Simple example of delegate callbacks from an AFHTTPClient subclass instantiated as a singleton.

exampleForTim

//
//  TAHAppNetClient.h
//  Net
//
//  Created by Tom Hutchinson on 15/06/2013.
//  Copyright (c) 2013 Tom Hutchinson. All rights reserved.
//

#import "AFHTTPClient.h"

@protocol TAHAppNetClientDelegate;

@interface TAHAppNetClient : AFHTTPClient

@property(weak) id<TAHAppNetClientDelegate> delegate;

+ (TAHAppNetClient *)sharedTAHAppNetClient;
- (id)initWithBaseURL:(NSURL *)url;

@end

@protocol TAHAppNetClientDelegate <NSObject>
-(void)appNetClient:(TAHAppNetClient *)client didUpdateWithPosts:(id)posts;
-(void)appNetClient:(TAHAppNetClient *)client didFailWithError:(NSError *)error;

@end


//
//  TAHAppNetClient.m
//  Net
//
//  Created by Tom Hutchinson on 15/06/2013.
//  Copyright (c) 2013 Tom Hutchinson. All rights reserved.
//

#import "TAHAppNetClient.h"

@implementation TAHAppNetClient

+ (TAHAppNetClient *)sharedTAHAppNetClient {
	NSString *baseURLString = @"https://alpha-api.app.net/";

	static dispatch_once_t pred;
	static TAHAppNetClient *_sharedTAHAppNetClient = nil;

	dispatch_once(&pred, ^{ _sharedTAHAppNetClient = [[self alloc] initWithBaseURL:[NSURL URLWithString:baseURLString]]; });
	return _sharedTAHAppNetClient;
}

- (id)initWithBaseURL:(NSURL *)url {
	self = [super initWithBaseURL:url];
	if (!self) {
		return nil;
	}

	[self registerHTTPOperationClass:[AFJSONRequestOperation class]];

	[self setDefaultHeader:@"Accept" value:@"application/json"];

	return self;
}

-(void)updatePosts {    
	[self getPath:@"stream/0/posts/stream/global"
	   parameters:nil
		  success:^(AFHTTPRequestOperation *operation, id responseObject) {
			  NSArray *posts = [responseObject objectForKey:@"data"];
			  for (id thisPost in posts) {
				 //Parse Posts
			  }


			  if([self.delegate respondsToSelector:@selector(appNetClient:didUpdateWithPosts:)])
				  [self.delegate appNetClient:self didUpdateWithPosts:responseObject];

		  }
		  failure:^(AFHTTPRequestOperation *operation, NSError *error) {
			  if([self.delegate respondsToSelector:@selector(appNetClient:didFailWithError:)])
				  [self.delegate appNetClient:self didFailWithError:error];
		  }];
}
@end