UIWindow叠加层不可见

Question

在IOS应用程序中添加一个覆盖窗口到UIWindow键。 但是，新的叠加UIWindow似乎无处可见。

基于lldb：

，它似乎已成功添加

(lldb) po UIApplication.shared.windows
▿ 2 elements
  - 0 : <UIWindow: 0x7fdfd3d0aec0; frame = (0 0; 375 667); gestureRecognizers = <NSArray: 0x60800004d680>; layer = <UIWindowLayer: 0x608000220980>>
  - 1 : <UIWindow: 0x7fdfd3c0d010; frame = (0 0; 375 667); gestureRecognizers = <NSArray: 0x60000004c9c0>; layer = <UIWindowLayer: 0x6000002216e0>>

在调试中，

override func viewDidLoad() {
    super.viewDidLoad()
    // Do any additional setup after loading the view, typically from a nib.

    let vc = UIViewController()
    vc.view.backgroundColor = UIColor.blue

    let window = UIWindow()
    window.frame = self.view.bounds
    window.backgroundColor = UIColor.blue
    window.windowLevel = UIWindowLevelStatusBar
    window.rootViewController = vc
    window.isHidden = false
}

会欣赏任何提示/帮助 感谢

Answer 1

退出viewDidLoad()方法后，您的窗口将被取消分配。您需要强烈保留第二个窗口。