import UIKit

  class ItemViewController: UIViewController, UITextFieldDelegate {

  @IBOutlet weak var nameTextField: UITextField!

    override func viewDidLoad() {
           super.viewDidLoad()
           self.nameTextField.delegate = self
     }

    // Called when 'return' key pressed. return NO to ignore.

    func textFieldShouldReturn(textField: UITextField) -> Bool {

            textField.resignFirstResponder()
             return true
     }

 // Called when the user click on the view (outside the UITextField).

override func touchesBegan(touches: Set<UITouch>, withEvent event: UIEvent?)    {
      self.view.endEditing(true)
  }
}

斯威夫特3: 关闭键盘的最简单方法:

  //Dismiss keyboard method
    func keyboardDismiss() {
        textField.resignFirstResponder()
    }

    //ADD Gesture Recignizer to Dismiss keyboard then view tapped
    @IBAction func viewTapped(_ sender: AnyObject) {
        keyboardDismiss()
    }

    //Dismiss keyboard using Return Key (Done) Button
    //Do not forgot to add protocol UITextFieldDelegate 
    func textFieldShouldReturn(_ textField: UITextField) -> Bool {
        keyboardDismiss()

        return true
    }

我没有看到它被提到过，但是NotificationCenter可以告诉你键盘何时打开和关闭。例如，如果你想改变cancelsTouchesInView或一起删除手势识别器，这可以被使用。

例子:

var dismissKeyboardGestureRecognizer = UITapGestureRecognizer()

override func viewDidLoad() {
    super.viewDidLoad()

    //Setup dismiss keyboard gesture
    self.dismissKeyboardGestureRecognizer = UITapGestureRecognizer(target: self, action: #selector(dismissKeyboard))

    //Add Notifications
    NotificationCenter.default.addObserver(self, selector: #selector(keyboardDidShow), name:UIResponder.keyboardDidShowNotification, object: nil)
    NotificationCenter.default.addObserver(self, selector: #selector(keyboardDidHide), name:UIResponder.keyboardDidHideNotification, object: nil)
}

@objc func keyboardDidShow() {
    dismissKeyboardGestureRecognizer.cancelsTouchesInView = true
    view.addGestureRecognizer(dismissKeyboardGestureRecognizer)
}

@objc func keyboardDidHide() {
    dismissKeyboardGestureRecognizer.cancelsTouchesInView = false
    view.removeGestureRecognizer(dismissKeyboardGestureRecognizer)
}

@objc func dismissKeyboard() {
    view.endEditing(true)
}

使用IQKeyboardmanager，将帮助您解决简单.....

/////////////////////////////////////////

[如何禁用键盘..][1].

import UIKit

class ViewController: UIViewController,UITextFieldDelegate {

   @IBOutlet weak var username: UITextField!
   @IBOutlet weak var password: UITextField!

   override func viewDidLoad() {
      super.viewDidLoad() 
      username.delegate = self
      password.delegate = self
      // Do any additional setup after loading the view, typically from a nib.
   }

   override func didReceiveMemoryWarning() {
      super.didReceiveMemoryWarning()
      // Dispose of any resources that can be recreated.
   }

   func textFieldShouldReturn(textField: UITextField!) -> Bool // called when   'return' key pressed. return NO to ignore.
   {
      textField.resignFirstResponder()
      return true;
   }

   override func touchesBegan(_: Set<UITouch>, with: UIEvent?) {
     username.resignFirstResponder()
     password.resignFirstResponder()
     self.view.endEditing(true)
  }
}

我找到了一个简单的解决办法: 1. 添加UITapGestureRecognizer到你的视图控制器 2. 添加IBAction到你的UITapGestureRecognizer 3.最后，您可以放弃第一个响应器

class ViewController: UIViewController
{

@IBOutlet var tap: UITapGestureRecognizer!
@IBOutlet weak var label: UILabel!
@IBOutlet weak var textField: UITextField!
override func viewDidLoad()
{
    super.viewDidLoad()
    // Do any additional setup after loading the view, typically from a nib.
}


@IBAction func dismissUsingGesture(_ sender: UITapGestureRecognizer)
{
   self.textField.resignFirstResponder()
    label.text = textField.text!
}
}

你可以打电话

resignFirstResponder()

在UIResponder的任何实例上，例如UITextField。如果你在当前导致键盘显示的视图上调用它，那么键盘将会消失。