即使添加了SceneDelegate并更新了Info.plist之后，Xcode 11黑屏上的iOS13 [英] iOS13 on Xcode 11 Black screen even after adding SceneDelegate and updating Info.plist

问题描述

我目前正在使用Xcode 11，Target iOS 13.0(该应用程序在所有低于iOS 12.1至12.4的所有版本都可以正常工作)的情况下出现黑屏，我想让我的应用程序同时适用于12.1以上的iOS用户以及目前正在运行的13.0尽管将以下SceneDelegate添加到了我现有的项目中，并且

I am currently getting a blank screen with Xcode 11, Target iOS 13.0 (the app works fine with all below versions iOS 12.1 till 12.4), I want to make my App work for both iOS users above 12.1 and also 13.0 currently getting blank screen despite adding the below SceneDelegate to my existing project and

添加App Manifest文件

adding App Manifest file

import UIKit
    import SwiftUI

    @available(iOS 13.0, *)
    class SceneDelegate: UIResponder, UIWindowSceneDelegate {

        var window: UIWindow?

        func scene(_ scene: UIScene, willConnectTo session: UISceneSession, options connectionOptions: UIScene.ConnectionOptions) {

            //guard let _ = (scene as? UIWindowScene) else { return }

            let user  = UserDefaults.standard.object(forKey: "defaultsuserid")

            let userSelfIdent  = UserDefaults.standard.object(forKey: "userinitialident")

            if let windowScene = scene as? UIWindowScene {

                let internalWindow = UIWindow(windowScene: windowScene)

                if (user != nil && userSelfIdent != nil){
                     let mainstoryboard:UIStoryboard = UIStoryboard(name: "Main", bundle: nil)
                     let newViewcontroller:UIViewController = mainstoryboard.instantiateViewController(withIdentifier: "swrevealviewcontroller") as! SWRevealViewController
                        internalWindow.rootViewController = newViewcontroller
                        self.window = internalWindow
                        internalWindow.makeKeyAndVisible()
                }else {

                    guard let _ = (scene as? UIWindowScene) else { return }
                }
            }
        }

以下是我的AppDelegate，它将首先被调用并执行didFinishLaunchWithOptions方法.我想知道仅当我的Target ios小于13.0时才可以调用此方法，并在13.0之后调用SceneDelegate方法来初始化rootViewController吗?

The following is my AppDelegate which is getting called first and executing the didFinishLaunchWithOptions method. I want to know how can i make this method call only if my Target ios is less than 13.0 and call SceneDelegate method to initialize my rootViewController after 13.0?

@UIApplicationMain
class AppDelegate: UIResponder, UIApplicationDelegate {

    var window: UIWindow?


    @available(iOS 13.0, *)
    func application(_ application: UIApplication,
                     configurationForConnecting connectingSceneSession: UISceneSession,
                     options: UIScene.ConnectionOptions) -> UISceneConfiguration {
        return UISceneConfiguration(name: "Default Configuration", sessionRole: connectingSceneSession.role)
    }

    @available(iOS 13.0, *)
    func application(_ application: UIApplication, didDiscardSceneSessions sceneSessions: Set<UISceneSession>) {

    }



    @available(iOS 13.0, *)
    func scene(_ scene: UIScene, willConnectTo session: UISceneSession, options connectionOptions: UIScene.ConnectionOptions) {

        guard let _ = (scene as? UIWindowScene) else { return }

        if (user != nil && userSelfIdent != nil){

              let mainstoryboard:UIStoryboard = UIStoryboard(name: "Main", bundle: nil)
              let newViewcontroller:UIViewController = mainstoryboard.instantiateViewController(withIdentifier: "swrevealviewcontroller") as! SWRevealViewController
                self.window?.rootViewController = newViewcontroller
        }
    }

    func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplicationLaunchOptionsKey: Any]?) -> Bool {
        // Override point for customization after application launch.

        Thread.sleep(forTimeInterval: 3.0)

        UINavigationBar.appearance().barTintColor = UIColor(red:0.08, green:0.23, blue:0.62, alpha:1.0)

        if (user != nil && userSelfIdent != nil){

              let mainstoryboard:UIStoryboard = UIStoryboard(name: "Main", bundle: nil)
              let newViewcontroller:UIViewController = mainstoryboard.instantiateViewController(withIdentifier: "swrevealviewcontroller") as! SWRevealViewController
                self.window?.rootViewController = newViewcontroller
        }

        return true
    }

    func application(_ application: UIApplication, didRegisterForRemoteNotificationsWithDeviceToken deviceToken: Data) {

        let defaultUserID = UserDefaults.standard.string(forKey: "defaultUserID")


    }

    func application(_ application: UIApplication, didReceiveRemoteNotification userInfo: [AnyHashable : Any], fetchCompletionHandler completionHandler: @escaping (UIBackgroundFetchResult) -> Void) {

        switch (application.applicationState) {
        case UIApplicationState.active:
            do something

        case UIApplicationState.background, UIApplicationState.inactive:

            let mainstoryboard:UIStoryboard = UIStoryboard(name: "Main", bundle: nil)
            let newViewcontroller = mainstoryboard.instantiateViewController(withIdentifier: "swrevealviewcontroller") as! SWRevealViewController
            self.window?.rootViewController = newViewcontroller            
        }
    }

推荐答案

您在这里遇到了几个问题.阅读与应用程序生命周期相关的文档非常重要，该文档阐明了iOS 13下的内容以及iOS 12下的内容.

You have several issues here. It's important to read the documentation related to the app lifecycle which states what is called under iOS 13 and what is called under iOS 12.

您可能还想看一下我的支持iOS 12和13的单视图应用模板.

You may also want to see my Single View App template that supports iOS 12 and 13.

查看您的代码，这是问题的摘要:

Looking at your code, here is a summary of the problems:

AppDelegate:

AppDelegate:

• 仅在应用程序在iOS 12或更早版本下运行时，才应设置主窗口和根视图控制器.您需要在运行时进行检查.
• func scene(_ scene: UIScene, willConnectTo session: UISceneSession, options connectionOptions: UIScene.ConnectionOptions)方法不应位于应用程序委托中.
• 没有直接关系，但从不启动应用程序.删除Thread.sleep(forTimeInterval: 3.0)行.用户想要使用您的应用程序，而不是凝视启动屏幕的时间不会超过必要的时间.并且在应用启动时阻止主线程可能导致您的应用被杀死.

• You should only setup the main window and the root view controller if the app is being run under iOS 12 or earlier. You need to check this at runtime.
• The func scene(_ scene: UIScene, willConnectTo session: UISceneSession, options connectionOptions: UIScene.ConnectionOptions) method should not be in the app delegate.
• Not directly related but never sleep on app startup. Remove the Thread.sleep(forTimeInterval: 3.0) line. Users want to use your app, not stare at the launch screen longer than necessary. And blocking the main thread on app launch can cause your app to be killed.

SceneDelegate:

SceneDelegate:

• 这通常很好，但是没有必要使用guard let _ = (scene as? UIWindowScene) else { return }行，尤其是因为它位于已经进行了检查的if let内部.
• 您似乎没有使用SwiftUI，因此请删除该导入.

• This is mostly fine but there is no reason for the guard let _ = (scene as? UIWindowScene) else { return } line, especially since it is inside an if let that already does that check.
• You don't appear to be using SwiftUI so remove that import.

我将更新您的应用程序委托，使其更像这样:

I would update your app delegate to be more like this:

@UIApplicationMain
class AppDelegate: UIResponder, UIApplicationDelegate {
    var window: UIWindow?

    func application(_ application: UIApplication, willFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]? = nil) -> Bool {
        UINavigationBar.appearance().barTintColor = UIColor(red:0.08, green:0.23, blue:0.62, alpha:1.0)

        if #available(iOS 13.0, *) {
            // In iOS 13 setup is done in SceneDelegate
        } else {
            let window = UIWindow(frame: UIScreen.main.bounds)
            self.window = window

            if (user != nil && userSelfIdent != nil){
                let mainstoryboard:UIStoryboard = UIStoryboard(name: "Main", bundle: nil)
                let newViewcontroller:UIViewController = mainstoryboard.instantiateViewController(withIdentifier: "swrevealviewcontroller") as! SWRevealViewController
                window.rootViewController = newViewcontroller
            }
        }

        return true
    }

    func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {
        if #available(iOS 13.0, *) {
            // In iOS 13 setup is done in SceneDelegate
        } else {
            self.window?.makeKeyAndVisible()
        }

        return true
    }

    func applicationWillResignActive(_ application: UIApplication) {
        // Not called under iOS 13 - See SceneDelegate sceneWillResignActive
    }

    func applicationDidEnterBackground(_ application: UIApplication) {
        // Not called under iOS 13 - See SceneDelegate sceneDidEnterBackground
    }

    func applicationWillEnterForeground(_ application: UIApplication) {
        // Not called under iOS 13 - See SceneDelegate sceneWillEnterForeground
    }

    func applicationDidBecomeActive(_ application: UIApplication) {
        // Not called under iOS 13 - See SceneDelegate sceneDidBecomeActive
    }

    // MARK: UISceneSession Lifecycle

    @available(iOS 13.0, *)
    func application(_ application: UIApplication, configurationForConnecting connectingSceneSession: UISceneSession, options: UIScene.ConnectionOptions) -> UISceneConfiguration {
        // Called when a new scene session is being created.
        // Use this method to select a configuration to create the new scene with.
        return UISceneConfiguration(name: "Default Configuration", sessionRole: connectingSceneSession.role)
    }

    @available(iOS 13.0, *)
    func application(_ application: UIApplication, didDiscardSceneSessions sceneSessions: Set<UISceneSession>) {
        // Called when the user discards a scene session.
        // If any sessions were discarded while the application was not running, this will be called shortly after application:didFinishLaunchingWithOptions.
        // Use this method to release any resources that were specific to the discarded scenes, as they will not return.
    }
}

您的场景代表可能是:

@available(iOS 13.0, *)
class SceneDelegate: UIResponder, UIWindowSceneDelegate {
    var window: UIWindow?

    func scene(_ scene: UIScene, willConnectTo session: UISceneSession, options connectionOptions: UIScene.ConnectionOptions) {
        guard let windowScene = (scene as? UIWindowScene) else { return }

        let window = UIWindow(windowScene: windowScene)
        self.window = window

        if (user != nil && userSelfIdent != nil){
            let mainstoryboard:UIStoryboard = UIStoryboard(name: "Main", bundle: nil)
            let newViewcontroller:UIViewController = mainstoryboard.instantiateViewController(withIdentifier: "swrevealviewcontroller") as! SWRevealViewController
            window.rootViewController = newViewcontroller
            window.makeKeyAndVisible()
        }
    }

    func sceneDidDisconnect(_ scene: UIScene) {
        // Called as the scene is being released by the system.
    }

    func sceneDidBecomeActive(_ scene: UIScene) {
        // Not called under iOS 12 - See AppDelegate applicationDidBecomeActive
    }

    func sceneWillResignActive(_ scene: UIScene) {
        // Not called under iOS 12 - See AppDelegate applicationWillResignActive
    }

    func sceneWillEnterForeground(_ scene: UIScene) {
        // Not called under iOS 12 - See AppDelegate applicationWillEnterForeground
    }

    func sceneDidEnterBackground(_ scene: UIScene) {
        // Not called under iOS 12 - See AppDelegate applicationDidEnterBackground
    }
}

这篇关于即使添加了SceneDelegate并更新了Info.plist之后，Xcode 11黑屏上的iOS13的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！