Direct Integration - How to receive message when "Safari View Controller" is closed without successful payment

[Quentie]

Thanks for your nice sample.
I'm currently a bit confused on how I can get a notification if someone hits the "Done" button in the "Safari View Controller" without actually finishing the payment process? I currently only get a message if it worked, but no clue how to find out if not :(

Could you give me a hint?

// Direct integration
let url = URL(string: "...")
let request:URLRequest = URLRequest(url : url!);
paypalCheckout.handleIfPPCheckout(request);

// Confusion I only get notified when checkout worked. How do I get notified, when it did not work or someone hit the Done button?
func application(_ application: UIApplication, open url: URL, sourceApplication: String?, annotation: Any) -> Bool {

    let instance:PYPLCheckout = PYPLCheckout.sharedInstance() as! PYPLCheckout;
    let wasHandled:Bool = instance.openURL(application, open: url as URL, sourceApplication: sourceApplication as String!, annotation: annotation);

    if (wasHandled) {
        print("worked")
    }

    return wasHandled
}