Could not cast value of type 'UINavigationController'

Question

I am implementing a search interface for my application, so basically I will pass the search keyword from one ViewController to another ViewController.

I have done this

Answer 1

Based on Semih's answer, you can also do this to pass a variable to next segue if you don't want to use an identifier:

override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
    if let nav = segue.destination as? UINavigationController, 
        let vc = nav.topViewController as? TestViewController {
        vc.username = "Test"
    }
}