what does Protocol* x = @protocol(aProtocolName) do in objective c?

Question

I found that I could do such things in objc:

Protocol* aProtocol = @protocol(NSObject);

but what is this technique used for?

To do this: http://stackoverflow.com/questions/3436257/objective-c-runtime-best-way-to-check-if-class-conforms-to-protocol — kennytm, Nov 17 '11 at 10:45

score 0 · Accepted Answer · answered Nov 17 '11 at 11:06

0

You could have, for example, a container that offers a service to check that all of its contents conform to a protocol.

Protocol *contentProtocol;

- (void)setContentProtocol:(Protocol *)proto;

Then the user of the container could call:

[container setContentProtocol:@protocol(MyProtocol)];

And somewhere in the container the check could be made:

[[item class] conformsToProtocol:contentProtocol];

answered Nov 17 '11 at 11:06

Arkku

or just `[item conformsToProtocol:contentProtocol]` – user102008 Jul 18 '12 at 20:55

score 0 · Answer 2 · edited May 23 '17 at 12:11

0

what is use of Formal Protocol Object
You can use it to check if an object conforms to a protocol.

[anotherObject conformsToProtocol:aProtocol];

edited May 23 '17 at 12:11

Community

answered Nov 17 '11 at 12:02

Parag Bafna

2 Answers2