The callback function principle of Python

__getattribute__ effect

""" class C (object):    a = ' abc '    def __getattribute__ (self, *args, **kwargs):        print ("__getattribute__ () is Called ")        print args        if args[0] = = ' A ':            return object.__getattribute__ (self, *args, **kwargs)        else:            print ' Call function foo () '            return object.__getattribute__ (self, ' foo ') ()    def foo (self):        return "Hello" if __name__ = = ' __main__ ':    c = C ()    print C.foo"" "

Callback

classCallback:def __init__(self, instance, function_name): Self.instance= Instance#api.selfSelf.function_name = Function_name#function    defaction (self, params):PrintSelf.instance.__getattribute__(Self.function_name) self.instance.__getattribute__(Self.function_name) (params)classTest:def __init__(self): SELF.CLB=Nonedefregister (self, CLB): SELF.CLB= CLB#Callback (self, self.function.__name__)    defdo_test (self): params=[] self.clb.action (params)classApi (object):def __init__(self, test_instance): Test_instance.register (Callback (self, self.function.__name__))    deffunction (self, params):PrintparamsPrint('function') T=Test () a=Api (t) t.do_test ()

The callback function principle of Python