Detect If push notifications were received when app is not launched and user didn't open the app through them

Question

Is it possible to detect if a push notification was received while the app was offline (not in background or foreground ? given the case that the user open the app directly from the spring board and not from the push notification alert.

Answer 1

From documentation of - application:didReceiveRemoteNotification:fetchCompletionHandler:

the system calls this method when your app is running in the foreground or background.

But, as you may have found out by your question

However, the system does not automatically launch your app if the user has force-quit it. In that situation, the user must relaunch your app or restart the device before the system attempts to launch your app automatically again.

Answer 2

In your AppDelegate do this (sorry for swift implementation):

func application(application: UIApplication, didFinishLaunchingWithOptions launchOptions: [NSObject: AnyObject]?) -> Bool {

    // We see if we have a recent push notification date stored in the user defaults.
    // If there hasn't been a recent one sent this if block will not be entered.
    if let mostRecentPushNotificationDate = NSUserDefaults.standardUserDefaults().objectForKey("mostRecentPushNotification") as? NSDate {

        // We find the difference between when the notification was sent and when the app was opened
        let interval = NSDate().timeIntervalSinceDate(mostRecentPushNotificationDate)

        // Check to see if we opened from the push notification
        if let notification = launchOptions?[UIApplicationLaunchOptionsRemoteNotificationKey] as? [String: AnyObject] {
            print("we opened from the push notifcation and the time difference was \(interval) seconds.")
        }

        // We did not open from a push notification
        else {
            print("we opened from the spring board and the time difference was \(interval) seconds.")
        }

        // We remove the object from the store so if they open the app without a notification being sent we don't check this if block
        NSUserDefaults.standardUserDefaults().removeObjectForKey("mostRecentPushNotification")
    }


    return true
}

func application(application: UIApplication, didReceiveRemoteNotification userInfo: [NSObject : AnyObject], fetchCompletionHandler completionHandler: (UIBackgroundFetchResult) -> Void) {

    // Set a flag when a push notification was sent
    NSUserDefaults.standardUserDefaults().setObject(NSDate(), forKey: "mostRecentPushNotification")
}