UITabbarController replace the last view controller - ios

Question

I need replace the last view controller, depending on the condition. Into TabBarController I have 4 view controllers, last view controller it's LoginVC. If I'm already logged in I need replace LoginVC to ProfileVC.
I try:
func tabBarController(_ tabBarController: UITabBarController, shouldSelect viewController: UIViewController) -> Bool {
if tabBarController.selectedIndex == 3 && !DefaultsManager.instance.getUserToken().isEmpty {
showProfile()
return false
}
return true
}
func tabBarController(_ tabBarController: UITabBarController, didSelect viewController: UIViewController) {
if tabBarController.selectedIndex == 3 && !DefaultsManager.instance.getUserToken().isEmpty {
showProfile()
}
}
func showProfile() {
let profile = ProfileVC.instantiateNCFromStoryboard()
self.viewControllers?[3] = profile
}
But it's does't work for me.
screen with login screen
screen profile screen with my condition

Answer 1

In AppDelegate check user login status and change the last view controller and its tabBarItem
func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {
if let rootVC = self.window?.rootViewController as? UITabBarController, var viewControllers = rootVC.viewControllers {
viewControllers.removeLast()
if userLoggedIn {
let profileVC = ProfileVC()
//profileVC.tabBarItem = UITabBarItem(title: nil, image: UIImage(named: "imgName"), selectedImage: UIImage(named: "imgName"))
profileVC.tabBarItem = UITabBarItem(title: "Profile", image: nil, selectedImage: nil)
viewControllers.append(profileVC)
} else {
let loginVC = LoginVC()
//loginVC.tabBarItem = UITabBarItem(title: nil, image: UIImage(named: "imgName"), selectedImage: UIImage(named: "imgName"))
loginVC.tabBarItem = UITabBarItem(title: "Login", image: nil, selectedImage: nil)
viewControllers.append(loginVC)
}
rootVC.viewControllers = viewControllers
}
return true
}
In LoginVC upon successfull login, remove LoginVC from tabBarController and add ProfileVC
#objc func loginBtnAction(_ sender: UIButton) {
if var viewControllers = self.tabBarController?.viewControllers {
viewControllers.removeLast()
let profileVC = ProfileVC()
//profileVC.tabBarItem = UITabBarItem(title: nil, image: UIImage(named: "imgName"), selectedImage: UIImage(named: "imgName"))
profileVC.tabBarItem = UITabBarItem(title: "Profile", image: nil, selectedImage: nil)
viewControllers.append(profileVC)
self.tabBarController?.viewControllers = viewControllers
}
}
In Logout button action from ProfileVC, remove ProfileVC from tabBarController and add LoginVC
#objc func logoutBtnAction(_ sender: UIButton) {
if var viewControllers = self.tabBarController?.viewControllers {
viewControllers.removeLast()
let loginVC = LoginVC()
//loginVC.tabBarItem = UITabBarItem(title: nil, image: UIImage(named: "imgName"), selectedImage: UIImage(named: "imgName"))
loginVC.tabBarItem = UITabBarItem(title: "Login", image: nil, selectedImage: nil)
viewControllers.append(loginVC)
self.tabBarController?.viewControllers = viewControllers
}
}