[Zope-dev] z3c.form - extraction from sequence widget

[Martin Aspeli]

Marius Gedminas wrote:
> On Wed, Aug 27, 2008 at 05:15:48PM -0700, Stephan Richter wrote:
>> On Wednesday 27 August 2008, Martin Aspeli wrote:
>>> This means that if the request contains the empty-marker only (no
>>> selection was made) for a checkbox widget (say), then the return value
>>> is [], rather than default (NOVALUE).
>>>
>>> Is that a bug? I have a custom checkbox widget derived from the standard
>>> checkbox widget, (z3c.formwidget.query, in fact), and I never get any
>>> "required missing" exceptions, even when I untick all the checkboxes and
>>> click OK.
>>>
>>> Am I missing something?
>> I think you have a point. Have you tried changing the behavior to 
>> return "default" and see what tests fail? If no major failures come out of 
>> this, I would say change it.
> 
> Wait a second, maybe I'm misunderstanding this, but I certainly oppose
> any change that would make an unchecked checkbox an error during form
> validation.
> 
> A required Bool field can have two values: True or False.  One is
> represented by a checked checkbox, the other by an unchecked checkbox.
> An unchecked checkbox is not missing input and should not trigger
> "required missing" errors.

What about the case when you have a list of options of which you need to 
chose one or more? In that case, ticking none is a validation error.

Martin


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