NSUrlConnection When Locking the Screen?

Question

I tried several ways to execute NSURLConnection while locking the screen, but none of this works.

I tried the following:

[self performSelectorInBackground:@selector(startConnection) withObject:nil]; 

I also tried:

 dispatch_queue_t request_queue = dispatch_queue_create("com.app.download", NULL); dispatch_async(request_queue, ^{ [self startConnection]; }); 

in startConnection:

 - (void)startConnection{ ... some URL processing responseData_ = [[NSMutableData alloc] init]; connection_ = [[NSURLConnection alloc] initWithRequest:urlRequest delegate:self]; } 

NSURLConnection delegate methods are not called in this way. What is the real code to make it work? Thanks!

A small update that may help :

It only calls this delegate method:

 - (void)connection:(NSURLConnection *)connection didFailWithError:(NSError *)error 

with the message:

Could not find a server with the specified host name.

I am very sure that my Wi-Fi is connected, still not sure why it is called: (

Answer 1

If you lock the screen, your application will turn into a background mode, the background mode does not work. If you want to load when the user locks the screen, you should check this method [UIApplication -beginBackgroundTaskWithExpirationHandler:]