Save Date in server when user press home button

Question

I want to save all the data used in app in server (using API call) when user touch home button. I set the observer as

[[NSNotificationCenter defaultCenter]  addObserver:self selector:@selector(saveData) name:UIApplicationDidEnterBackgroundNotification object:nil];

the saveData method is used to send the data to server. The api call is not worked. Any way to call API when user close the app.

Answer 1

I've started the background task as

- (void)applicationDidEnterBackground:(UIApplication *)application
{


      bgTask = [application beginBackgroundTaskWithName:@"MyTask" expirationHandler:^{

[self saveData];
            // Clean up any unfinished task business by marking where you
            // stopped or ending the task outright.

        }];

    // Start the long-running task and return immediately.
    dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{

        // Do the work associated with the task, preferably in chunks.

        [application endBackgroundTask:bgTask];
        bgTask = UIBackgroundTaskInvalid;
    });
}

And then added the below line inside the saveData method

 [application endBackgroundTask:bgTask];
            bgTask = UIBackgroundTaskInvalid;