ViewController 无法从 iOS 13.0 版本开始加载

Question

在 iOS 13 中，我无法加载 TabBarViewController。在 iOS 13.0 版本以下，它工作正常。

public static func updateRootVC(){

    var rootVC = UIViewController()
    let appDelegate = UIApplication.shared.delegate as! AppDelegate

    if(status == true){

        let tabBarController  = UIStoryboard(name: AppStoryboard.dashboard.rawValue, bundle: nil).instantiateViewController(withIdentifier: "TabBarController") as! TabBarController
        appDelegate.window?.rootViewController = tabBarController

    }

    else{
        let welcomeViewController = UIStoryboard(name: AppStoryboard.main.rawValue, bundle: nil).instantiateViewController(withIdentifier: "WelcomeViewController") as! WelcomeViewController
        rootVC = UINavigationController.init(rootViewController: welcomeViewController)
        rootVC.addChild(welcomeViewController)
        appDelegate.window?.rootViewController = rootVC
    }
}

我手动将 SceneDelegate 包含在我的项目中，它对此有什么影响吗？

您的解决方案应该从 iOS 13.0 版本开始工作。

Answer 1

正如之前评论的那样，因为 iOS 引入了 13 sceneDelegate 来处理多个场景应用程序，所以如果您有场景委托文件，那么您必须将函数重写为这样才能使用 window 属性在场景委托中，因为已从 AppDelegate 中删除。

public static func updateRootVC(){
var rootVC = UIViewController()
let appDelegate = UIApplication.shared.delegate as! AppDelegate
if(status == true){
    let tabBarController  = UIStoryboard(name: AppStoryboard.dashboard.rawValue, bundle: nil).instantiateViewController(withIdentifier: "TabBarController") as! TabBarController
    if #available(iOS 13, *) {
        UIApplication.shared.windows.first?.rootViewController = tabBarController
        UIApplication.shared.windows.first?.makeKeyAndVisible()
    }else{        
        appDelegate.window?.rootViewController = tabBarController
    }      
}else{
    let welcomeViewController = UIStoryboard(name: AppStoryboard.main.rawValue, bundle: nil).instantiateViewController(withIdentifier: "WelcomeViewController") as! WelcomeViewController
    rootVC = UINavigationController.init(rootViewController: welcomeViewController)
    rootVC.addChild(welcomeViewController)
    if #available(iOS 13, *) {
        UIApplication.shared.windows.first?.rootViewController = rootVC
        UIApplication.shared.windows.first?.makeKeyAndVisible()

    }else{        
        appDelegate.window?.rootViewController = tabBarController
    }
}

}

ViewController 无法从 iOS 13.0 版本开始加载

ViewController not loading from iOS 13.0 version onwards

ios

appdelegate

swift

ios13