -- it (possibly) clarifies the subject 
and the position of one of the chief Tk developers on this issue:

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[03:40] kostix	ok, the question: when we implemented raising tkabber 
from a tray icon, it seemed to misbehave under metacity and kwin (IIRC). 
today I've been shown this bugreport regarding raising Tk windows under 
metacity: http://bugzilla.gnome.org/show_bug.cgi?id=567528 -- it states 
that instead of XRaiseWindow a well-behaving app should set some 
property (?) somewhere. what do you think about this?

[03:40]	kostix	some _NET_ACTIVE_WINDOW messages

[03:40]	jenglish	kostix -- I think this is a known issue.

[03:40]	kostix	Tk really uses XRaiseWindow and it's documentation sounds 
ok to me

[03:40]	   * jenglish downloading ...

[03:41]	jenglish	... part 1 of the known issue is that X clients don't 
get to say "raise this window" -- they just get to say "Dear WM, please 
if you would be so kind, raise this window for me."

[03:43]	jenglish	(That's *always* been the case, since the dawn of the 
ICCCM.  Nobody noticed until recently, 'cause up til now WMs have always 
complied with those requests.)

[03:46]	jenglish	... looks like this is not really a bug.  Comment #9 
from HP is correct.

[03:47]	kostix	jenglish: but it clearly states "you should file a 
bug..." -- how do you interpret that?

[03:47]	kostix	or it just means "either way is ok if it's properly 
documented"?

[03:48]	jenglish	Quoth HP: "If they have an API meaning "bring this 
window to user's attention" and they use XRaiseWindow() to mean that, 
then yes, you should file a bug with them."

[03:49]	jenglish	Tk doesn't have an API meaning "bring this window to 
user's attention."

[03:49]	jenglish	It has [raise], which means "Please dear WM bring this 
window to the top of the stacking order if it's not too much of a bother..."

[03:50]	kostix	jenglish: how "bring to the user attention" would be 
different then? say, flash a window's frame without moving it from its 
layer?

[03:53]	jenglish	"bring to the user's attention" is a fairly recent 
invention (circa 2002?).  Tk just hasn't caught up yet.

[03:54]	jenglish	Note that Windows XP and later has similar issues.

[03:54]	patthoyts	On windows it occurs as a side-effect of [raise]

[03:54]	kostix	eh? I know about FlashWindow(), is it this?

[03:54]	patthoyts	yeah

[03:55]	patthoyts	Although its called through SetForegroundWindow

[03:55]	patthoyts	If your app isn't foreground then the wm will not let 
it raise tot he top but calls FlashWindow instead.

[03:55]	jenglish	That's what happens under metacity and kwin, too.

[03:56]	   * jenglish in the case of kwin, it depends on user 
preferences, of course.

[03:56]	kostix	well, this might have sense

[03:57]	kostix	but the modal dialog box anyway pops the window in front 
of me in windows, IIRC

[04:00]	patthoyts	Not for me. If I do [after 2000 [list raise .]] and 
swith to firefox, it doesnt let tkchat raise over firefox.

[04:00]	patthoyts	We had a discussion about this here a few days ago. 
There is evidently some setting in windows that disables this as having 
a flashing taskbar item for this is normal on XP but some people dont 
get that.

[04:01]	kostix	hm, I'm sure I had cursed this behaviour under certain 
circumstances

[04:01]	kostix	may be another window of a currently active app?

[04:01]	jenglish	That's how current X WMs do it too.

[04:04]	jenglish	Wait, kostix -- this bug report pertains to tkabber?  A 
chat/IM client?

[04:04]	jenglish	Please, I beg you: stop trying to do whatever it is 
you're trying to do.

[04:05]	kostix	jenglish: that concrete bug I showed? no. but it was 
brought to my attention because of this

[04:05]	jenglish	This whole _NET_WM_DEMANDS_ATTENTION / flashing taskbar 
/ [raise] doesn't work anymore thing is part of an ever-escalating war 
between window managers and applications.

[04:06]	kostix	jenglish: the idea was to unconditionally bring tkabber's 
window to front on a left mouse-button click on the tray icon. on some 
WMs it didn't work well

[04:06]	jenglish	Exactly.

[04:06]	kostix	"the old ones" like fvwm did OK

[04:08]	jenglish	Newer WMs don't let you do that any more.

[04:08]	jenglish	And the harder you try, the more they will fight back.

[04:08]	kostix	jenglish: but my case is clear "bring that bloody window 
up, I say" thing

[04:09]	jenglish	As soon as you find some way to "just make this window 
do what I want it to do", Lubos will find a way to defeat you next year.

[04:09]	jenglish	EXACTLY!  You, as an application, should NOT be saying 
"bring that bloody window up."

[04:09]	jenglish	You, as an application, get to say "Please dear WM 
bring this window to the user's attention."

[04:10]	jenglish	If the WM chooses not to comply, and instead just 
flashes the taskbar, LEAVE IT AT THAT.  That's what the user has decided 
he wants.

[04:10]	kostix	jenglish: what about me being the user? I can understand 
this "polite" thing, it's probably good in terms of HID guidelines but 
when I click the tray icon I'm making a conscious gesture, right?

[04:11]	jenglish	If you, as a user, don't like that behavior, change 
your WM settings.  Or use a different WM.

[04:12]	jenglish	If you, as a program author, don't like that behavior, 
STOP FIGHTING IT.  Because Lubos will always win in the end.

[04:16]	kostix	ok, thanks jenglish

[04:17]	jenglish	In the meantime, Tk really ought to support 
_NET_WM_DEMANDS_ATTENTION.  There's an FR open for that, undealt with to 
date.

[04:21]	stu	Lubos ?

[04:21]	jenglish	Lubos Lunak.  Author of KWIN, the KDE window manager.

[04:22]	jenglish	Inventor of "focus-stealing prevention" mechanisms and 
_NET_WM_DEMANDS_ATTENTION.
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Hope this helps.