导航 Controller 在使用 TabBar 控制器时不显示标题（以编程方式）

Question

I'm using a navigationController as the window.rootViewController . And as the rootViewController of navigationController , I'm using a tabBarController. But when I run the app, the title of the navigationBar is not showing up (My Tabbar Controller shows up and I'm being able to see my viewController. No problem about that) . I've tried to name the navigationBar in every viewController of the tabBar with using both of the code below in the viewDidload, but still nothing changed.

 navigationController?.title = "title"
 navigationController?.navigationBar.topItem?.title = "title"

I've set the navigationController with tabbar in the SceneDelegete as below:

let countriesTabbarController = TabBarControllerBuilder.build()
    
    let navigationController = UINavigationController(rootViewController: countriesTabbarController)
    
    window?.rootViewController = navigationController
    window?.makeKeyAndVisible()

How can I show my navigationController title for every viewController of the tabBar?

Answer 1

Each view controller has a property called navigationItem of type UINavigationItem . If you set its title , it will show up in the navigation bar if one exists.

For example in viewDidLoad , add this:

self.navigationItem.title = "title"

In other words: The title is set on the view controller contained in a navigation controller stack, not the navigation controller itself. Also not on the navigation bar, which probably also has a good reason I can't recall at the moment.

https://developer.apple.com/documentation/uikit/uinavigationitem