注意，如果你想在全屏中添加视图，那么只能使用下面的代码

添加这些UIViewController的扩展

public extension UIViewController {
   internal func makeViewAsFullScreen() {
      var viewFrame:CGRect = self.view.frame
      if viewFrame.origin.y > 0 || viewFrame.origin.x > 0 {
        self.view.frame = UIScreen.main.bounds
      }
   }
}

继续正常的子视图添加过程

现在用于添加UIViewController的viewDidAppear

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

     self.makeViewAsFullScreen()
}

You need to add a subview to the first window with the UITextEffectsWindow type. To the first, because custom keyboards add their UITextEffectsWindow, and if you add a subview to it this won't work correctly. Also, you cannot add a subview to the last window because the keyboard, for example, is also a window and you can`t present from the keyboard window. So the best solution I found is to add subview (or even push view controller) to the first window with UITextEffectsWindow type, this window covers accessory view, navbar - everything.

let myView = MyView()
myView.frame = UIScreen.main.bounds

guard let textEffectsWindow = NSClassFromString("UITextEffectsWindow") else { return }
let window = UIApplication.shared.windows.first { window in
    window.isKind(of: textEffectsWindow)
}
window?.rootViewController?.view.addSubview(myView)

在Swift 4.2和Xcode 10中

var spinnerView: UIView? //This is your view

spinnerView = UIView(frame: CGRect(x: 0, y: 0, width: UIScreen.main.bounds.size.width, height: UIScreen.main.bounds.size.height))
//Based on your requirement change width and height like self.view.bounds.size.width
spinnerView?.backgroundColor = UIColor.black.withAlphaComponent(0.6)
//        self.view.addSubview(spinnerView)
let currentWindow: UIWindow? = UIApplication.shared.keyWindow
currentWindow?.addSubview(spinnerView!)

在Objective C中

这是你的视图

self.spinnerView = [[UIView alloc]initWithFrame:CGRectMake(0, 0, UIScreen.mainScreen.bounds.size.width, UIScreen.mainScreen.bounds.size.height)];  
//Based on your requirement change width and height like self.view.bounds.size.width
self.spinnerView.backgroundColor = [[UIColor blackColor] colorWithAlphaComponent:0.6];
// [self.view addSubview:self.spinnerView];
UIWindow *currentWindow = [UIApplication sharedApplication].keyWindow;
[currentWindow addSubview:self.spinnerView];

这可以工作在纵向或横向模式。

更简单的代码是:

yourViewName.layer.zPosition = 1//Change your view name

@Nam的答案是伟大的，如果你只是想显示你的自定义视图，但如果你的自定义视图需要用户交互，你需要禁用导航栏的交互。

self.navigationController.navigationBar.layer.zPosition = -1
self.navigationController.navigationBar.isUserInteractionEnabled = false

就像Nam的回答中所说的，不要忘记逆转这些变化:

self.navigationController.navigationBar.layer.zPosition = 0
self.navigationController.navigationBar.isUserInteractionEnabled = true

你可以用一个扩展更好的方式做到这一点:

extension UINavigationBar {
    func toggle() {
        if self.layer.zPosition == -1 {
            self.layer.zPosition = 0
            self.isUserInteractionEnabled = true
        } else {
            self.layer.zPosition = -1
            self.isUserInteractionEnabled = false
        }
    }
}

就像这样简单地使用它:

self.navigationController.navigationBar.toggle()

你可以通过将你的视图直接添加到keyWindow来实现:

UIView *myView = /* <- Your custom view */;
UIWindow *currentWindow = [UIApplication sharedApplication].keyWindow;
[currentWindow addSubview:myView];

更新—适用于Swift 4.1及以上

let currentWindow: UIWindow? = UIApplication.shared.keyWindow
currentWindow?.addSubview(myView)

iOS13及以上更新

已弃用keyWindow。你应该使用以下方法:

UIApplication.shared.windows.first(where: { $0.isKeyWindow })?.addSubview(myView)

我将使用一个UIViewController子类，包含一个“容器视图”，它嵌入了你的其他视图控制器。 然后，您将能够在容器视图中添加导航控制器(例如使用嵌入关系segue)。

参见实现容器视图控制器