如何正确地对iOS 11中的状态栏添加模糊效果，而无需警告

Question

我曾经在状态栏上添加模糊效果，并具有以下代码：

// 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

即使对于Xcode 9，它也起作用。但是，最后两行开始发出警告，因为Xcode 9：

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

遵循警告，如果我将 topLayoutGuide更改为建议的值，结果不正确（所有屏幕都是空白）。

如何正确地对iOS 11中的状态栏添加模糊效果？

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