Rainbow color gradient written in Swift2.2

RainbowGradient.swift

func insertGradientLayer(view: UIView) {
    let color1 = UIColor.redColor()
    let color2 = UIColor(red: 255, green: 165, blue: 0, alpha: 1.0)
    let color3 = UIColor.yellowColor()
    let color4 = UIColor(red: 0, green: 128, blue: 0, alpha: 1.0)
    let color5 = UIColor.cyanColor()
    let color6 = UIColor.blueColor()
    let color7 = UIColor.purpleColor()
    let fromColors = [color1.CGColor, color2.CGColor, color3.CGColor, color4.CGColor, color5.CGColor, color6.CGColor, color7.CGColor]
    let toColors = fromColors.reverse()
    
    let animation = CABasicAnimation(keyPath: "colors")
    animation.duration = 1.0
    animation.repeatCount = 99999
    // animation.autoreverses = true
    // animation.timingFunction = CAMediaTimingFunction(name: kCAMediaTimingFunctionEaseInEaseOut)
    animation.fromValue = fromColors
    animation.toValue = Array(toColors)
    
    let gradient = CAGradientLayer()
    gradient.frame = view.bounds
    gradient.colors = fromColors
    gradient.addAnimation(animation, forKey: "colors")
    
    view.layer.insertSublayer(gradient, atIndex: 0)
}

.CGColorを忘れると、「Error: CGColorSpaceIsUncalibrated」で死ぬ

Wow, praise the Internet! Man, you saved me a ton of nerves even though I don't understand japanese. Just googled for CGColorSpaceIsUncalibrated error and stumbled upon your comment. Used google translate to check what you've written, then checked my code and TADA! Turned out I forgot to add .cgColor in couple of places so my app crashed during animation.