我总是把这个添加到我的 ViewController

I always add this to my ViewController

override func viewDidLoad()
{
    super.viewDidLoad()

    // other stuff

    // but to stop editing when the user taps anywhere on the view, add this gesture recogniser
    let tapGestureBackground = UITapGestureRecognizer(target: self, action: #selector(self.backgroundTapped(_:)))
    self.view.addGestureRecognizer(tapGestureBackground)
}

func backgroundTapped(_ sender: UITapGestureRecognizer)
{
    self.endEditing(true)   
}