UIColor init extension with hexadecimal

ColorInitWithHexString.swift

extension UIColor {
    convenience init?(hex:String){
        var cString:String = hex.trimmingCharacters(in: CharacterSet.whitespacesAndNewlines).uppercased()
        if (cString.hasPrefix("#")) {
            let index = cString.index(cString.startIndex, offsetBy: 1)
            cString = cString.substring(from: index)
        }
        
        if (cString.characters.count != 6) {
            return nil
        }
        
        var rgbValue:UInt32 = 0
        Scanner(string: cString).scanHexInt32(&rgbValue)
        
        self.init(
            red: CGFloat((rgbValue & 0xFF0000) >> 16) / 255.0,
            green: CGFloat((rgbValue & 0x00FF00) >> 8) / 255.0,
            blue: CGFloat(rgbValue & 0x0000FF) / 255.0,
            alpha: CGFloat(1.0)
        )

    }
}

Greaaat!