Objective-C Pointer to class that implements a protocol
- by Winder
I have three classes which implement the same protocol, and have the same parent class which doesn't implement the protocol. Normally I would have the protocol as pure virtual functions in the parent class but I couldn't find an Objective-C way to do that.
How can I utilize polymorphism on these subclasses and call the functions implemented in the protocol without warnings?
Some pseudocode if that didn't make sense:
@interface superclass: NSObject
{}
@interface child1: superclass<MyProtocol>
{}
@interface child2: superclass<MyProtocol>
{}
The consumer of these classes:
@class child1
@class child2
@class superclass
@interface SomeViewController: UIViewController
{
child1 *oneView;
child2 *otherView;
superclass *currentView;
}
-(void) someMethod
{
[currentView protocolFunction];
}
The only nice way I've found to do pure virtual functions in Objective-C is a hack by putting [self doesNotRecognizeSelector:_cmd]; in the parent class, but it isn't ideal.
