Pass data using TabBarController - swift

Question

I know this question has been ask a lot on stack overflow. So I have a TabBarController that has 2 NavigationController, which both NavigationController have a TableViewController. I am using firebase to get a user, saving the user into a variable called currentUser. Now my problem starts here, I want to set the 2nd Navigation/Tableview controller title to the user's name. I know how to pass data using the prepare for segue, however there is no segue in TabBarController.
I've found a solution, not sure if its good or bad. What I did was make the first controller to be the delegate of the tab bar. Then I added tabBarController did select method. Here is the code.
class FirstTableVC: UITableViewController, UITabBarControllerDelegate {
var currentUser: User?
override func viewDidLoad() {
super.viewDidLoad()
tabBarController?.delegate = self
}
//Code that saves user
func code() {
...
...
...
}
func tabBarController(_ tabBarController: UITabBarController, didSelect viewController: UIViewController) {
if viewController == tabBarController.viewControllers![1] {
let navController = tabBarController.viewControllers![1] as? UINavigationController
let secondTableVC = navController?.topViewController as! SecondTableVC
secondTableVC.currentUser = currentUser
}
}
}
class SecondTableVC: UITableViewController {
var currentUser: User?
override func viewDidLoad() {
super.viewDidLoad()
navigationItem.title =currentUser?.name
}
}
This works but not sure if this is a good way to do. I was wondering if there is a better way or a more efficient way. Thanks :)
Added:
Okay read this article about passing data using tabController. The author says that we should pass data using the state of the app. I am not really sure what he means by this. This is what I though he meant.
Example code:
class Person {
var name: String
var email: String
static var currentPerson: Person?
init(name: String, email: String) {
self.name = name
self.email = email
}
}
Can some please help me clarify . Thanks.

Answer 1

There's nothing wrong with this solution. Another way would be to have an abstracted class responsible for the user login object (instead of FirstTableVC having responsibility) that is accessible from both FirstTableVC and SecondTableVC

Answer 2

Add this in your FirstTableVC
func code() {
...
...
...
self.changeTabbarTitle()
}
func changeTabbarTitle() {
if let items = self.tabBarController?.tabBar.items {
items[1].title = currentUser?.name
}
}

Answer 3

You can use with delegate protocol
create NavigationTitle Protocol in FirstViewController
protocol NavigationTitle{
func setTitle(name:String)
}
class FirstViewController: UITableViewController,UITabBarControllerDelegate{
var delegate: NavigationTitle?
func setCurrentUser(){
delegate.setTitle(name:self.currentUser?.name)
}
func tabBarController(_ tabBarController: UITabBarController, didSelect viewController: UIViewController) {
if viewController == tabBarController.viewControllers![1] {
let navController = tabBarController.viewControllers![1] as? UINavigationController
let secondTableVC = navController?.topViewController as! SecondTableVC
self.delegate = secondTableVC.self
}
}
}
implement protocol in SecondVC
class SecondVC: UITableViewController,NavigationTitle{
func setTitle(name:String){
navigationItem.title = name
}
}