gistfile1.swift

extension UIColor {

    // Creates a UIColor from a Hex string.
    class func colorWithHexString (hex:String) -> UIColor {

        var cString:String = hex.stringByTrimmingCharactersInSet(NSCharacterSet.whitespaceAndNewlineCharacterSet()).uppercaseString

        if (cString.hasPrefix("#")) {
            cString = cString.substringFromIndex(advance(cString.startIndex, 1))
        }

        if (countElements(cString) != 6) {
            return UIColor.grayColor()
        }

        var rString = cString.substringToIndex(advance(cString.startIndex, 2))
        var gString = cString.substringFromIndex(advance(cString.startIndex, 2)).substringToIndex(advance(cString.startIndex, 2))
        var bString = cString.substringFromIndex(advance(cString.startIndex, 4)).substringToIndex(advance(cString.startIndex,2))

        var r:CUnsignedInt = 0, g:CUnsignedInt = 0, b:CUnsignedInt = 0;
        NSScanner.scannerWithString(rString).scanHexInt(&r)
        NSScanner.scannerWithString(gString).scanHexInt(&g)
        NSScanner.scannerWithString(bString).scanHexInt(&b)

        let floatRed = CGFloat(r) / 255.0
        let floatGreen = CGFloat(g) / 255.0
        let floatBlue = CGFloat(b) / 255.0
        let floatAlpha = CGFloat(1)

        return UIColor(red: floatRed, green: floatGreen, blue: floatBlue, alpha: floatAlpha)
    }
}

Works in Beta 6