Swift UIColor Extensions

Swift UIColor Extensions

extension UIColor {
    class func fromHexString(hex:String) -> UIColor {
        let hex = hex.stringByTrimmingCharactersInSet(NSCharacterSet.alphanumericCharacterSet().invertedSet)
        var int = UInt32()
        NSScanner(string: hex).scanHexInt(&int)
        let a, r, g, b: UInt32
        switch hex.characters.count {
        case 3: // RGB (12-bit)
            (a, r, g, b) = (255, (int >> 8) * 17, (int >> 4 & 0xF) * 17, (int & 0xF) * 17)
        case 6: // RGB (24-bit)
            (a, r, g, b) = (255, int >> 16, int >> 8 & 0xFF, int & 0xFF)
        case 8: // ARGB (32-bit)
            (a, r, g, b) = (int >> 24, int >> 16 & 0xFF, int >> 8 & 0xFF, int & 0xFF)
        default:
            (a, r, g, b) = (1, 1, 1, 0)
        }
        return UIColor(red: CGFloat(r) / 255, green: CGFloat(g) / 255, blue: CGFloat(b) / 255, alpha: CGFloat(a) / 255)
    }
    
    class func makeGradient(one:UIColor,two:UIColor,frame:CGRect) -> CAGradientLayer {
        let gradient = CAGradientLayer()
        let colour_array = [one.CGColor,two.CGColor]
        gradient.frame = frame
        gradient.colors = colour_array
        return gradient
    }
    
    func lighterColor(percent : Double) -> UIColor {
        return colorWithBrightnessFactor(CGFloat(1 + percent));
    }
    
    func darkerColor(percent : Double) -> UIColor {
        return colorWithBrightnessFactor(CGFloat(1 - percent));
    }
    
    func colorWithBrightnessFactor(factor: CGFloat) -> UIColor {
        var hue : CGFloat = 0
        var saturation : CGFloat = 0
        var brightness : CGFloat = 0
        var alpha : CGFloat = 0
        
        if getHue(&hue, saturation: &saturation, brightness: &brightness, alpha: &alpha) {
            return UIColor(hue: hue, saturation: saturation, brightness: brightness * factor, alpha: alpha)
        } else {
            return self;
        }
    }
}