Xamarin.Auth正在重新初始化应用程序

我只在UWP上遇到这个问题

 private void Button_OnClicked(object sender, EventArgs e)
        {
            var clientId = Constants.GoogleUWPClientID;
            var clientSecret = Constants.GoogleUWPClientSecret;
            var redirectUrl = Constants.GoogleUWPRedirectUrl;

            var auth =  new OAuth2Authenticator(
                clientId: clientId,
                clientSecret: clientSecret,
                scope: Constants.GoogleScope,
                authorizeUrl: new Uri(Constants.GoogleAuthorizeUrl),
                accessTokenUrl: new Uri(Constants.GoogleAccessTokenUrl),
                redirectUrl: new Uri(redirectUrl),
                getUsernameAsync: null,
                isUsingNativeUI: true
            );

            // Login Events
            auth.Completed += AuthOnCompleted;
            auth.Error += AuthOnError;
            auth.IsLoadableRedirectUri = true;


            AuthenticationState.Authenticator = auth;

            var presenter = new Xamarin.Auth.Presenters.OAuthLoginPresenter();
            presenter.Login(auth);
        }

我确实在UWP上初始化了Xamarin.Auth

Xamarin.Forms.Forms.Init(e);
global::Xamarin.Auth.Presenters.UWP.AuthenticationConfiguration.Init();

这是CompletedEvent处理程序

private async void AuthOnCompleted(object sender, AuthenticatorCompletedEventArgs authenticatorCompletedEventArgs)
        {
            //var auth = sender as Xamarin.Auth.OAuth2Authenticator;
            //auth.DoNotEscapeScope = true;

            // We presented the UI, so it's up to us to dimiss it on iOS.
            //DismissViewController(true, null);

            if (authenticatorCompletedEventArgs.IsAuthenticated)
            {
                var request = new OAuth2Request("GET", new Uri(Constants.GoogleUserInfoUrl), null, authenticatorCompletedEventArgs.Account);
                var response = await request.GetResponseAsync();

                if (response != null)
                {
                    var userJson = response.GetResponseText();
                    var user = JsonConvert.DeserializeObject<GoogleUser>(userJson);

                    //UserPicture = user.Picture;
                    //GivenName = user.GivenName;
                    //Email = user.Email;
                }
            }
            else
            {
                // The user cancelled
                //ErrorMessage = "Cancelled authentication !";
            }

        }

---

我已经测试了您的代码并复制了“问题”。验证完成后，应用程序将刷新是正常行为。因为当显示登录页面时，将替换当前内容页面

public void Login(Authenticator authenticator)
{
    authenticator.Completed += AuthenticatorCompleted;

    System.Type page_type = authenticator.GetUI();

    Windows.UI.Xaml.Controls.Frame root_frame = null;
    root_frame = Windows.UI.Xaml.Window.Current.Content as Windows.UI.Xaml.Controls.Frame;
    root_frame.Navigate(page_type, authenticator);

    return;
}

当

AuthOnCompleted

时，便携库将被重新加载

public MainPage()
{
    this.InitializeComponent();

    LoadApplication(new XamarinAuthTest.App());
}

因此，应用程序将“重新启动/刷新”

编辑01

---

如果

NavigationCacheMode=“Enabled”

，则在完成身份验证后，应用程序将不会重新启动。因为

MainPage

的构造函数方法不会在缓存模式下执行。如果应用程序可以接受页面缓存设计模式。你不必担心应用程序的性能。

我已经测试了你的代码并重现了“问题”。验证完成后，应用程序将刷新是正常行为。因为当显示登录页面时，将替换当前内容页面

public void Login(Authenticator authenticator)
{
    authenticator.Completed += AuthenticatorCompleted;

    System.Type page_type = authenticator.GetUI();

    Windows.UI.Xaml.Controls.Frame root_frame = null;
    root_frame = Windows.UI.Xaml.Window.Current.Content as Windows.UI.Xaml.Controls.Frame;
    root_frame.Navigate(page_type, authenticator);

    return;
}

当

AuthOnCompleted

时，便携库将被重新加载

public MainPage()
{
    this.InitializeComponent();

    LoadApplication(new XamarinAuthTest.App());
}

因此，应用程序将“重新启动/刷新”

编辑01

如果

NavigationCacheMode=“Enabled”

，则在完成身份验证后，应用程序将不会重新启动。因为

MainPage

的构造函数方法不会在缓存模式下执行。如果应用程序可以接受页面缓存设计模式。你不必担心应用程序的性能