ViewControllerに検索機能追加

class ViewController: UIViewController {
    let searchController = UISearchController()

    override func viewDidLoad() {
        super.viewDidLoad()

        searchController.searchResultsUpdater = self
        navigationItem.searchController = searchController
    }
}

extension ViewController: UISearchResultsUpdating {
    func updateSearchResults(for searchController: UISearchController) {
        guard let text = searchController.searchBar.text else { return }
        // search the result base on text
    }
}