UIColor hex utilities

UIColor.swift

extension UIColor {
    convenience init(hexNumber: UInt32) {
        let red = CGFloat(hexNumber >> 16 & 0xFF) / 255
        let green = CGFloat(hexNumber >> 8 & 0xFF) / 255
        let blue = CGFloat(hexNumber & 0xFF) / 255
        self.init(red: red, green: green, blue: blue, alpha: 1)
    }

    convenience init?(hexString: String) {
        guard let number = UInt32(hexString, radix: 16) else {
            return nil
        }
        self.init(hexNumber: number)
    }
}