[farshizzo]

You need to assign the return value of the createButton function to a variable:

import viz
import button

viz.go()


btn = button.Button()

testbutton = btn.createButton([0.2,0.5], 'testbutton')

def onButton(obj,state):
	if obj == testbutton:
		print 'test'

viz.callback(viz.BUTTON_EVENT,onButton)