It seems that your "Window" class in ui.py differs a bit from mine, you don't have the method "SetMouseLeftButtonUpEvent", edit the "Window" class as following :
class Window(object):
[...]
def __init__(self, layer = "UI"):
[...]
self.mouseLeftButtonDownEvent = None
self.mouseLeftButtonDownArgs = None
self.mouseLeftButtonUpEvent = None
self.mouseLeftButtonUpArgs = None
[...]
def SetMouseLeftButtonDownEvent(self, event, *args):
self.mouseLeftButtonDownEvent = event
self.mouseLeftButtonDownArgs = args
def OnMouseLeftButtonDown(self):
if self.mouseLeftButtonDownEvent:
apply(self.mouseLeftButtonDownEvent, self.mouseLeftButtonDownArgs)
def SetMouseLeftButtonUpEvent(self, event, *args):
self.mouseLeftButtonUpEvent = event
self.mouseLeftButtonUpArgs = args
def OnMouseLeftButtonUp(self):
if self.mouseLeftButtonUpEvent:
apply(self.mouseLeftButtonUpEvent, self.mouseLeftButtonUpArgs)