Labels on navigationbar in swift - ios

Question

I have three views in navigationBar.
I want to place labels on navigation bar so that when i will go to one view to another it will show the page number . Here is my code. I have written this code in The viewDidLoad of all the three class
if let navigationBar = self.navigationController?.navigationBar {
let firstFrame = CGRect(x: navigationBar.frame.width/2, y: 8, width: 15, height: 10)
let secondFrame = CGRect(x: navigationBar.frame.width/2 + 30, y: 8, width: 15, height: 10)
let thirdFrame = CGRect(x: navigationBar.frame.width/2 + 60, y: 8, width: 15, height: 10)
let firstLabel = UILabel(frame: firstFrame)
firstLabel.text = "1"
let secondLabel = UILabel(frame: secondFrame)
secondLabel.text = "of"
let thirdLabel = UILabel(frame: thirdFrame)
secondLabel.text = "3"
navigationBar.addSubview(firstLabel)
navigationBar.addSubview(secondLabel)
navigationBar.addSubview(thirdLabel)
}
But the problem is the same label repeating in every view controller.It is showing like "1 of 3" in every view controller *

Answer 1

First create subclass of UINavigationController
class NavigationController: UINavigationController {
}
don't forget to change class of your UINavigationController in Storyboard
now in your UINavigationController subclass create properties of your labels and set them
class NavigationController: UINavigationController {
var firstLabel: UILabel?
var secondLabel: UILabel?
var thirdLabel: UILabel?
override func viewDidLoad() {
super.viewDidLoad()
firstLabel = UILabel(frame: CGRect(x: navigationBar.frame.width/2, y: 8, width: 15, height: 10))
secondLabel = UILabel(frame: CGRect(x: navigationBar.frame.width/2 + 30, y: 8, width: 15, height: 10))
thirdLabel = UILabel(frame: CGRect(x: navigationBar.frame.width/2 + 60, y: 8, width: 15, height: 10))
navigationBar.addSubview(firstLabel)
navigationBar.addSubview(secondLabel)
navigationBar.addSubview(thirdLabel)
firstLabel.text = "1"
secondLabel.text = "of"
thirdLabel.text = "3"
}
}
then you want to change firstLabel.text every time you move to another ViewController. So, in ViewController in viewWillAppear get reference for your NavigationController and set text of this firstLabel like this
class ViewController1: UIViewController {
override func viewWillAppear(_ animated: Bool) {
if let navController = navigationController as? NavigationController {
navController.firstLabel?.text = "1"
}
}
}
and then do the same for second and third UIViewController
class ViewController2: UIViewController {
override func viewWillAppear(_ animated: Bool) {
if let navController = navigationController as? NavigationController {
navController.firstLabel?.text = "2"
}
}
}
...