Beacons.Universal.Background.MainPage.MainPage C# (CSharp) Метод

        public MainPage()
        {
            this.InitializeComponent();
            
            beacons = new ObservableCollection<iBeaconData>();
            this.DataContext = beacons;

            //Unregister the old task
            var taskAdvertisementWatcher = BackgroundTaskRegistration.AllTasks.Values.Where(t => t.Name == taskName).FirstOrDefault();
            if (taskAdvertisementWatcher != null)
            {
                taskAdvertisementWatcher.Unregister(true);
                taskAdvertisementWatcher = null;
                Button_Click(null, null);
            }
        }
        protected override void OnNavigatedTo(NavigationEventArgs e)