Navigation bar appear from black color? - ios

Question

I am setting a new navigation for my app on launch. But when I launch it appears from a black color animation.After black color it sets it navigation bar. Please tell me what is issue.
I am using below code
var controller = UIViewController()
//App Theming
var navController = UINavigationController()
navController.navigationBar.barTintColor = UIColor.white
navController.navigationBar.tintColor = UIColor.white
navController.navigationBar.titleTextAttributes = [NSAttributedStringKey.foregroundColor: UIColor.white]
navController.navigationBar.shadowImage = UIImage()
navController.navigationBar.setBackgroundImage(UIImage(), for: .default)
navController.navigationBar.isTranslucent = false
navController = UINavigationController(rootViewController: viewcontroller)
navController.navigationBar.isHidden = true
let appDelegate = UIApplication.shared.delegate as! AppDelegate
appDelegate.window?.rootViewController = navController
appDelegate.window?.makeKeyAndVisible()

Answer 1

The problem is this line:
navController.navigationBar.isHidden = true
Delete it and try again.

Answer 2

Please use snippet bellow
In this I am using ViewController from Main storyboard
// mainStoryboard
let mainStoryboard = UIStoryboard(name: "Main", bundle: nil)
// rootViewController
let rootViewController = mainStoryboard.instantiateViewController(withIdentifier: "ViewController") as? ViewController
// navigationController
let navigationController = UINavigationController(rootViewController: rootViewController!)
//App Theming
navigationController.navigationBar.barTintColor = UIColor.white
navigationController.navigationBar.tintColor = UIColor.white
navigationController.navigationBar.titleTextAttributes = [NSAttributedStringKey.foregroundColor: UIColor.white]
navigationController.title = "Testing Th"
navigationController.navigationBar.shadowImage = UIImage()
navigationController.navigationBar.setBackgroundImage(UIImage(), for: .default)
navigationController.navigationBar.isTranslucent = false
navigationController.navigationBar.isHidden = true
// self.window
self.window = UIWindow(frame: UIScreen.main.bounds)
self.window!.rootViewController = navigationController
self.window!.makeKeyAndVisible()
If I unhide NavigationBar
navigationController.navigationBar.isHidden = false
you can clearly see the results

Answer 3

I can see that you did not give the navigationController any viewControllers.
You need to pass the navigation controller at least one viewController for it to know which viewController to start your
navigation process from, follow the code below:
var window: UIWindow?
let nav = UINavigationController()
1- here is where i declared my Initial viewController (where i want my navigation process to start from)
var main = HomeViewController(nibName: "HomeViewController", bundle: nil)
2- here is where i give the navigationController the first viewController to start from.
window?.rootViewController = nav
nav.viewControllers = [main]//you need to have this line
nav.isNavigationBarHidden = true
window?.makeKeyAndVisible()

Answer 4

alright i just noticed you're using storyboards, give this a try:
var storyboard = UIStoryboard(name: "Main", bundle: nil)
var ivc = storyboard.instantiateViewController(withIdentifier: "ViewController") as? ViewController
navigationController?.pushViewController(anIvc, animated: true)
window.rootViewController = ivc
window.rootViewController = navigationController
window.makeKeyAndVisible()

Answer 5

Your code should be placed in
import UIKit
// AppDelegate class file
func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplicationLaunchOptionsKey: Any]?) -> Bool {
// Be attentive. controller allocated withou any layout. Change to custom controller class or load from IB resource (storyboard/nib)
let controller = UIViewController()
let navigationController = rootNavigationController
// Setup viewControllers. Just one controller as root
navigationController.viewControllers = [controller]
// You already have a reference to window in your AppDelegate
window.rootViewController = navigationController
window.makeKeyAndVisible()
}
extension AppDelegate {
// Move out of AppDelegate class code to create theming NavigationController
private var rootNavigationController: UINavigationController {
let navController = UINavigationController()
navController.navigationBar.barTintColor = UIColor.white
navController.navigationBar.tintColor = UIColor.white
navController.navigationBar.titleTextAttributes = [NSAttributedStringKey.foregroundColor: UIColor.white]
navController.navigationBar.shadowImage = UIImage()
navController.navigationBar.setBackgroundImage(UIImage(), for: .default)
navController.navigationBar.isTranslucent = false
navController.navigationBar.isHidden = true
// If it theme for all application you should use appearances
/* For Example
UINavigationBar.appearance().titleTextAttributes = [NSAttributedStringKey.foregroundColor: UIColor.white]
UINavigationBar.appearance().tintColor = .white
*/
return navController
}
}
You possible errors:
controller instance haven't any layout. By default ViewController
haven't anything
You code call from separated place. It's market by you call of AppDelegate instance. Configure you rootViewController in
didFinishLoading
You have an separated ViewController that placed as root