Objective-c delegate

Delegate.h

@protocol MyControlDelegate;

@interface MyControl : NSObject

@property (nonatomic, weak) id<MyControlDelegate> delegate;

- (id)initWithDelegate:(id<MyControlDelegate>)aDelegate;
+ (id)objectWithDelegate:(id<MyControlDelegate>)aDelegate;

@end

@protocol MyControlDelegate <NSObject>

@optional
- (void)delegateAction:(id)value;

@end

Delegate.m

@implementation MyControl

- (id)initWithDelegate:(id<MyControlDelegate>)delegate{
    if((self = [super init])){
        self.delegate = delegate;
    }
    return self;
}

+ (id)objectWithDelegate:(id<MyControlDelegate>)delegate{
    return [[[self class] alloc] initWithDelegate:delegate];
}

- (void)action{
    if([self.delegate respondsToSelector:@selector(delegateAction:)]){
        [self.delegate delegateAction];
    }
}

@end