import UIKit

class DetailViewController: UIViewController {
   override func viewDidLoad() {
      super.viewDidLoad()
      let label = UILabel()
      label.frame = CGRect(x: 20, y: 16, width: 250, height: 30)
      label.font = UIFont.systemFont(ofSize: 30)
      label.text = "Hello World!"
      view.addSubview(label)
   }
}