Everytime I call my function def hello(self,value) I get an error : takes exactly 2 arguments (1 given) so what could I do ?

Or is there another possibility to do this: self.statusitem.setImage_(self.iconsuccess)?

EDIT:

simple representation of my code

Class A:func_in_class_B(value)Class B:
def finishLaunching(self):self.statusitem.setImage_(self.icon)
def func_in_class_B(self,value)self.statusitem.setImage_(self.iconsuccess)

Class A is a background thread and Class B my main thread, and I want to manipulate `self.statusitem.setImage_(self.icon)

It sounds like you aren't calling your hello function correctly. Given the following class definition:

class Widget(object):def hello(self, value):print("hello: " + str(value))

You are probably calling it like a static function like this:

Widget.hello(10)

Which means no instance of a widget class gets passed as a first param. You need to either set up the hello function to be static:

class Widget(object):@staticmethoddef hello(value):print("hello: " + str(value))Widget.hello(10)

or call it on a specific object like this:

widget = Widget()
widget.hello(10)