Custom UITabBarController - DidSelect/AnyCustomization delegate problem - ios

Question

I created custom TabBar class, but I have few problems, how I can call any function from this class when for example tab is hidden? (I would like to hide my stripe when tab bar is hidden) Also when I use tabBarController?.selectedIndex = 3 the delegate didSelect is not called, how can I solve it? That is my simple code. Thanks for any help
class customTabBar: UITabBarController {
var stripe = UIView()
override func viewDidLoad() {
super.viewDidLoad()
let cellWidth = tabBar.frame.width/5
stripe = UIView(frame: CGRect(x: 0, y: tabBar.frame.minY + 20, width: (tabBar.frame.width/5) * 0.6, height: 6))
stripe.center.x = cellWidth/2
stripe.applyGradient(colours: [UIColor.init(hexFromString: "5897ee"),UIColor.init(hexFromString: "5228d8")])
stripe.layer.cornerRadius = 2
stripe.layer.masksToBounds = true
self.view.addSubview(stripe)
}
override func tabBar(_ tabBar: UITabBar, didSelect item: UITabBarItem) {
let index: Int = item.tag + 1
let cellWidth = tabBar.frame.width/5
let newPostion = cellWidth * CGFloat(index)
UIView.animate(withDuration: 0.3, delay: 0, usingSpringWithDamping: 1, initialSpringVelocity: 0.3, options: .curveEaseInOut, animations: {
self.stripe.center.x = newPostion - (cellWidth/2)
})
}
}

Answer 1

class MyTabBarController: UITabBarController {
override func viewDidLoad() {
super.viewDidLoad()
//Add the stripe to tabBar，so it will hidden when tabBar hidden
let cellWidth = tabBar.frame.width/5
let stripe = UIView(frame: CGRect(x: 0, y: tabBar.frame.minY + 20, width: (tabBar.frame.width/5) * 0.6, height: 6))
stripe.center.x = cellWidth/2
stripe.layer.cornerRadius = 2
stripe.layer.masksToBounds = true
self.tabBar.addSubview(stripe)
}
//use this to observe tabBarController?.selectedIndex = 3
override var selectedIndex: Int{
didSet{
//do what you want
}
}
}
extension UIViewController {
//use this to call get MyTabBarController instance and call any function
var myTabBarcontroller : MyTabBarController?{
get{
return self.tabBarController as? MyTabBarController
}
}
}