How to clear just the notification in iOS - ios

Question

If the user has alert style set to Banners. They can receive more than 1 notification without them being prompted to clear it. They then go to use their phone, and they have say 3 stored. If the click on the latest one & it opens the App, I want to only clear just this one notification, I also need to go badgeCount--;
How can I achieve it with the code below? (At the moment it's set to clearing all which I don't want...) I've also noticed that sometimes it DOES update the badge number. But if I toggle back to the iOS Home screen, and pull down the notifications menu, it's still there!
- (void)application:(UIApplication *)application didReceiveRemoteNotification:(NSDictionary *)userInfo
{
if([[userInfo valueForKey:#"aps"] valueForKey:#"alert"] != nil) {
NSString *message = [[userInfo valueForKey:#"aps"] valueForKey:#"alert"];
if(message != nil) {
UIAlertView *alertView = [[UIAlertView alloc] initWithTitle:#"Usage Alert"
message:message delegate:self cancelButtonTitle:#"Cancel" otherButtonTitles:#"Ok", nil];
[alertView show];
[[UIApplication sharedApplication] setApplicationIconBadgeNumber: 0];
[[UIApplication sharedApplication] cancelAllLocalNotifications];
}
}
}

Answer 1

-(void)application:(UIApplication *)application didReceiveLocalNotification:(UILocalNotification *)notification
{
UIApplication *app = [UIApplication sharedApplication];
NSInteger badgeNumber = [app applicationIconBadgeNumber];// Take the current badge number
badgeNumber--; // decrement by one
[app setApplicationIconBadgeNumber:badgeNumber]; // set ne badge number
[app cancelLocalNotification:notification]; // cancel the received notification. It will clear the notification from banner alos
}

Answer 2

You can add
- (void)application:(UIApplication *)application didReceiveLocalNotification:(UILocalNotification *)notification
to your app delegate. This will be called and there you can use
[[UIApplication sharedApplication] cancelLocalNotification:notification];
to remove the specific notification and decrement the badge count.

Answer 3

I want to warn against calling
[[UIApplication sharedApplication] setApplicationIconBadgeNumber:bg_NUM]
from
- (void)application:(UIApplication *)application didReceiveLocalNotification:(UILocalNotification *)notification
method!
If your scheduled local notification with some badge number, then badge will be set asynchronously some milliseconds after enter to -didReceiveLocalNotification
for sample:
-(void)application:(UIApplication *)application didReceiveLocalNotification:(UILocalNotification *)notification {
[[UIApplication sharedApplication] setApplicationIconBadgeNumber:0];
// ^^^ maybe not reset badge to 0!! ^^^
}
another code:
-(void)application:(UIApplication *)application didReceiveLocalNotification:(UILocalNotification *)notification {
sleep(1); //waiting for system is set our scheduled badge
[[UIApplication sharedApplication] setApplicationIconBadgeNumber:0];
// ^^^ most chances for reset badge to 0 ^^^
}
Testing code, screen touches schedule local notifications
and calculate delay before system real set badge:
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
[[UIApplication sharedApplication] setApplicationIconBadgeNumber:0];
UILocalNotification *localNotif = [[[UILocalNotification alloc] init] autorelease];
localNotif.applicationIconBadgeNumber = rand()%100+1;
localNotif.fireDate = [NSDate dateWithTimeIntervalSinceNow:1];
[[UIApplication sharedApplication] scheduleLocalNotification:localNotif];
}
[...]
- (void)application:(UIApplication *)application didReceiveLocalNotification:(UILocalNotification *)notification {
CFAbsoluteTime startTime = CFAbsoluteTimeGetCurrent();
while ([UIApplication sharedApplication].applicationIconBadgeNumber == 0) sleep(0);
NSLog(#"badge set: %d after %f sec.", [UIApplication sharedApplication].applicationIconBadgeNumber, CFAbsoluteTimeGetCurrent()-startTime);
}
output:
badge set: 41 after 0.000839 sec.
badge set: 9 after 0.000754 sec.
badge set: 56 after 0.076026 sec.
badge set: 17 after 0.069889 sec.
badge set: 8 after 0.056245 sec.
badge set: 71 after 0.120729 sec.
badge set: 28 after 0.122720 sec.
badge set: 17 after 0.000758 sec.
this testing in iOS 4.2/4.3/5.0/6.1 on different devices
Be careful when you reset badge number in -didReceiveLocalNotification message!
(this true only for LocalNotification /not remote push/ and only if application is active on
receive moment)