Question

this is how I start a background task when application goes background ,

   void applicationDidEnterBackground:(UIApplication *)application
{
    btId = UIBackgroundTaskInvalid;
    UIApplication* cuiApplication = [UIApplication sharedApplication];

    void (^backgroundTimeRemainingExtenderHandler)() = ^() {

        NSTimeInterval timeRemaining1 = [cuiApplication backgroundTimeRemaining];

        if(btId != UIBackgroundTaskInvalid){
            [proximityEngine StopEngine];
            [cuiApplication endBackgroundTask:btId];
            btId = UIBackgroundTaskInvalid;
        }
    };

    btId= [cuiApplication beginBackgroundTaskWithExpirationHandler:backgroundTimeRemainingExtenderHandler];

    if(bgmanager != nil){
        [bgmanager BeginBackgroundTaskMainLoop];
    } 
}

My problem is that when my background task calls :

NSURLConnection sendSynchronousRequest

The expiration block is being called even though there is more time remaning , how can I prevent this ?

Regards ,

James

EDIT :

After reading the answer below : I still have 596 seconds left when querying the amount of time left and yet still IOS calls the expiration block handler.

Answer 1

In my particular case – which I do not quite sure why it behaved the way it behaved , I performed the task on a different thread than the beginbackgroundtask thread , after sendsync returned in that thread the backgroundtask was interrupted by the OS .
When calling sendsync in the beginbackground original thread , it does not occur.
Not sure if its something logical and I did something wrong or an OS bug.