IOs7 app crashing when in background
- by Leonardo
My app sometimes crashes when in background and shows the following crash log:
Nov 7 12:33:31 iPad backboardd[29] <Warning>: MyApp[3096] has active assertions beyond permitted time:
{(
<BKProcessAssertion: 0x14680c60> identifier: Called by MyApp, from -[AppDelegate applicationDidEnterBackground:] process: MyApp[3096] permittedBackgroundDuration: 180.000000 reason: finishTask owner pid:3096 preventSuspend preventIdleSleep preventSuspendOnSleep
)}
Looking through other questions I found out that the crash message indicates that I didn't end a task properly, so when its time expired the OS ended it and crashed my app.
So I added some NSLogs:
- (void)applicationDidEnterBackground:(UIApplication *)application
{
[self saveContext];
[Settings setCallLock:YES];
[self saveStuff];
if ([self isBackgroundTaskNeeded])
{
UIApplication* app = [UIApplication sharedApplication];
bgTask = [app beginBackgroundTaskWithExpirationHandler:^{
[self pauseDownloads];
NSLog(@"Debug - Ending background task %d",bgTask);
[app endBackgroundTask:bgTask];
NSLog(@"Debug - Background task %d ended",bgTask);
bgTask = UIBackgroundTaskInvalid;
}];
NSLog(@"Debug - Starting background task %d",bgTask);
[self initBackground];
}
}
and found out that the task was called twice when it crashed:
Nov 7 12:30:02 iPad MyApp[3096] <Warning>: Debug - Starting background task 7
Nov 7 12:30:30 iPad MyApp[3096] <Warning>: Debug - Starting background task 8
Nov 7 12:33:26 iPad MyApp[3096] <Warning>: Debug - Ending background task 8
Nov 7 12:33:26 iPad MyApp[3096] <Warning>: Debug - Background task 8 ended
Nov 7 12:33:26 iPad MyApp[3096] <Warning>: Debug - Ending background task 0
Nov 7 12:33:26 iPad MyApp[3096] <Warning>: Debug - Background task 0 ended
I wasn't able to tell when the double call happens and why. So question is why is the task being called twice and is there a way to avoid it?
Edit:
- (void) pauseDownloads
{
for (AFDownloadRequestOperation *operation in self.operationQueue.operations)
{
if(![operation isPaused])
{
[operation pause];
}
}
}
