[xmonad] Tabbed.addTabs broken?

[Andrea Rossato]

On Tue, Feb 12, 2008 at 06:17:55PM -0500, David Roundy wrote:
> > This one breaks Tabbed.addTabs:
> 
> How does it do so? What happens that is wrong?

My use of the word "broken" is confusing. Sorry for that. Nothing
wrong is happening. What I meant is that addTabs is going to work
*only* with Simplest at the present time, because Simplest is the only
one in which 2 windows may be stacked.

> 
> > Tue Feb  5 21:23:43 CET 2008  David Roundy <droundy at darcs.net>
> >   * make tabbed work nicely with LayoutCombinators and WindowNavigation.
> >   The problem is that WindowNavigation assumes all windows are navigable, and
> >   it was getting confused by decorations.  With a bit of work, we can
> >   decorate windows *after* combining layouts just fine.
> 
> I'm not clear what the problem is here.  The theory of addTabbed was that
> the tabbed decoration should be able to decorate a "mixed" layout, in which
> some of the windows are supposed to be tabbed, and others are not (and
> those don't get decorated).  If it doesn't do this, then yes, it's broken.

It does so, and so it is not broken. My fault, since I thought it was
just more general, and could be used for, say, Circle, or Mirror
tiled.

At first Layout.Tabbed.hs was exporting a style that could be used
with any layout, not just with layouts with stacked windows.

> > It also assumes the decoration to have the same y coordinate of the
> > window to be decorated - the window must be shrunk. That is to say, if
> > we were to remove the first constraint, we would end up with a
> > SimpleDecoration layout modifier. :)
> 
> I'm a little unclear here:  what is it that you want tabbed to do? I had to
> make this change (I think) in order to make tabbed work properly when it is
> placed in a subset of the screen.  Your tabbed was trying to draw the tabs
> at the top of the screen regardless, as I recall.  Certainly we must use
> the locations of the windows to determine the locations of the tabs,
> otherwise everythings going to look crazy.

Now I think I get exactly the problem your patch was trying to solve.
What I want is to have a tabbed-like (let's call it this way) that can
be used with any layout.

For instance, a tabbed-like decoration that works with a floating
layout:
http://code.haskell.org/~arossato/xmonadShots/floatSimpleTabbed.png

(Actually I'm not using such a layout, but I had a request for
something like this).

What I was asking was that:

1. can I change Layout.Tabbed.TabbedDecoration so that something like
   this can be done with that style without breaking WindowNavigation
   - and possibly other things? If yes, do I need to change
   WidowNavigation? If this is another yes, how?

2. Suppose that Layout.Tabbed.TabbedDecoration is not to be changed
   (because we need a style like that in order to get a properly
   working (real) tabbed layout). Now, if I write a
   TabbedLikeDecoration style, which will place decorations on the top
   of the screen, is that going to break WindowNavigation? May I
   change WindowNavigation to allow such a style to be used with it?

(Note that I followed option 2. for DecorationMadness, but without
exporting this TabbedLikeDecoration style).

> 
> > But, as far as I understand, this is needed for WindowNavigation (I do
> > not understand well its code, and I didn't have time to study it).
> 
> No, this bit is no longer needed for WindowNavigation.  It is, however,
> needed if you want to apply this decoration to a more interesting layout
> than Simplest.  (Which was required by WindowNavigation, prior to the patch
> mentioned below.)  I do think this is a good idea, as it gives us a more
> composable interface (i.e. we could combine layouts *prior* to adding
> decorations, which might have advantages).

This means that both option 1 and option 2 would work fine with
WindowNavigation, without any change?

> It's better *not* to use isDecoration, on the principle that we should be
> checking for the actual property that we require (presense in the stack),
> not for a different property that happens to be true for the same windows.

This is an interesting point. Probably I should just change
isDecoration to use the stack, right?

> I haven't upgraded my xmonad since I wrote these patches, and doubt I'll
> upgrade any time soon (there's always the possibility when upgrading that
> I'll lose a half-day of work getting thing going again like they were
> before...), but my feeling is that tabbed and WindowNavigation aren't very
> broken (unless they've gotten more broken).

I hope I clarified that both tabbed and WindowNavigation are *not*
broken. But I don't want to break them with the style I need (the
TabbedLikeDecoration style)

Thanks for you help.

Andrea