[Urwid] Resizing windows in urwid: how small is too small?

[Ian Ward]

James Reeves wrote:
> Ian Ward wrote:
>> I think that's a great idea.  Florian Festi mentioned a similar 
>> discomfort with the way Columns and Piles align widgets, but suggested 
>> adding alignment attributes to the widgets as a solution.  I like your 
>> approach better because it lends itself more to Urwid's style of 
>> widget-reuse and small, simple widget classes.
>>
>> I look forward to your patch :-)
>>   

> I've adapted the Columns and Pile widgets to work with the layout hint 
> wrappers. The code is essentially mostly unchanged; I just replaced all 
> of the tuple-handling code with isinstance checks, etc. I also updated 
> the unit tests in test_urwid.py.
> 
> I'm undecided on the syntax, but it seems reasonable.
> 
> What are your thoughts?

It looks pretty good, but I wonder if there is a way to do it in a more 
duck-typing style.

Instead of isinstance() perhaps we could check for a size_hint attribute 
and use it if it's there. That way people that know they are only using 
"my_widget" in one container could just do something like:
   my_widget.size_hint = 'weight'
   my_widget.size_hint_weight = 5

I would prefer to name the classes FlowHint, WeightHint and FixedHint 
and make them part of the urwid namespace (not a separate submodule), so 
the same thing as above without modifying my_widget would be:
   my_hinted_widget = urwid.WeightHint(my_widget, 5)

The hint classes could inherit from a new base class I'm planning to add 
"DecoratorWidget".  See: http://excess.org/urwid/wiki/NewBaseClasses

Ian