Question

I have the following code in ViewController.m:

-(void) checker {
    UILocalNotification *notification = [[UILocalNotification alloc] init];
    [notification setAlertBody: @"Im your local notification"];
    [notification setFireDate: [NSDate dateWithTimeIntervalSinceNow: 1]];
    [notification setTimeZone: [NSTimeZone defaultTimeZone]];
    [UIApplication setScheduledLocalNotifications: [NSArray arrayWithObject: notification]];
}

The last line produces a warning:

Class method ‘+setScheduledLocalNotifications’ not found (return type defaults to id)

and it gives error while processing. How can I instantiate the notification? As I said I am new, if you can provide a complete answer it will be greatly appreciated.

Edit: I have a timer that repeats itself every 60 seconds and calls a function that puts a notification.

timer = [NSTimer scheduledTimerWithTimeInterval:60 target:self selector:@selector(checker) userInfo:nil repeats:YES];

/* ... */
-(void)checker {
    NSLog(@"Notification routine");
    UIApplication* app = [UIApplication sharedApplication];
    NSArray *oldNotifications = [app scheduledLocalNotifications];

    // Clear out the old notification before scheduling a new one.(if needed)
    if ([oldNotifications count] > 0)
        [app cancelAllLocalNotifications];

    // Create a new notification.
    UILocalNotification* alarm = [[[UILocalNotification alloc] init] autorelease];
    if (alarm) {
        alarm.fireDate = [NSDate dateWithTimeIntervalSinceNow:10];
        alarm.timeZone = [NSTimeZone defaultTimeZone];
        alarm.repeatInterval = 0;
        alarm.alertBody = @"Msg to show";
        [app scheduleLocalNotification:alarm];
    }
}

I can see the log only firing once a minute, but the oldNotifications count does not increase.

Answer 1

This is how I do it,

UIApplication* app = [UIApplication sharedApplication];
NSArray *oldNotifications = [app scheduledLocalNotifications];

// Clear out the old notification before scheduling a new one.(if needed)
if ([oldNotifications count] > 0)
    [app cancelAllLocalNotifications];

// Create a new notification.
UILocalNotification* alarm = [[[UILocalNotification alloc] init] autorelease];
if (alarm)
{
    alarm.fireDate = [NSDate dateWithTimeIntervalSinceNow:60*60];//afterone hour
    alarm.timeZone = [NSTimeZone defaultTimeZone];
    alarm.repeatInterval = 0;
    alarm.soundName = @"alarmsound.caf";
    alarm.alertBody = @"Msg to show";
    [app scheduleLocalNotification:alarm];
}

update:

- (void)scheduleAlarmForDate:(NSDate*)theDate andBody:(NSString*)Body
{
    UIApplication* app = [UIApplication sharedApplication];
    NSArray *oldNotifications = [app scheduledLocalNotifications];

    // Clear out the old notification before scheduling a new one.
    if ([oldNotifications count] > 0)
        [app cancelAllLocalNotifications];

    // Create a new notification.
    UILocalNotification* alarm = [[UILocalNotification alloc] init];//Using ARC no autorelease
    if (alarm)
    {
        alarm.fireDate = theDate;
        alarm.timeZone = [NSTimeZone defaultTimeZone];
        alarm.repeatInterval = 0;
        alarm.soundName = @"alarmsound.caf";
        alarm.alertBody = Body;
        [app scheduleLocalNotification:alarm];
    }
}

now if I call this method twice,

 NSDate *fireDate1 = [NSDate dateWithTimeIntervalSinceNow:4.0];
[self scheduleAlarmForDate:fireDate1 andBody:@"My alertBody 1"];

NSDate *fireDate2 = [NSDate dateWithTimeIntervalSinceNow:6.0];
[self scheduleAlarmForDate:fireDate2 andBody:@"My alertBody 2"];

the first alarm will be canceled,,