Are AFNetworking success/failure blocks invoked on the main thread?

Question

Does AFNetworking call the completion block on the main thread? or is it called in the background, requiring me to manually dispatch my UI updates to the main thread?

Using code instead of words, this is the example code from the AFNetworking documentation with the call to NSLog replaced by a UI update:

AFJSONRequestOperation *operation = [AFJSONRequestOperation JSONRequestOperationWithRequest:request success:^(NSURLRequest *request, NSHTTPURLResponse *response, id JSON) {
    self.label.text = JSON[@"text"];
} failure:nil];

Should it be written like this instead?

AFJSONRequestOperation *operation = [AFJSONRequestOperation JSONRequestOperationWithRequest:request success:^(NSURLRequest *request, NSHTTPURLResponse *response, id JSON) {
    dispatch_async(dispatch_get_main_queue(), ^{
        self.label.text = JSON[@"text"];
    });
} failure:nil];

@tdarr all the source code are available, take a look and you can know it all — onmyway133, Jul 06 '14 at 18:04

score 43 · Answer 1 · answered Jun 20 '13 at 23:03

They are invoked on the main queue, unless you explictly sets the queue on AFHTTPRequestOperation, as shown in setCompletionBlockWithSuccess:failure from AFHTTPRequestOperation.m

self.completionBlock = ^{
    if (self.error) {
        if (failure) {
            dispatch_async(self.failureCallbackQueue ?: dispatch_get_main_queue(), ^{
                failure(self, self.error);
            });
        }
    } else {
        if (success) {
            dispatch_async(self.successCallbackQueue ?: dispatch_get_main_queue(), ^{
                success(self, self.responseData);
            });
        }
    }
};

Good to know probably should have checked and not assumed they just executed them on the same thread as the request — Ben Coffman, Jun 20 '13 at 23:17

onmyway133 · Accepted Answer · 2016-03-16T09:30:11.723

32

In AFNetworking 2, AFHTTPRequestOperationManager has a completionQueue property.

The dispatch queue for the completionBlock of request operations. If NULL (default), the main queue is used.

    #if OS_OBJECT_USE_OBJC
    @property (nonatomic, strong, nullable) dispatch_queue_t completionQueue;
    #else
    @property (nonatomic, assign, nullable) dispatch_queue_t completionQueue;
    #endif

In AFNetworking 3, the completionQueue property has been moved to AFURLSessionManager (which AFHTTPSessionManager extends).

The dispatch queue for completionBlock. If NULL (default), the main queue is used.

@property (nonatomic, strong) dispatch_queue_t completionQueue;
@property (nonatomic, strong, nullable) dispatch_queue_t completionQueue;

edited Mar 16 '16 at 09:30

answered Jul 02 '14 at 08:36

onmyway133

45,645
31
257
263

I agree! I edited the answer to include AFNetworking 3 and to add links to the source of both versions. – thomasd Mar 15 '16 at 18:14
@thomasd thanks. There are some rejections on your edit, so I can't accept it, but I just copied it again. – onmyway133 Mar 16 '16 at 09:30

OhadM · Answer 3 · 2016-04-19T09:38:24.130

As everyone explained, it's in the source code of the AFNetworking, as for the way to do it,

AFNetworking 2.xx:

// Create dispatch_queue_t with your name and DISPATCH_QUEUE_SERIAL as for the flag
dispatch_queue_t myQueue = dispatch_queue_create("com.CompanyName.AppName.methodTest", DISPATCH_QUEUE_SERIAL);

// init AFHTTPRequestOperation of AFNetworking
operation = [[AFHTTPRequestOperation alloc] initWithRequest:request];

// Set the FMDB property to run off the main thread
[operation setCompletionQueue:myQueue];

AFNetworking 3.xx:

AFHTTPSessionManager *manager = [[AFHTTPSessionManager alloc] init];
[self setCompletionQueue:myQueue];

score 1 · Answer 4 · answered Dec 20 '13 at 06:36

1

You can set the completion callback queue by specifying completionGroup, completionQueue see the AFNetworking API document

answered Dec 20 '13 at 06:36

Elaine

1,288
5
17
35

Are AFNetworking success/failure blocks invoked on the main thread?

4 Answers4

Linked