Extra bottom space/padding on iPhone X?

Question

On the iPhone X in portrait mode, if you set a bottom constraint to safe area to 0, you will end up with an extra space at the bottom of the screen. How do you get programmatically the height of this extra padding ?

I managed to manually determine the height of this padding which is 34 and here is how I managed to implement it with iPhone X detection:

Swift 4.0 and Xcode 9.0

if UIDevice().userInterfaceIdiom == .phone
{
    switch UIScreen.main.nativeBounds.height
    {
        case 2436: //iPhone X
        self.keyboardInAppOffset.constant = -34.0
        default:
        self.keyboardInAppOffset.constant = 0
    }
}

Is there a cleaner way to detect the height of this padding ?

Answer 1

In iOS 11, views have a safeAreaInsets property. If you get the bottom property of these insets you can get the height of the bottom padding while on iPhone X:

if #available(iOS 11.0, *) {
    let bottomPadding = view.safeAreaInsets.bottom
    // ...
}

(likewise for the top padding with status bar)