添加 SceneDelegate 并更新 Info.plist 后黑屏

Question

我目前正在使用 Xcode 11、Target iOS 13.0（该应用程序适用于所有低于 iOS 12.1 至 12.4 的版本）的空白屏幕，我想让我的应用程序同时适用于 12.1 以上的 iOS 用户和目前正在获得的 13.0尽管将以下 UIWindowSceneDelegate 添加到我现有的项目和 App Manifest 中，但仍出现空白屏幕：

添加应用清单文件

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，它首先被调用并执行 didFinishLaunchWithOptions 方法。我想知道只有当我的 Target ios 小于 13.0 并在 13.0 之后调用 SceneDelegate 方法来初始化我的 rootViewController 时，我才能调用此方法？

@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            
        }
    }

Answer 1

我正在将一些示例代码从旧版 App Delegate 演示文稿移植到具有新 Scene Delegate 基础架构的新 Xcode 项目中。

即使在将代码移动到场景代理之后，我还是会出现黑屏。

问题在于我获取window 引用的方式。

使用新的 UIWindow(windowScene:) 初始化器而不是 initWithFrame:。

class SceneDelegate: UIResponder, UIWindowSceneDelegate {
    
    var window: UIWindow?
    
    func scene(_ scene: UIScene, willConnectTo session: UISceneSession, options connectionOptions: UIScene.ConnectionOptions) {
        
        // OLD: causes black screen
        self.window = UIWindow(frame: UIScreen.main.bounds)

        // NEW: works perfectly
        guard let windowScene = (scene as? UIWindowScene) else { return }
        self.window = UIWindow(windowScene: windowScene)
        
        let vc = UIStoryboard(name: "Main", bundle: nil).instantiateViewController(withIdentifier: "INITAL_VIEW_CONTROLLER")
        self.window?.rootViewController = vc
        self.window?.makeKeyAndVisible()
    }
    
}

Answer 2

轻松按照以下步骤操作：

1. 移除场景委托文件

2. 将以下代码添加到 AppDelegate.swift

    class AppDelegate: UIResponder, UIApplicationDelegate {
   
    var window: UIWindow?
    func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {
        return true
    }
   }
   

3. 从 .plist 文件中删除 Application Scene Manifest 行

Answer 3

使用 iOS 13 及更低版本运行的步骤：

1. 将部署目标更改为 iOS 12。

2. 将 AppDelegate 的方法替换为 iOS 12 开发应具备的方法。还要加上这个：

   var window: UIWindow?
   

3. 删除 SceneDelegate。

4. 删除 info.plist 中的应用程序场景清单。

它适用于 iOS 13 和更低的 iOS 版本

Answer 4

我在AppDelegate中注释了2个场景方法，然后就可以了 请检查我的截图

Answer 5

xcode 11.6 @ionic/react 电容器应用程序

更新时间：2020 年 7 月 22 日

我们在 TestFlight 也遇到了黑屏问题。 我们终于解决了。

检查 config.capacitor.json 看看你是否有本地主机， 删除服务器部分下的 URL.. 当我们运行发布时，我们（我）忘记了我们的 URL localhost 仍然存在，老实说，我不知道这可能是问题或从未想过要在那里检查， 我花了时间（几天）检查故事板建议。

Answer 6

请参考上图并在 AppDelegate 中添加该行。

Answer 7

当我遇到类似问题时，这是因为使用 Xcode 11.0 生成的单应用程序模板与使用 Xcode 11.2 构建的应用程序所需的模板不兼容。

所以我刚刚使用 Xcode 11.2 创建了一个新的 Single-Page-App，并将生成的 SceneDelegate 复制到使用 Xcode 11.0 创建的旧项目中。

在那之后，空白屏幕消失了，我的界面再次可见。

Answer 8

我被这个问题困住了，最后我解决了从情节提要中删除 searchDisplayController 引用的问题。

<searchDisplayController id="pWz-So-g6H">
                    <connections>
                        <outlet property="delegate" destination="Yci-sd-Mof" id="fjs-ah-jLs"/>
                        <outlet property="searchContentsController" destination="Yci-sd-Mof" id="gQN-1r-gti"/>
                        <outlet property="searchResultsDataSource" destination="Yci-sd-Mof" id="2Jf-lh-Ute"/>
                        <outlet property="searchResultsDelegate" destination="Yci-sd-Mof" id="Hap-SA-f02"/>
                    </connections>
                </searchDisplayController>

Answer 9

这里有几个问题。请务必阅读与应用生命周期相关的文档，其中说明了在 iOS 13 下的调用以及在 iOS 12 下的调用。

你可能还想看看我的支持 iOS 12 和 13 的Single View App template。

查看你的代码，这里是问题的总结：

AppDelegate：

• 如果应用在 iOS 12 或更早版本下运行，您应该只设置主窗口和根视图控制器。您需要在运行时检查这一点。
• func scene(_ scene: UIScene, willConnectTo session: UISceneSession, options connectionOptions: UIScene.ConnectionOptions) 方法不应在应用委托中。
• 不直接相关，但在应用启动时从不休眠。删除 Thread.sleep(forTimeInterval: 3.0) 行。用户希望使用您的应用程序，而不是盯着启动屏幕超过必要的时间。在应用启动时阻塞主线程可能会导致您的应用被终止。

场景代理：

• 这基本没问题，但没有理由使用 guard let _ = (scene as? UIWindowScene) else { return } 行，尤其是因为它位于 if let 内，已经进行了检查。
• 您似乎没有使用 SwiftUI，因此请删除该导入。

我会将您的应用委托更新为更像这样：

@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.
    }
}

您的场景委托可能是：

@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
    }
}