在不使用alpha的情况下使用UISegmentedControl在视图ios之间切换？

let parentView = UIView(frame: CGRect(x: 0, y: 0, width: UIScreen.main.bounds.width, height: UIScreen.main.bounds.height))
self.view.addSubview(parentView)

let segmentedControl = UISegmentedControl(items: ["View 1", "View 2", "View 3"])
segmentedControl.frame = CGRect(x: 20, y: 20, width: UIScreen.main.bounds.width - 40, height: 40)
segmentedControl.selectedSegmentIndex = 0
parentView.addSubview(segmentedControl)

let view1 = UIView(frame: CGRect(x: 0, y: 60, width: UIScreen.main.bounds.width, height: UIScreen.main.bounds.height - 60))
let view2 = UIView(frame: CGRect(x: 0, y: 60, width: UIScreen.main.bounds.width, height: UIScreen.main.bounds.height - 60))
let view3 = UIView(frame: CGRect(x: 0, y: 60, width: UIScreen.main.bounds.width, height: UIScreen.main.bounds.height - 60))

parentView.addSubview(view1)
parentView.addSubview(view2)
parentView.addSubview(view3)

view1.isHidden = false
view2.isHidden = true
view3.isHidden = true

segmentedControl.addTarget(self, action: #selector(segmentedControlValueChanged(_:)), for: .valueChanged)

@objc func segmentedControlValueChanged(_ sender: UISegmentedControl) {
    view1.isHidden = sender.selectedSegmentIndex != 0
    view2.isHidden = sender.selectedSegmentIndex != 1
    view3.isHidden = sender.selectedSegmentIndex != 2
}