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

Code Example 1

// Place this in your didFinishLaunchingWithOptions method in the AppDelegate
let attrs = [
  NSAttributedString.Key.foregroundColor: UIColor.white, // changes color
  NSAttributedString.Key.font: UIFont(name: "Futura-Bold", size: 17)! // changes font
]

UINavigationBar.appearance().titleTextAttributes = attrs

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