Is it possible to define a property with Class type that conforms to protocol?

Question

For example, I have MyFancyData protocol. How can I specify that MyFancyDataClass property accepts only classes that conforms to this protocol.

@interface MyObject : NSObject

@property Class MyFancyDataClass;

Answer 1

Do you mean something like this?

@interface MyObject : NSObject

@property (nonatomic, assign) Class<MyFancyData> cls;
@end

Answer 2

@property id<MyFancyData> myFancyDataClass;