controllerObserveDelegate.swift

    override func viewDidLoad() {
        
        super.viewDidLoad()

        NotificationCenter.default.addObserver(self,
                                               selector: #selector(applicationDidEnterBackground),
                                               name: NSNotification.Name.UIApplicationDidEnterBackground,
                                               object: nil)
        
        NotificationCenter.default.addObserver(self,
                                               selector: #selector(applicationDidEnterForeground),
                                               name: NSNotification.Name.UIApplicationWillEnterForeground,
                                               object: nil)
        
    }
    deinit {
        NotificationCenter.default.removeObserver(self)
        NotificationCenter.default.removeObserver(self)
    }

    func applicationDidEnterBackground() {
        log(text: "App backgrounded", pauseLog: false)
    }
    
    func applicationDidEnterForeground() {
        log(text: "App foregrounded", pauseLog: false)
    }