swift - 为什么在没有root View Controller 的情况下hidesBottomBarWhenPushed不起作用？

按下视图控制器并隐藏底部选项卡栏，如下所示：

let myViewController = self.storyboard?.instantiateViewController(withIdentifier: MyViewController) as! MyViewController
myViewController.hidesBottomBarWhenPushed = true
navigationController?.pushViewController(myViewController, animated: true)

那很好。
但是，当我在按下前更改根视图控制器时，底部栏不会隐藏。

// Change the root view controller
let firstRootViewController = UIApplication.shared.keyWindow!.rootViewController
UIApplication.shared.keyWindow!.rootViewController = secondRootViewController

// Push view on stack of navigation controller which is a child of firstRootViewController
let myViewController = self.storyboard?.instantiateViewController(withIdentifier: MyViewController) as! MyViewController
myViewController.hidesBottomBarWhenPushed = true
navigationController?.pushViewController(myViewController, animated: true)

// Some more things happen...

// Switch back to previous root view controller
UIApplication.shared.keyWindow!.rootViewController = firstRootViewController

结果是导航控制器正确地按下了myViewController，但底部的条是可见的，好像忽略了参数hidesBottomBarWhenPushed。
这里怎么了？

最佳答案

解决方案是不更改根视图控制器，而只将视图添加到keyWindow：

// Add another view on top of all views
UIApplication.shared.keyWindow?.addSubView(self.view)

// Push view on stack of navigation controller which is a child of firstRootViewController
let myViewController = self.storyboard?.instantiateViewController(withIdentifier: MyViewController) as! MyViewController
myViewController.hidesBottomBarWhenPushed = true
navigationController?.pushViewController(myViewController, animated: true)

// Some more things happen...

// Remove topmost view
self.view.removeFromSuperview()

关于swift - 为什么在没有root View Controller 的情况下hidesBottomBarWhenPushed不起作用？，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/43426238/