ViewController 未从 iOS 13.0 版本开始加载

Question

In iOS 13, I was unable to load the TabBarViewController . Below the iOS 13.0 version, it's working fine.

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
    }
}

I manually included SceneDelegate inside my project, does it have any impact on this?

Your solution should work from version iOS 13.0 onwards.

Answer 1

as commented before since iOS 13 sceneDelegate is introduced to handle multiple scene apps so if you have Scene delegate file then you must rewrite the function as this to use the window property in the scene delegate since is removed from AppDelegate.

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
    }
} 

}