Question

In Objective-C, can we have a class Foo and a class Bar, and then do something like

Class aClass = [Foo class];
[aClass getURLString];

where getURLString is a class method of the class Foo or Bar. So in other words, invoke different class methods based on the class, and this class is referenced by a variable.

Foo and Bar have the same base class of NSObject in this example. I tried using the code above and it won’t work. If I use

id aClass = Foo;

or

id aClass = [Foo class];

It won’t work either. Must I instantiate a dummy object? Can Objective-C do it without instantiation?

Answer 1

What you’re trying should work fine. For example, the following works:

Class NSStringClass = [NSString class];
NSString *string = [NSStringClass string];

Is it possible you’ve neglected to #import the definition of Foo?