How to get RGB values from UIColor?

Question

I\'m creating a color object using the following code.

curView.backgroundColor = [[UIColor alloc] initWithHue:229 saturation:40 brightness:75 alpha:1];
         


        

Answer 1

SWIFT 3 & 4

I found that cgColor.components would not always return 4 color values, so I changed this so it gets them from a CIColor wrapper

extension UIColor {
    var redValue: CGFloat{ return CIColor(color: self).red }
    var greenValue: CGFloat{ return CIColor(color: self).green }
    var blueValue: CGFloat{ return CIColor(color: self).blue }
    var alphaValue: CGFloat{ return CIColor(color: self).alpha }
}

SWIFT 2

extension UIColor {
    var red: CGFloat{ return CGColorGetComponents(self.CGColor)[0] }
    var green: CGFloat{ return CGColorGetComponents(self.CGColor)[1] }
    var blue: CGFloat{ return CGColorGetComponents(self.CGColor)[2] }
    var alpha: CGFloat{ return CGColorGetComponents(self.CGColor)[3] }
}

It's not the most efficient way so I wouldn't go using this where a view will be constantly re-drawn.