Load json data in lazy loading manner in iphone

- (void)loadDataSource {
    // Request
    NSString *URLPath = [NSString stringWithFormat:@"http://imgur.com/gallery.json"];
    NSURL *URL = [NSURL URLWithString:URLPath];
    NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:URL];
   
    [NSURLConnection sendAsynchronousRequest:request queue:[NSOperationQueue mainQueue] completionHandler:^(NSURLResponse *response, NSData *data, NSError *error) {
       
        NSInteger responseCode = [(NSHTTPURLResponse *)response statusCode];
       
        if (!error && responseCode == 200) {
            id res = [NSJSONSerialization JSONObjectWithData:data options:NSJSONReadingMutableContainers error:nil];
            if (res && [res isKindOfClass:[NSDictionary class]]) {
                self.items = [res objectForKey:@"gallery"];
                [self dataSourceDidLoad];
            } else {
                [self dataSourceDidError];
            }
        } else {
            [self dataSourceDidError];
        }
    }];
}