Keep NSTimer running when app is in background (multitasking)

me0007 · September 2010

I hope there's an expert out there who can help me with this:

I googled up and down, but could not find any information if there is any way to keep a running NSTimer active when the app is running in the background (iOS 4)?

Thanks for any help!

Steve

KernelPanic · September 2010

me0007;242901 said:
I hope there's an expert out there who can help me with this:

I googled up and down, but could not find any information if there is any way to keep a running NSTimer active when the app is running in the background (iOS 4)?

Thanks for any help!

Steve

I am having same problem and I've managed to setup UILocalNotification and it works fine. But, I get event fired once timer gets to zero (i.e., when current clock is equal to setup) instead of getting event, for instance, every second. Here is sample code:

- (void)btnSetupNotificationClicked:(id)sender
{
	UILocalNotification* pOrderCompletedNotification=[[UILocalNotification alloc] init];
	if(pOrderCompletedNotification!=nil)
	{
		[pOrderCompletedNotification setFireDate:[[NSDate alloc] initWithTimeIntervalSinceNow:5.00]];
//		[pOrderCompletedNotification setApplicationIconBadgeNumber:1];
		[pOrderCompletedNotification setTimeZone:[NSTimeZone systemTimeZone]];
		[pOrderCompletedNotification setSoundName:@\"OrderCompleted.m4a\"];
		[pOrderCompletedNotification setAlertBody:@\"Order Completed\"];
		[pOrderCompletedNotification setAlertAction:nil];
		[pOrderCompletedNotification setHasAction:NO];
	
		UIApplication* pApplication=[UIApplication sharedApplication];
		if(pApplication!=nil)
		{
			[pApplication scheduleLocalNotification:pOrderCompletedNotification];
		}
		else
		{
			NSLog(@\"Application singleton allocation error.\");
		}

		[pOrderCompletedNotification release];
		[pApplication release];
	}
	else
	{
		NSLog(@\"Local notification creation error.\");
	}	// if
}

me0007 · September 2010

Thanks for that. I'll give it a try.

Anyway: does that mean that there's no direct way to keep an NSTimer running when in background?

KernelPanic · September 2010

me0007;242986 said:
Thanks for that. I'll give it a try.

Anyway: does that mean that there's no direct way to keep an NSTimer running when in background?

As my newbie knowledge knows, I (for now) think there is no way.

zero_ · September 2010

maybe you can use some code of
this tutorial

me0007 · September 2010

zero_;243322 said:
maybe you can use some code of
this tutorial

Thanks, but the problem is not sleeping or deep sleeping. The problem is that an NSTimer stops ticking once an app is in background mode.

zero_ · September 2010

yes i've understand, but if you play a "nosound" during the background you can keepup the timer:d

me0007 · September 2010

zero_;243337 said:
yes i've understand, but if you play a "nosound" during the background you can keepup the timer:d

Ah, OK... now I understand. Worth to have a look at it, but as far as I can tell this might be a problem when you want to get the app authorized by Apple...

zero_ · September 2010

me0007;243445 said:
Ah, OK... now I understand. Worth to have a look at it, but as far as I can tell this might be a problem when you want to get the app authorized by Apple...

i've not find this authorization limit by Apple:D

me0007 · September 2010

zero_;243482 said:
i've not find this authorization limit by Apple:D

OK, I tried that, but it actually does not do what I was looking for. The silent sound is played properly every x seconds (I checked that by replacing it with an audible sound). But: once the app is set to background mode, the app starts to sleep and all running NSTimers, too. When I re-activate the app, I hear that all 'silent sounds' that should have been played while the app was in background mode, are played right one after the other. Also all other NSTimers continue to tick.

So, this does not help. It does not keep other timers ticking when in background. Too bad... :(

KernelPanic · September 2010

me0007;243532 said:
OK, I tried that, but it actually does not do what I was looking for. The silent sound is played properly every x seconds (I checked that by replacing it with an audible sound). But: once the app is set to background mode, the app starts to sleep and all running NSTimers, too. When I re-activate the app, I hear that all 'silent sounds' that should have been played while the app was in background mode, are played right one after the other. Also all other NSTimers continue to tick.

So, this does not help. It does not keep other timers ticking when in background. Too bad... :(

I also do not have significant progress ... Sorry.

Howdy, Stranger!

Forums

Keep NSTimer running when app is in background (multitasking)

Replies