iBeacon-App: Custom code when launched from lockscreen - ios

Question

Since iOS 8, the operating system is indicating an iBeacon-enabled application, which is inside a defined region, with an icon in the left bottom corner of the lockscreen (see http://appleinsider.com/articles/14/06/03/apples-ios-8-uses-ibeacon-tech-brings-location-aware-app-access-to-lock-screen for reference).
I want to make use of this feature in my app by running custom code if the app is launched from the lockscreen (e.g. switch to specific view).
How to check in the Application Delegate if the app was launched from the lockscreen? I couldn't find any documentation on this.

Answer 1

AFAIK, it's not possible to detect whether your app was brought into the foreground via the "Suggested apps" feature (that's what Apple calls the icon on the lock screen), or by any other means (app switcher, app icon on the home screen).
You could do some heuristics. If the app came into the foreground and there are no beacons in range (you can check that with ranging), then there's no way it was via the lock screen icon.

Answer 2

There is a Excellent article on this topic by Matt Coneybeare
Below I have pointed out some of the important points from that article , for more info check out that article.
From Article of Matt Coneybeare
On iOS 6 and lower it could be detected using the current UIApplicationState in applicationWillEnterForeground
UIApplicationState state = [[UIApplication sharedApplication] ApplicationState];
if (UIApplicationStateInactive == state)
// Coming from locked screen (iOS 6)
else
// Coming from Springboard, another App, etc...
But From iOS 7 onwards, the state value is UIApplicationStateBackground in both scenarios.
It seems that there is no possible way to detect where the App is being launched from on iOS 7, but there is a way to detect if you are going to the Lockscreen vs Homescreen (or something else).
The trick is to read the screen brightness in applicationDidEnterBackground.
When the App hits the background due to the lock button being pressed or an auto-lock timeout, the brightness will be 0.0 on iOS 7.
Otherwise, it will be > 0 when the home button is pressed or another App launched from the multitask selector or notification center.

Answer 3

When the app is launched by beacon detection, your AppDelegate's (void)locationManager:(CLLocationManager *)manager didEnterRegion:(CLRegion *)region method will be invoked.
You can put any custom code inside that method, perhaps to set a flag indicating this is how the app was launched.

Answer 4

The following code shows how to detect that tapping a local notification launched the app from the lock screen. For details, see: https://developer.apple.com/library/mac/documentation/NetworkingInternet/Conceptual/RemoteNotificationsPG/Chapters/IPhoneOSClientImp.html
- (BOOL)application:(UIApplication *)app didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
UILocalNotification *localNotif =
[launchOptions objectForKey:UIApplicationLaunchOptionsLocalNotificationKey];
if (localNotif) {
// do something
}
...
return YES;
}
This is not the same as launching the app by tapping the icon on the bottom of the lock screen, but it is similar. If you present a local notification on beacon detection it will work as described above if tapped.
I believe the app icon shows up on the bottom of the lock screen only if your app is launched into the background by beacon detection and does not present a local notification. If this is the case you are looking for, you might examine the launchOptions above and see if a different key is present in this case.