Curved UINavigationBar written in Swift 4.0
Copy all extensions into your project
In your view controller add the following line (adjust properties as needed)
addCurvedNavigationBar(backgroundColor: .white, curveRadius: 17.0, shadowColor: .darkGray, shadowRadius: 4.0, heightOffset: 0.0)
If you need to change color, use the following
updateCurvedNavigationBarBackgroundColor(color: .red)