public static void ShowOAuthView(OAuth2WebServerFlow oAuth)
        {
            currentPage = Application.Current.MainPage;

            var oAuthView = new FlexibleWebAuthView();

            oAuth.InvokeUserAuthorization(oAuthView);
            Application.Current.MainPage = oAuthView;
            oAuthView.Navigate(oAuthView.AuthorizeUrl);

            oAuthView.OAuthSuccess += async(sender, args) =>
            {
                await oAuth.ProcessAuthorizationAsync(sender as Uri);

                await Application.Current.MainPage.DisplayAlert("Access Token", oAuth.AccessToken.Code, "OK", "Cancel");

                RestoreView();
                OnAuthenticated?.Invoke(oAuth, new AuthenticatedEventArgs(oAuth.AccessToken.Code, oAuth.AccessToken.RefreshToken, oAuth.AccessToken.Expires));
            };
        }
        public static void ShowOAuthView(OAuth2WebServerFlow oAuth)
        {
            StoreElements();
            var webAuthView = new FlexibleWebAuthView {
                Height = Window.Current.Bounds.Height
            };

            oAuth.InvokeUserAuthorization(webAuthView);
            var elements = GetUIElementCollectionInstance();

            elements.Clear();
            elements.Add(webAuthView);
            webAuthView.Navigate(webAuthView.AuthorizeUrl);
            webAuthView.OAuthSuccess += async(sender, args) =>
            {
                await oAuth.ProcessUserAuthorizationAsync(sender as Uri);

                RestoreView();
                OnAuthenticated?.Invoke(oAuth, new AuthenticatedEventArgs(oAuth.AccessToken.Code, oAuth.AccessToken.RefreshToken, oAuth.AccessToken.Expires));
                await new MessageDialog("Access Token Received: " + oAuth.AccessToken.Code).ShowAsync();
            };
        }