Get random UIColor with Swift

UIColor+Random.swift

/*
UIColor class method that returns a random color. All parameters are optional.
*/

import UIKit

extension UIColor{
    class func randomColor(hue:CGFloat? = ( CGFloat( CGFloat(arc4random()) % 256 / 256.0 ) ),
        saturation:CGFloat? = ( CGFloat( CGFloat(arc4random()) % 128 / 256.0 ) + 0.5 ),
        brightness:CGFloat? = ( CGFloat( CGFloat(arc4random()) % 128 / 256.0 ) + 0.5 ),
        alpha:CGFloat? = CGFloat(1.0)) -> UIColor{
            return UIColor(hue: hue!, saturation: saturation!, brightness: brightness!, alpha: alpha!);
    }
}