Basic pub/sub with Objective-C

Publisher.h

@interface Publisher : NSObject

- (void)subscribe:(void(^)(id object))subscriptionBlock;

- (void)publish:(id)object;

@end

Publisher.m

#import @"Pubslisher.h"

@interface Publisher ()

// Mutable array to hold subscription blocks
@property (nonatomic, strong) NSMutableArray *subscriptionBlocks;

@end

@implementation Publisher

- (id)init {
    self = [super init];
    if (self) {
        self.subscriptionBlocks = [@[] mutableCopy];    
    }
    return self;
}

- (void)subscribe:(void(^)(id object))subscriptionBlock {
    [self.subscriptionBlocks addObject:subscriptionBlock];
}

- (void)publish:(id)object {

    [self.subscriptionBlocks enumerateObjectsUsingBlock:^(void(^subscriptionBlock)(id object), NSUInteger index, BOOL *stop) {
        subscriptionBlock(object);
    }];
}

@end

Subscriber.h

#import "Pubslisher.h"

@interface Subscriber : NSObject

@property (nonatomic, strong) Pubslisher *pubslisher;

@end

Subscriber.m

#import "Subscriber.h"

@implementation Subscriber 

- (void)setPublisher:(Publisher *)publisher {
    _pubslisher = publisher;

    // Subscribe to publisher
    [_publisher subscribe: ^ (id object) {

        // Called every time publish: is called upon _publisher
        NSLog(@"%@", object);

    }];
}

@end

can you please explain how to use?

@Gagan5278: Take a few minutes to read through the code. I'm not an Objective C expert and it looks very straightforward to me.