Gradient color effect on UIView in iOS 10 Swift 2.3 Xcode 8 - ios10

Question

I am trying to achieve a gradient color on a UIView or button with two color black which fades out to clear color or white color (please see image).
I have tried using different combinations of white color, clear color; experimenting with alpha as well. I have also set the locations property as can be seen in below code but I am not able to achieve desired results.
Can anyone tell me where I am wrong. :)
let colorClear = UIColor.clearColor().CGColor
let colorLeft = UIColor(red: 255.0/255.0, green: 255.0/255.0, blue: 255.0/255.0, alpha: 0.9).CGColor
let colorRight = UIColor(red: 0.0/255.0, green: 0.0/255.0, blue: 0.0/255.0, alpha: 1.0).CGColor
let gradientLayer = CAGradientLayer()
gradientLayer.colors = [colorLeft, colorRight]
gradientLayer.locations = [ 0.1, 0.9]
gradientLayer.frame = self.createAccountView.bounds
gradientLayer.startPoint = CGPoint(x:0.0, y:0.5)
gradientLayer.endPoint = CGPoint(x:1.0, y:0.5)
createAccountView.layer.addSublayer(gradientLayer)
createAccountView.layer.masksToBounds = true
The desired result is the one in which black color transitions to a faded one.
I have already tried setting both colors as black and the color1 with an alpha.
I have already tried commenting locations property.

Answer 1

you should set gradientLayer.frame in viewDidLayoutSubviews().
Like this:
class ViewController: UIViewController {
let gradientLayer = CAGradientLayer()
override func viewDidLoad() {
let colorClear = UIColor.clearColor().CGColor
let colorLeft = UIColor(red: 255.0/255.0, green: 255.0/255.0, blue: 255.0/255.0, alpha: 0.9).CGColor
let colorRight = UIColor(red: 0.0/255.0, green: 0.0/255.0, blue: 0.0/255.0, alpha: 1.0).CGColor
self.gradientLayer.colors = [colorLeft, colorRight]
self.gradientLayer.locations = [ 0.1, 0.9]
self.gradientLayer.startPoint = CGPoint(x:0.0, y:0.5)
self.gradientLayer.endPoint = CGPoint(x:1.0, y:0.5)
createAccountView.layer.addSublayer(self.gradientLayer)
createAccountView.layer.masksToBounds = true
}
override viewDidLayoutSubviews() {
super.viewDidLayoutSubViews()
self.gradientLayer.frame = self.createAccountView.bounds
}