Waiting block to finish is possible?

Question

Is it possible to wait some Server Query block to end its operation? My unworking code is below;

 + (BOOL) loginQueryFromServer:(NSDictionary *)parameters{

  __block BOOL loginQueryResult = NO;

  AFHTTPRequestOperationManager *manager = [AFHTTPRequestOperationManager manager];

  AFHTTPRequestOperation *operation = [manager POST:@"http://domainname/login/" parameters:parameters success:^(AFHTTPRequestOperation *operation, id responseObject) {

    NSLog(@"Response1: %@",responseObject);
    loginQueryResult = YES;
    NSLog(@"Response2: %@", loginQueryResult ? @"YES" : @"NO");
  } failure:^(AFHTTPRequestOperation *operation, NSError *error) {

    NSLog(@"Error: %@", error);
    loginQueryResult = NO;
  }];
  [operation start];
  [operation waitUntilFinished];

  NSLog(@"Response3: %@", loginQueryResult ? @"YES" : @"NO");
  return loginQueryResult;
}

Result: (As you can see; Response3 logs first)

2014-04-09 21:11:17.072 aaa[1010:70b] Response3: NO
2014-04-09 21:11:17.073 aaa[1010:70b] Response1: {
    reply = "Login successful!";
}
2014-04-09 21:11:17.081 aaa[1010:70b] Response2: YES

Answer 1

I know this doesn't exactly answer the question - but I would suggest you rewrite your loginQueryFromServer: method to accept a completion block itself so that it is asynchronous (I think this is ultimately what you are trying to do):

+ (void) loginQueryFromServer:(NSDictionary *)parameters completion:(void(^)(BOOL response, NSError *error))completionBlock {

    AFHTTPRequestOperationManager *manager = [AFHTTPRequestOperationManager manager];

    AFHTTPRequestOperation *operation = [manager POST:@"http://domainname/login/" parameters:parameters success:^(AFHTTPRequestOperation *operation, id responseObject) {

        completionBlock(YES, nil);

    } failure:^(AFHTTPRequestOperation *operation, NSError *error) {

        completionBlock(NO, error);
    }];
    [operation start];
} 

Use it like this:

[YourClass loginQueryFromServer:someDictionary completion:^(BOOL response, NSError *error) {

    // do something with the response and the error if it exists
}];

Answer 2

You're using the third-party AFNetworking library. So the question is: did the developers of that want you to be able to do something when an operation is finished?

The answer is yes:

The built-in completionBlock provided by NSOperation allows for custom behavior to be executed after the request finishes.

The class you're using is a subclass of NSOperation. So assign a block to its completionBlock property.