[Xmonad] darcs patch: add decorations infrastructure

[Donald Bruce Stewart]

sjanssen:
> On Sat, 09 Jun 2007 12:27:00 -0700
> David Roundy <droundy at darcs.net> wrote:
> 
> > Hi all,
> > 
> > Here's some infrastructure to allow layouts to define window
> > decorations such as tabs or title bars.  I'm mostly sending it in to
> > get comments. I soon hope to have a crude tabbed layout using this.
> > 
> > David
> > 
> > Sat Jun  9 12:23:49 PDT 2007  David Roundy <droundy at darcs.net>
> >   * add decorations infrastructure
> > 
> 
> I think we should leverage the existing layout/message system as much
> as possible here.  Proposed modifications:
>  - instance Message XEvent

Good.

>  - dispatch unhandled XEvents to layouts

Good.

>  - add another message type: data ViewMsg = View | Hide -- send this
>  message to layouts on workspace change

Ok, what's the case here? that a layout has drawn something on the
screen depending on the workspace, and won't know that its moved to a
new workspace?

Perhaps doLayout should take (Stack a, WorkspaceId) ?

>  - put modifyLayout in the X monad

Seems reasonable.
  
> This should give us enough flexibility to do decorations inside layouts
> without polluting the core with decoration handling.

Souds good.

-- Don