Background colour of UIVIew inside UIPickerView does not set properly - ios

Question

I am trying to implement a UIPickerView with custom design. I've taken a UIVIew inside a UIPickerView and a label inside my UIVIew. Color of my picker background is black and Now I am trying to apply white background color to UIVIew and label inside View. But the colour is not what exact I want. I want pure white colour but it's returning gray. Can anyone help me for this?
Here is my code and output:
if pickerView == pkr1 {
let myView = UIView(frame: CGRect(x: 5, y: 0, width: pickerView.bounds.width - 10, height: Utilities.isDeviceiPad() ? 80.0 : 60.0))
myView.backgroundColor = UIColor.white
myView.isOpaque = false
let myLabel = UILabel(frame: CGRect(x: 5, y: 0, width: myView.bounds.width - 10, height: myView.frame.height))
myLabel.text = arrTemp[row]
// myLabel.center.y = myView.center.y
myLabel.textAlignment = .center
myLabel.numberOfLines = 2
myLabel.backgroundColor = UIColor.white
myLabel.alpha = CGFloat(1)
myLabel.lineBreakMode = NSLineBreakMode.byTruncatingTail
myView.addSubview(myLabel)
return myView
}
Output:

Answer 1

The reason why the selected view is transparent is that UIPickerView subview, that holds all the content, uses CAGradientLayer as a mask to achieve the depth effect. For some reason, Apple decided to make the selected view transparent as well. We can't simply rid of that mask because we will lose that fancy effect. So we need to figure out more about that gradient.
Here is how this gradient looks. I've added the alpha channel values so you could see how this gradient behave.
As you can see, it has 6 colors and everything is fine except the two values in the middle. They are 0.8 instead of 1.0, that what makes you selected view transparent.
This is a very bad approach and I strongly do not recommend do that but if you need to make your selected item opaque no matter what, you can simply create a subclass of you UIPickerView and change the gradient like that.
class MyPickerView: UIPickerView {
override init(frame: CGRect) {
super.init(frame: frame)
}
required init?(coder aDecoder: NSCoder) {
super.init(coder: aDecoder)
}
override func layoutSubviews() {
super.layoutSubviews()
self.changeGradientLayer()
}
func changeGradientLayer() {
guard let sublayers = self.subviews.first?.layer.sublayers else { return }
for case let sublayer as CAGradientLayer in sublayers {
sublayer.colors = [UIColor.black.withAlphaComponent(0).cgColor,
UIColor.black.withAlphaComponent(0.71).cgColor,
UIColor.black.withAlphaComponent(1.0).cgColor,
UIColor.black.withAlphaComponent(1.0).cgColor,
UIColor.black.withAlphaComponent(0.71).cgColor,
UIColor.black.withAlphaComponent(0).cgColor]
}
}
}
Hope it helps you.

Answer 2

Please add your view in picker view by below method and check it...hope it will work..
func pickerView(pickerView: UIPickerView, viewForRow row: Int, forComponent component: Int, reusingView view: UIView?) -> UIView {
let myView = UIView(frame: CGRect(x: 5, y: 0, width: pickerView.bounds.width - 10, height: Utilities.isDeviceiPad() ? 80.0 : 60.0))
myView.backgroundColor = UIColor.white
myView.isOpaque = false
let myLabel = UILabel(frame: CGRect(x: 5, y: 0, width: myView.bounds.width - 10, height: myView.frame.height))
myLabel.text = arrTemp[row]
// myLabel.center.y = myView.center.y
myLabel.textAlignment = .center
myLabel.numberOfLines = 2
myLabel.backgroundColor = UIColor.white
myLabel.alpha = CGFloat(1)
myLabel.lineBreakMode = NSLineBreakMode.byTruncatingTail
myView.addSubview(myLabel)
return myView
}