justinfrench/formtastic — pull request #991 by maximchick (2014-01-26 16:16:44+00:00)
Title: Sometimes you need to invert boolean field so you need to use 0 as a che...

Sometimes you need to invert meaning of boolean attribute on a form, for example display model.enabled attribute as "Disable" checkbox. To do this you need to invert the meaning of an attribute. You can do it by setting

checked_value: 0, unchecked_value: 1

but unfortunately current version of formtastic would not work becaus 0 is hardcoded in boolean_checked? method for integer values.