Picker view overwrites the value of blur effect in swift 4.2 - ios

Question

I want to increase or decrease the level of blur effect in the photo using the pickerview. Even if I decrease the value, it adds a continuous blur effect to it. What should I do?
Working on latest Swift and Xcode
class ViewController: UIViewController,UIPickerViewDelegate,UIPickerViewDataSource {
#IBOutlet var bg: UIImageView!
#IBOutlet var pickView: UIPickerView!
func numberOfComponents(in pickerView: UIPickerView) -> Int {
return 1
}
func pickerView(_ pickerView: UIPickerView, numberOfRowsInComponent component: Int) -> Int {
return arr.count
}
func pickerView(_ pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) {
switch arr[row] {
case "1":
Blur(blur: 0.3)
case "2":
Blur(blur: 0.6)
case "3":
Blur(blur: 0.0)
default:
print("not change")
}
}
func pickerView(_ pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String? {
return arr[row]
}
let arr = ["1","2","3"]
override func viewDidLoad() {
super.viewDidLoad()
pickView.dataSource = self
pickView.delegate = self
// Do any additional setup after loading the view, typically from a nib.
}
func Blur(blur:CGFloat)
{
let blurEffect = UIBlurEffect(style: UIBlurEffect.Style.light)
let blurView = UIVisualEffectView(effect: blurEffect)
blurView.frame = bg.bounds
blurView.alpha = blur
self.view.addSubview(blurView)
}
}

Answer 1

Your Blur(blur: 0.3) is a function not an object class, it will run not change properties. And your func added a Subview to your parent View but none code line to remove it before add another. So it will be stack up.
Remove old blur subView then add new.
Create a default blur view first then change it properties.