[flexcoders] How do I Change Event on a CheckBox

[Mark]

I'd like to run a function whenever a checkbox has changed regardless if the 
user selects/deselects it or if it changes from a different user action (such 
as resetting filters by clicking a button).  I tried using 
calendarCheckbox.addEventListener(Event.CHANGE, changeCBF); but this only works 
from a user interacting with that checkbox.  How can I do this?

Thanks,
Mark