Setting Local Notifications on a new thread?

Question

I need to know if it is possible to create a new thread to handle setting local notifications.

My app depends heavily on these notifications, so I want to make the app work while the phone sets the notifications.

Example:

(now)

you launch the app, the app hangs at the splash screen to set the local notifications, then it launches.

(I want)

The app launches and is usable while the Local notifications are set.

I need some sample code, too, please :)

(for the record, i am setting 60 local notifications each time the app enters foreground for my own reasons...)

Thanks!!

score 3 · Answer 1 · answered Nov 30 '10 at 18:12

3

One way to do threads is with is with performSelectorInBackground.

For example:

[myObj performSelectorInBackground:@selector(doSomething) withObject:nil];

You should note, however, that Apple is pretty strongly recommending that you use higher-level concepts like NSOperations and Dispatch Queues instead of explicitly spawning threads. See the Concurrency Programming Guide

answered Nov 30 '10 at 18:12

David Gelhar

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Thanks for your contribution! – Mazyod Nov 30 '10 at 18:30
it's crashing even more. :( – Baby Groot Oct 23 '13 at 06:26

score 3 · Accepted Answer · edited May 24 '12 at 07:56

Yes this can be done, I do it all the time:

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
    // Add the navigation controller's view to the window and display.
    [NSThread detachNewThreadSelector:@selector(scheduleLocalNotifications) toTarget:self withObject:nil];
    [window addSubview:navigationController.view];
    [window makeKeyAndVisible];

    return YES;
}

-(void) scheduleLocalNotifications
{

    NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];

    for (int i = 0; i < 60; i++)
    {
        UILocalNotification *localNotif = [[UILocalNotification alloc] init];
        if (localNotif == nil)
            return;
        NSDate *sleepDate = [[NSDate date] dateByAddingTimeInterval:i * 60];
        NSLog(@"Sleepdate is: %@", sleepDate);

        localNotif.fireDate = sleepDate;    

        NSLog(@"fireDate is %@",localNotif.fireDate);
        localNotif.timeZone = [NSTimeZone defaultTimeZone];
        localNotif.alertBody = [NSString stringWithFormat:NSLocalizedString(@"This is local notification %i"), i];

        localNotif.alertAction = NSLocalizedString(@"View Details", nil);
        localNotif.soundName = UILocalNotificationDefaultSoundName;
        localNotif.applicationIconBadgeNumber = 1;

        [[UIApplication sharedApplication] scheduleLocalNotification:localNotif];
        NSLog(@"scheduledLocalNotifications are %@", [[UIApplication sharedApplication] scheduledLocalNotifications]);
        [localNotif release];

    }

    [pool release];
}

Taken from a project I am working on now, I can confirm that It works as expected.

EDIT:
Example was leaking in scheduleLocalNotifications because handling the NSAutoreleasePool was missing – now it's added to the example.

Using UIApplication out of the main thread is not safe and can cause 'Unexpected Results'. I'd question why you need to do it off thread. I doubt it's taking up much time. If it needs to be off thread, you still need to run 'scheduleLocalNotification' on the main thread to be safe. — Brian King, Dec 23 '10 at 18:18

Setting Local Notifications on a new thread?

2 Answers2