Add UIView over Navigation Bar after Push Segue

Question

I have two ViewControllers . I want to add an UIView over the navigation bar.

I could add the UIView on top of the first navigation bar by creating an UINavigationItem Outlet and adding the UIView created programatically to the UINavigationItem outlet titleView .

Code Snippet (HomeVC - Fist ViewController):

class HomeVC: UIViewController {

@IBOutlet weak var homeNavigationItem: UINavigationItem!
let navBarView = UIView()
let topNavBarLabel = UILabel()
let screenWidth = UIScreen.main.bounds.width

override func viewDidLoad() {
    super.viewDidLoad()
    // Do any additional setup after loading the view, typically from a nib.

navBarView.frame = CGRect(x: 0.0, y: 0.0, width: screenWidth, height: 50.0)

topNavBarLabel.text = "Hello World"
topNavBarLabel.textAlignment = NSTextAlignment.center
topNavBarLabel.textColor = UIColor.white
topNavBarLabel.frame = CGRect(x: 0.0, y: 10.0, width: screenWidth, height: 20.0)
navBarView.addSubview(topNavBarLabel)

homeNavigationItem.titleView = navBarView

}

override func didReceiveMemoryWarning() {
    super.didReceiveMemoryWarning()
    // Dispose of any resources that can be recreated.
}
}

Screenshot Home View:

Now incase of the SecondVC I am trying to do the same thing after the Push Segue.

Code Snippet (DetailVC - Second ViewController):

class DetailsVC: UIViewController {

let navBarView = UIView()
let screenWidth = UIScreen.main.bounds.width
let navBarTopLabel = UILabel()

override func viewDidLoad() {
    super.viewDidLoad()

    // Do any additional setup after loading the view.

navBarView.frame = CGRect(x: 0.0, y: 50.0, width: screenWidth, height: 50.0)
navBarView.backgroundColor = UIColor.black

navBarTopLabel.frame = CGRect(x: 0.0, y: 10.0, width: screenWidth, height: 20.0)
navBarTopLabel.textColor = UIColor.white
navBarTopLabel.text = "Details Hello"
navBarTopLabel.textAlignment = NSTextAlignment.center

navBarView.addSubview(navBarTopLabel)

self.view.addSubview(navBarView)
self.view.bringSubview(toFront: navBarView)
}

override func didReceiveMemoryWarning() {
    super.didReceiveMemoryWarning()
    // Dispose of any resources that can be recreated.
}
}

Screenshot Details View:

Storyboard Screenshot:

View Hierarchy:

Note: I deliberately assigned an Y-position to the view more than 0, to be sure that the view is being created

But as I am not able to create an UINavigationItem , I am adding the programmatically created view to the view and even trying to bring the subView to the front.

Note: Yes, the size of the UINavigationBar has been increased, please refer here: Change width/height UINavigationBar embedded in a Navigation Controller

Answer 1

You could use the variable defined for UIViewController

public var navigationItem: UINavigationItem { get }

From the docs:

Created on-demand so that a view controller may customize its navigation appearance.

So in each subclass of UIViewController in viewDidLoad you can just do

self.navigationItem.titleView = navBarView