Question

I want to implement local notification in my clock app.Basically i want that a music file should be played after every half an hour like in ship’s clock in which chimes are played after every 30 minutes.

Can anyone give rough idea as how i can implement this functionality even when the app enters in background?

Answer 1

I recently used the Local notification stuff and used the following functions

//Setting up the Local Notifications

for (int i= 1 ; i<=10; i++) { //We here set 10 Notification after every 30 minutes from now you can modify it accordingly

    NSDate *scheduled = [[NSDate date] dateByAddingTimeInterval:60*30*i]; //These are seconds

    NSDictionary* dataDict = [NSDictionary dictionaryWithObjectsAndKeys:scheduled,FIRE_TIME_KEY,@"Background Notification received",NOTIFICATION_MESSAGE_KEY,nil];

    [self scheduleNotificationWithItem:dataDict];

}

Where scheduleNotificationWithItem is defined as

- (void)scheduleNotificationWithItem:(NSDictionary*)item  {

    UILocalNotification *localNotification = [[UILocalNotification alloc] init];

    if (localNotification == nil)   return;

    localNotification.fireDate =  [item valueForKey:FIRE_TIME_KEY];

    localNotification.timeZone = [NSTimeZone defaultTimeZone];

    localNotification.alertBody = [NSString stringWithFormat:NSLocalizedString(@"%@", nil), [item valueForKey:NOTIFICATION_MESSAGE_KEY]];

    localNotification.alertAction = NSLocalizedString(@"View Details", nil);

    localNotification.soundName = UILocalNotificationDefaultSoundName;

    localNotification.userInfo = item;

    [[UIApplication sharedApplication] scheduleLocalNotification:localNotification];

    [localNotification release];
}

Finally you can handle these notifications as

You can handle these notifications as follows

- (void)application:(UIApplication *)application didReceiveLocalNotification:(UILocalNotification *)notification {

// Do the required work you can obtain additional Info via notification.userInfo which happens to be a dictionary

}

reading the developer documentation will help you more to understand the stuff.Hope it helps