不显示AppDelegate中的第一个ViewController

Question

我有一个涂成红色的UIViewController，我想在第一个屏幕上看到这个viewController，但是从不以ViewController开头，我在做什么错？

UIWindow window;
        [Export("window")]
        public UIWindow Window { get; set; }

        [Export("application:didFinishLaunchingWithOptions:")]
        public bool FinishedLaunching(UIApplication application, NSDictionary launchOptions)
        {
            window = new UIWindow(UIScreen.MainScreen.Bounds);
            LoginView loginView = new LoginView();
            UINavigationController navigation = new UINavigationController(loginView);


            window.MakeKeyAndVisible();
            window.RootViewController = navigation;
            return true;
        }

这是我的ViewController，怎么了？

public partial class LoginView : UIViewController

    {
        public override void ViewDidLoad()
        {
            base.ViewDidLoad();
            View.BackgroundColor = UIColor.Red;
        }

我遇到此错误： 2019-11-05 15：15：27.806644-0400 ETracker [4195：115403] SecTaskLoadEntitlements失败error = 22 cs_flags = 200，pid = 41952019-11-05 15：15：27.807241-0400 ETracker [4195：115403] SecTaskCopyDebug描述：ETracker [4195] / 0＃-1 LF = 02019-11-05 15：15：27.825039-0400 ETracker [4195：115403] SecTaskLoadEntitlements失败error = 22 cs_flags = 200，pid = 41952019-11-05 15：15：27.825367-0400 ETracker [4195：115403] SecTaskCopyDebug描述：ETracker [4195] / 0＃-1 LF = 0

Answer 1

在iOS 13（及更高版本）上，场景委托接管了应用程序委托。最重要的是，窗口的概念是取而代之的是场景。一个应用可以包含多个场景，并且现在，一个场景用作应用程序的用户界面的背景，并且内容。

从iOS 13开始，SceneDelegate负责设置应用程序的场景以及设置其初始视图。

[Export ("scene:willConnectToSession:options:")]
public void WillConnect (UIScene scene, UISceneSession session, UISceneConnectionOptions connectionOptions)
{
    // Use this method to optionally configure and attach the UIWindow `window` to the provided UIWindowScene `scene`.
    // If using a storyboard, the `window` property will automatically be initialized and attached to the scene.
    // This delegate does not imply the connecting scene or session are new (see UIApplicationDelegate `GetConfiguration` instead).

    UIWindowScene myScene = scene as UIWindowScene;
    Window = new UIWindow(myScene);
    UIViewController loginView = new UIViewController();
    UINavigationController navigation = new UINavigationController(loginView);
    Window.RootViewController = navigation;
    Window.MakeKeyAndVisible();

}

有关更多信息，您可以阅读this article和watch the official video of Optimizing App Launch in iOS13