或者使用SwiftUI GeometryReader api。

struct V: View {
    var body: some View {
        GeometryReader { geometry in
            Text("\(geometry.safeAreaInsets.top)")
            Text("\(geometry.safeAreaInsets.bottom)")
        }
    }
}

代码可能不起作用，但却说明了这个想法。

更全面的方法

  import SnapKit

  let containerView = UIView()
  containerView.backgroundColor = .red
  self.view.addSubview(containerView)
  containerView.snp.remakeConstraints { (make) -> Void in
        make.width.top.equalToSuperView()
        make.top.equalTo(self.view.safeArea.top)
        make.bottom.equalTo(self.view.safeArea.bottom)
  }




extension UIView {
    var safeArea: ConstraintBasicAttributesDSL {
        if #available(iOS 11.0, *) {
            return self.safeAreaLayoutGuide.snp
        }
        return self.snp
    }


    var isIphoneX: Bool {

        if #available(iOS 11.0, *) {
            if topSafeAreaInset > CGFloat(0) {
                return true
            } else {
                return false
            }
        } else {
            return false
        }

    }

    var topSafeAreaInset: CGFloat {
        let window = UIApplication.shared.keyWindow
        var topPadding: CGFloat = 0
        if #available(iOS 11.0, *) {
            topPadding = window?.safeAreaInsets.top ?? 0
        }

        return topPadding
    }

    var bottomSafeAreaInset: CGFloat {
        let window = UIApplication.shared.keyWindow
        var bottomPadding: CGFloat = 0
        if #available(iOS 11.0, *) {
            bottomPadding = window?.safeAreaInsets.bottom ?? 0
        }

        return bottomPadding
    }
}

这里有一个简单的答案，可以找到所有iphone的安全区域高度

let window = UIApplication.shared.windows[0]

let SafeAreaHeight = window.safeAreaLayoutGuide.layoutFrame.size.height

这适用于整个视图生命周期，在Swift中是一个简单的两行解决方案:

let top    = UIApplication.shared.windows[0].safeAreaInsets.top
let bottom = UIApplication.shared.windows[0].safeAreaInsets.bottom

我个人需要它在viewDidLoad和view中。safeAreaInsets还没有计算。

这里有一个基于其他答案的免费函数，当你的rootController从任何地方布局时，它都应该是可调用的。你可以把它当做一个独立的函数。

    func safeAreaInsets() -> UIEdgeInsets? {
    (UIApplication
        .shared
        .keyWindow?
        .rootViewController)
        .flatMap {
            if #available(iOS 11.0, *) {
                return $0.view.safeAreaInsets
            } else {
                return .init(
                    top: $0.topLayoutGuide.length,
                    left: .zero,
                    bottom: $0.bottomLayoutGuide.length,
                    right: .zero
                )
            }
        }
}

我正在使用CocoaPods框架和UIApplication。shared不可用，然后我在视图窗口中使用safeAreaInsets:

if #available(iOS 11.0, *) {
    let insets = view.window?.safeAreaInsets
    let top = insets.top
    let bottom = insets.bottom
}