Checking to see if an optional protocol method has been implemented

Question

Hey there,

Does anyone know the best way to check to see if an optional protocol method has been implemented.

I tried this:

if ([self.delegate respondsToSelector:@selector(optionalProtocolMethod:)] )

where delegate is:

id<MyProtocol> delegate;

However - I get an error saying that the function respondsToSelector is not found in the protocol!

Thanks for any help! Cheers, Nick.

Answer 1

respondsToSelector: is part of the NSObject protocol. Including NSObject in MyProtocol should solve your problem:

@protocol MyProtocol <NSObject>

@optional
-(void)optionalProtocolMethod:(id)anObject;

@end