Objective C - How to use OC Mock?

I hav开发者_Python百科e a class that suppose to return a string when a method gets called. How can i create a mock object.

I want mock to return @"Hello" when the method "sayHello" get's called

id mock = [OCMockObject mockForClass:[MyCrazyClass class]];

[[[mock stub] andReturn:@"Hello"] yourMethod:someArgument];