Get safe area inset top and bottom heights

Question

On the new iPhone X, what would be the most proper way to get both top and bottom height for the unsafe areas?

Answer 1

In iOS 11 there is a method that tells when the safeArea has changed.

override func viewSafeAreaInsetsDidChange() {
    super.viewSafeAreaInsetsDidChange()
    let top = view.safeAreaInsets.top
    let bottom = view.safeAreaInsets.bottom
}

Answer 2

Swift 4

if let window = UIApplication.shared.windows.first {
    
    let topPadding = window.safeAreaInsets.top
    let bottomPadding = window.safeAreaInsets.bottom
    
}

Use from class

class fitToTopInsetConstraint: NSLayoutConstraint {
    
    override func awakeFromNib() {
        
        if let window = UIApplication.shared.windows.first {
            
            let topPadding = window.safeAreaInsets.top
            
            self.constant += topPadding
            
        }
        
    }
}

class fitToBottomInsetConstraint: NSLayoutConstraint {
    
    override func awakeFromNib() {
        
        if let window = UIApplication.shared.windows.first {
            
            let bottomPadding = window.safeAreaInsets.bottom
            
            self.constant += bottomPadding
            
        }
        
    }
}

You will see safe area padding when you build your application.

Answer 3

safeAreaLayoutGuide When the view is visible onscreen, this guide reflects the portion of the view that is not covered by navigation bars, tab bars, toolbars, and other ancestor views. (In tvOS, the safe area reflects the area not covered the screen's bezel.) If the view is not currently installed in a view hierarchy, or is not yet visible onscreen, the layout guide edges are equal to the edges of the view.

Then to get the height of the red arrow in the screenshot it's:

self.safeAreaLayoutGuide.layoutFrame.size.height

Answer 4

I'm working with CocoaPods frameworks and in case UIApplication.shared is unavailable then I use safeAreaInsets in view's window:

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

Answer 5

To get the height between the layout guides you just do

let guide = view.safeAreaLayoutGuide
let height = guide.layoutFrame.size.height

So full frame height = 812.0, safe area height = 734.0

Below is the example where the green view has frame of guide.layoutFrame

Answer 6

Swift 5, Xcode 11.4

`UIApplication.shared.keyWindow` 

It will give deprecation warning. ''keyWindow' was deprecated in iOS 13.0: Should not be used for applications that support multiple scenes as it returns a key window across all connected scenes' because of connected scenes. I use this way.

extension UIView {

    var safeAreaBottom: CGFloat {
         if #available(iOS 11, *) {
            if let window = UIApplication.shared.keyWindowInConnectedScenes {
                return window.safeAreaInsets.bottom
            }
         }
         return 0
    }

    var safeAreaTop: CGFloat {
         if #available(iOS 11, *) {
            if let window = UIApplication.shared.keyWindowInConnectedScenes {
                return window.safeAreaInsets.top
            }
         }
         return 0
    }
}

extension UIApplication {
    var keyWindowInConnectedScenes: UIWindow? {
        return windows.first(where: { $0.isKeyWindow })
    }
}