Can functions be called on click of custom buttons in stateless forms??

I have:

input.note_field = thisapp.function(input.field1,input.field2) and nothing happens, but this very function runs on user input of any other field in the form. I've tried something very simple on click of same button, like input.field = "test"; and still nothing happens. BUT, alert "this is an alert"; DOES work. What's up w/ stateless form buttons??