Swift 4 - 如何从当前视图控制器设置和显示新的根视图控制器

Question

为此苦苦挣扎了几天...

我已经在 didFinishLaunchingWithOptions 中从 AppDelegate 设置了一个 rootVC，这工作正常。

现在 rootVC 我想要那个，如果满足某些条件，例如。 if x=y 设置并显示了一个新的 rootVC。

我的堆栈溢出了很长时间，找到了不同的解决方案，但是 none 正在工作。

下面是编译，执行，断点检查，app里什么也没有

animated    Bool    false   
self    Regional2.IrelandViewController 0x0000000102b0ff30
newViewController   Regional2.IrelandMain   0x0000000102d0d300
customViewControllersArray  NSArray 0x00000001c000b620
ObjectiveC.NSObject NSObject    
Exception State Registers       
far unsigned long   0x00000001b0a7ba78
esr unsigned int    0x92000007
exception   unsigned int    0x00000000
Floating Point Registers        
General Purpose Registers

和这段代码。 . .

override func viewDidAppear(_ animated: Bool) {
    super.viewDidAppear(animated)

    let newViewController = self.storyboard?.instantiateViewController(withIdentifier: "IrelandMain") as! IrelandMain

    let customViewControllersArray : NSArray = [newViewController]

    self.navigationController?.viewControllers = customViewControllersArray as! [UIViewController]
    self.navigationController?.pushViewController(newViewController, animated: true)

}

请注意 navigationController show 产生相同的输出。没有任何变化。

Answer 1

该代码对我有用。它只是替换了整个 UIWindow。

当我试图只替换 rootViewController 时，它成功了，但它创建了另一个（所以我在视图层次结构中有两个加载的 viewController）

if let appDelegate = UIApplication.shared.delegate as? AppDelegate {
    // If we only reloads the rootViewController than the main window has 2 subviews
    // The older cannot be removed and the new can be removed.
    // The workaround I found is to replace the whole UIWindow with new one
    let root = UIStoryboard(name: "Main", bundle: Bundle.main).instantiateInitialViewController()
    let newWindow = UIWindow()
    appDelegate.replaceWindow(newWindow)
    newWindow.rootViewController = root
}

并在您的 AppDelegate 中

func replaceWindow(_ newWindow: UIWindow) {
    if let oldWindow = window {
        newWindow.frame = oldWindow.frame
        newWindow.windowLevel = oldWindow.windowLevel
        newWindow.screen = oldWindow.screen
        newWindow.isHidden = false
        window = newWindow
        oldWindow.removeFromSuperview()
    }
}

Swift 4 - 如何从当前视图控制器设置和显示新的根视图控制器

Swift 4 - How to set and show a new root view controller from current view controller

viewcontroller

ios

swift