Check out example codes for "swift change navigation bar color". It will help you in understanding the concepts better.

Code Example 1

// Navigation Bar:
navigationController?.navigationBar.barTintColor = UIColor.green

// Navigation Bar Text:
navigationController?.navigationBar.titleTextAttributes = [.foregroundColor: UIColor.orange]

// Tab Bar:
tabBarController?.tabBar.barTintColor = UIColor.brown

// Tab Bar Text:
tabBarController?.tabBar.tintColor = UIColor.yellow

Code Example 2

// Navigation Bar:
navigationController?.navigationBar.barTintColor = UIColor.green

// Navigation Bar Text:
navigationController?.navigationBar.titleTextAttributes = [.foregroundColor: UIColor.orange]

// Tab Bar:
tabBarController?.tabBar.barTintColor = UIColor.brown

// Tab Bar Text:
tabBarController?.tabBar.tintColor = UIColor.yellow

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