ScriptRunner Behaviour - find changed checkbox

[Steve Kamens]

I have a behavior with checkboxes that includes values

None

Value 1

Value 2

Value 3

I want to clear all the values if "None" is clicked which I have been able to do.

But I also want to clear "None" if any value is clicked, which I have not been able to do.

While I can retrieve all the selections, I can't get which checkbox was clicked, so I don't know if the user just clicked "None" or just clicked a Value

Is there a way to know what values were before the click or to know which specific checkbox was clicked?  Or any other thoughts on how to achieve this?