UISearchBar custom corners

I am using this code UISearchBar but you can use this code with UISearchController.

    let searchBar = UISearchBar()
                searchBar.sizeToFit()
                searchBar.placeholder = "Search"
                navigationItem.titleView = searchBar

                if let textfield = searchBar.value(forKey: "searchField") as? UITextField {
                    textfield.textColor = UIColor.blue
                    if let backgroundview = textfield.subviews.first {
                        // Background color
                        backgroundview.backgroundColor = UIColor.white
                        // Rounded corner
                        backgroundview.layer.cornerRadius = 14;
                        backgroundview.clipsToBounds = true;
                    }
                }

You should change the radius of searchTextField inside UISearchBar .

you can do that like this :

searchBar.searchTextField.layer.cornerRadius = 20
searchBar.searchTextField.layer.masksToBounds = true

* searchBar is an outlet of UISearchBar from storyBoard