class Form.Element.Observer
Description
An Abstract.TimedObserver
subclass that watches for changes to a form
field's value. This triggers the callback when the form field's value
(according to Form.Element.getValue
) changes. (Note that when the value
actually changes can vary from browser to browser, particularly with
select
boxes.)
Form.Element observer implements the getValue()
method using
Form.Element.getValue
on the given element. See Abstract.TimedObserver
for general documentation on timed observers.