method call between different class in Objective c

Question

Is it possible to call method from one class to another where two classes from two different parent class. Suppose one from UIImage class and another from UIViewController class?

Answer 1

Yes, one of the cool things about Objective-C is that you can call a method on any object, even if it doesn't respond. Although not as robust as in Objective-C's father, SmallTalk (yes, SmallTalk is the dad and C is the mom, don't ask), it's still pretty powerful. So let's say you have something like this:

- (void)doSomethingToThis: (id)thisObject
{
  [thisObject doSomething];
}

Then later...

//...
  UIImage *thisImage = ...
  UIViewController *thisController = ...

  [self doSomethingToThis: thisImage];
  [self doSomethingToThis: thisController];
//...

Something like this will compile just fine, but be warned if UIImage and UIViewController don't both respond to doSomething, then you could end up with a crasher (depends on how you have the compiler flags set, but I believe by default you'll get a crash).

Answer 2

You probably want to do something like what is said in this answer of another question:

Objective-C : Call a method from another class in addTarget:action:forControlEvents