ios - 如何在没有警告的情况下正确地在 iOS 11 状态栏上添加模糊效果？

Question

我曾经使用以下代码在状态栏上添加模糊效果:

// Add blur effect on status bar
let blurEffect = UIBlurEffect(style: UIBlurEffectStyle.extraLight)
let blurEffectView = UIVisualEffectView(effect: blurEffect)
blurEffectView.translatesAutoresizingMaskIntoConstraints = false
view.addSubview(blurEffectView)
blurEffectView.leadingAnchor.constraint(equalTo: view.leadingAnchor).isActive = true
blurEffectView.trailingAnchor.constraint(equalTo: view.trailingAnchor).isActive = true
blurEffectView.topAnchor.constraint(equalTo: self.topLayoutGuide.topAnchor).isActive = true
blurEffectView.bottomAnchor.constraint(equalTo: self.topLayoutGuide.bottomAnchor).isActive = true

它从 Xcode 6 或 7 开始工作，甚至对于 Xcode 9。但是，最后两行从 Xcode 9 开始发出警告:

'topLayoutGuide' was deprecated in iOS 11.0: Use view.safeAreaLayoutGuide.topAnchor instead of topLayoutGuide.bottomAnchor

按照警告，如果我将 topLayoutGuide 更改为建议值，结果不正确(所有屏幕都是空白)。

如何在 iOS 11 中正确添加状态栏模糊效果而不出现警告？

Answer 1

blurEffectView.leadingAnchor.constraint(equalTo: view.leadingAnchor).isActive = true
blurEffectView.widthAnchor.constraint(equalTo: view.widthAnchor).isActive = true
blurEffectView.topAnchor.constraint(equalTo: view.topAnchor).isActive = true
blurEffectView.bottomAnchor.constraint(equalTo: view.safeAreaLayoutGuide.topAnchor).isActive = true