Check out example codes for "swift has Top Notch". It will help you in understanding the concepts better.

Code Example 1

extension UIDevice {
    /// Returns `true` if the device has a notch
    var hasNotch: Bool {
        guard #available(iOS 11.0, *), let window = UIApplication.shared.windows.filter({$0.isKeyWindow}).first else { return false }
        if UIDevice.current.orientation.isPortrait {
            return window.safeAreaInsets.top >= 44
        } else {
            return window.safeAreaInsets.left > 0 || window.safeAreaInsets.right > 0
        }
    }
}

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