[Xmonad] help with layout modifiers

[Andrea Rossato]

On Wed, Aug 29, 2007 at 10:27:48AM -0400, David Roundy wrote:
> Your doLay is buggy:  when dl returns a modified layout, your mouseFocus
> "falls off".  Similarly with ml.  I would use LayoutHelpers:
> 
> mouseFocus = layoutModifer idModDo modLay
>   where modLay sm | Just e <- fromMessage sm = handle_event e >> return Nothing
>         handle_event e@(CrossingEvent {ev_window = w, ev_event_type = t})
>                | t == enterNotify && ev_mode   e == notifyNormal
>                                   && ev_detail e /= notifyInferior
>                    = focus w -- what should I do to XState after this?
>         handle_event _ = return ()

This was my first attempt, actually, but it doesn't work as expected.
For instance, if I use it with DragPane, doClick (mouse dragging)
stops working. Moreover if I use mod-l or mod-h to resize the panes,
and after that I change the focus with the mouse - which works as
expected, as in the previous code -, the decorations will not be
destroyed anymore if I resize once again. The same with Tabbed.

In other words, Decoration stops working correctly. 

The problem is that this code produces the very same issue as the one
I submitted before. I would like to understand where I'm doing
something wrong.

Thanks for your kind attention.

Andrea