How to get RGB values from UIColor?

In iOS 5 you could use:

CGFloat red = 0.0, green = 0.0, blue = 0.0, alpha =0.0;[multipliedColor getRed:&red green:&green blue:&blue alpha:&alpha];

const CGFloat *colors = CGColorGetComponents( curView.backgroundColor.CGColor );

These links provide further details:

• UIColor Reference
• CGColorGetComponents reference

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.