How to schedule multiple local notifications without freezing UI? - iphone

Question

In my PhoneGap 1.3 offline app I'm using modified iOS local notification plugin found in official plugin GitHub page.
I need to schedule a repeating notification (weekly/monthly), or multiple single notifications fired on every 2 weeks, based on user defined setting.
The problem occurs when I'm trying to schedule those 26 notifications to be fired on every 2 weeks.
Currently I'm using this to achieve that:
for (int i = 1; i < 26; i++)
{
UILocalNotification *localNotif = [[UILocalNotification alloc] init];
if (localNotif == nil) {
return;
}
NSDate *date = [[NSDate date] dateByAddingTimeInterval: i * 60 * 60 * 24 * 7 * 2];
localNotif.fireDate = date;
localNotif.timeZone = [NSTimeZone defaultTimeZone];
localNotif.alertBody = [NSString stringWithFormat:#"%i: %#", i, msg];
localNotif.hasAction = NO;
localNotif.soundName = UILocalNotificationDefaultSoundName;
localNotif.applicationIconBadgeNumber = 0;
[[UIApplication sharedApplication] scheduleLocalNotification:localNotif];
[localNotif release];
}
When running this on iPhone 3G or iPod Touch 2 the UI freezes for about 3 - 5 seconds which is a big no no. Is there a way to optimize scheduling notifications?
I know that using only weekly and monthly repeating notifications would solve the problem but the client wants every 2 weeks, every 2 months, and every 3 months notifications, so I need to schedule multiple notifications.
I have tried to run the loop in new thread using [NSThread detachNewThreadSelector:...] which raises new problems (crashes every now and then).
Are iPhones released after 3G that much faster that delay/froze won't exist? I only have those 2 ancient devices to test with.

Answer 1

I would suggest either performing the creation in a background thread using this: (void)performSelectorInBackground:(SEL)aSelector withObject:(id)arg
Or I would try to rethink the process. Perhaps instead of creating a years worth of 2 week reminders at once just create a couple and set something else up to create the rest. Or maybe even just create one and store a repeating bool with it so when it fires it also creates the next one.