[Urwid] Strange behaviour of ListBox

[Ian Ward]

jm at jm10.no-ip.com wrote:

> I don't want the body to lose the focus (once at the bottom at the body, the top
> listbox selects another widget on 'down') and I don't know how to solve that.
> Your answer seems to say it is possible... maybe like that (not yet committed) :
> 
> http://hachoir.python-hosting.com/file/hachoir/trunk/src/hachoir/ui/urwid/urwid_ui.py
> --- src/hachoir/ui/urwid/urwid_ui.py    (revision 449)
> +++ src/hachoir/ui/urwid/urwid_ui.py    (working copy)
> @@ -408,2 +408,3 @@
>      log = BoxAdapter(ListBox(msgs[1]), 0)
> +    log.selectable = lambda: False
>      top = ListBox((body, AttrWrap(sep, 'sep'), log))
> @@ -438,3 +439,3 @@
>                      else:
> -                        body.keypress(size[:1], e)
> +                        top.keypress(size, e)
>                  except AssertionError:

That works.  You could also use:
     log = BoxAdapter(ListBox(msgs[1]), 0)
     foot = urwid.Pile([ AttrWrap(sep, 'sep'), log ])
     top = Frame( body, footer = foot )

because a Frame won't change focus away from body unless you tell it to. 
  But if you support mouse events someone might still click to change 
the focus, so you could use your lamba trick on "foot".

Another way to say "this widget should never be selectable" is to use 
WidgetWrap:
     class NeverSelectable(urwid.WidgetWrap):
         def selectable(self):
             return False
     foot = NeverSelectable(foot)


Ian