对于Swift3

在viewDidLoad中注册一个事件识别器

let tap = UITapGestureRecognizer(target: self, action: #selector(hideKeyBoard))

然后我们需要在相同的viewDidLoad中添加手势到视图中。

self.view.addGestureRecognizer(tap)

然后我们需要初始化注册的方法

func hideKeyBoard(sender: UITapGestureRecognizer? = nil){
    view.endEditing(true)
}

//Simple exercise to demonstrate, assuming the view controller has a //Textfield, Button and a Label. And that the label should display the //userinputs when button clicked. And if you want the keyboard to disappear //when clicken anywhere on the screen + upon clicking Return key in the //keyboard. Dont forget to add "UITextFieldDelegate" and 
//"self.userInput.delegate = self" as below

import UIKit

class ViewController: UIViewController,UITextFieldDelegate {

    @IBOutlet weak var userInput: UITextField!
    @IBAction func transferBtn(sender: AnyObject) {
                display.text = userInput.text

    }
    @IBOutlet weak var display: UILabel!

    override func viewDidLoad() {
        super.viewDidLoad()

//This is important for the textFieldShouldReturn function, conforming to textfieldDelegate and setting it to self
        self.userInput.delegate = self
    }

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

//This is for the keyboard to GO AWAYY !! when user clicks anywhere on the view
    override func touchesBegan(touches: Set<UITouch>, withEvent event: UIEvent?) {
        self.view.endEditing(true)
    }


//This is for the keyboard to GO AWAYY !! when user clicks "Return" key  on the keyboard

    func textFieldShouldReturn(textField: UITextField) -> Bool {
        textField.resignFirstResponder()
        return true
    }

}

Dash的回答是正确的。一个更“焦土”的方法是调用view. enditing (true)。这将导致视图及其所有子视图resignFirstResponder。如果您没有想要删除的视图的引用，这是一种俗气但有效的解决方案。

请注意，我个人认为你应该有一个引用的视图，你想要有辞职第一响应者. enditing (force: Bool)是一个野蛮的方法;请不要使用它。

  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)
  }
}

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。

因为我编辑的@King-Wizard的回答被拒绝了，所以发布了一个新的答案。

让你的类成为UITextField的委托并重写touchesBegan。

斯威夫特4

import UIKit

class ViewController: UIViewController, UITextFieldDelegate {

    @IBOutlet var textField: UITextField!

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

    //Called when 'return' key is pressed. Return false to keep the keyboard visible.
    func textFieldShouldReturn(textField: UITextField) -> Bool {
        return true
    }

    // Called when the user clicks on the view (outside of UITextField).
    override func touchesBegan(touches: Set<UITouch>, with event: UIEvent?) {
        self.view.endEditing(true)
    }

}