public static void Clear() { if (_instance != null) { lock (_instanceLock) { if (_instance != null) { _instance = null; } } } }
public Front() { NavigationPage.SetHasBackButton(this, false); //NavigationPage.SetHasNavigationBar(this, false); InitializeComponent(); this.Title = "Welcome " + CrossSecureStorage.Current.GetValue("username").ToUpper(); BarBackgroundColor = Color.FromHex("#484559"); BarTextColor = Color.White; Popup = new PopupMenu() { BindingContext = ViewModel }; var doneItem = new ToolbarItem { Icon = "logout.png" }; var infoItem = new ToolbarItem { Icon = "info.png" }; this.ToolbarItems.Add(infoItem); this.ToolbarItems.Add(doneItem); doneItem.Clicked += async(object sender, System.EventArgs e) => { var answer = await DisplayAlert("Logout", "Do you want to logout? ", "Yes", "No"); if (answer) { ApiClientWinAuthExampleSingleton.Clear(); CrossSecureStorage.Current.DeleteKey("username"); CrossSecureStorage.Current.DeleteKey("password"); CrossSecureStorage.Current.DeleteKey("token"); Application.Current.MainPage = new NavigationPage(new Login()); await Navigation.PopToRootAsync(true); } }; infoItem.Clicked += async(object sender, System.EventArgs e) => { await DisplayAlert("About", "Official MIAO App, created by NIKO", "Thanks"); }; barcode = new TestScan(); overview = new MainPage(); findInstrument = new FindInstrument(); this.CurrentPageChanged += (object sender, EventArgs e) => { var i = this.Children.IndexOf(this.CurrentPage); if (i == 1) { MessagingCenter.Send <Front>(this, "itemPage"); } }; Children.Add(barcode); Children.Add(overview); Children.Add(findInstrument); var pages = Children.GetEnumerator(); // pages.MoveNext(); // First page // pages.MoveNext(); // Second page //CurrentPage = null; }