当打开键盘时，它100%完美地回答了所有人的更新表视图高度

对于Swift4.2

   override func viewDidLoad() {
      super.viewDidLoad()
      NotificationCenter.default.addObserver(self, selector: #selector(RecipeVC.keyboardWillShow), name: UIResponder.keyboardWillShowNotification, object: nil)

      NotificationCenter.default.addObserver(self, selector: #selector(RecipeVC.keyboardWillHide), name: UIResponder.keyboardWillHideNotification, object: nil)
   }

   @objc func keyboardWillShow(notification: NSNotification) {
    if ((notification.userInfo?[UIResponder.keyboardFrameBeginUserInfoKey] as? NSValue)?.cgRectValue) != nil {

        var userInfo = notification.userInfo!
        var keyboardFrame:CGRect = (userInfo[UIResponder.keyboardFrameEndUserInfoKey] as! NSValue).cgRectValue
        keyboardFrame = self.view.convert(keyboardFrame, from: nil)

        var contentInset:UIEdgeInsets = self.tbl.contentInset
          contentInset.bottom = keyboardFrame.size.height
          self.tbl.contentInset = contentInset
    }
}

   @objc func keyboardWillHide(notification: NSNotification) {
    if ((notification.userInfo?[UIResponder.keyboardFrameEndUserInfoKey] as? NSValue)?.cgRectValue) != nil {
        let contentInset:UIEdgeInsets = UIEdgeInsets(top: 0, left: 0, bottom: 0, right: 0)
        self.tbl.contentInset = contentInset
    }
}

Swift3.2

    override func viewDidLoad() {
          super.viewDidLoad()

           NotificationCenter.default.addObserver(self, selector: #selector(RecipeVC.keyboardWillShow), name: NSNotification.Name.UIKeyboardWillShow, object: nil)

           NotificationCenter.default.addObserver(self, selector: #selector(RecipeVC.keyboardWillHide), name: NSNotification.Name.UIKeyboardWillHide, object: nil)
    }
    func keyboardWillShow(notification: NSNotification) {
         if ((notification.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.cgRectValue) != nil {
         //self.view.frame.origin.y -= keyboardSize.height
         var userInfo = notification.userInfo!
         var keyboardFrame:CGRect = (userInfo[UIKeyboardFrameEndUserInfoKey] as! NSValue).cgRectValue
          keyboardFrame = self.view.convert(keyboardFrame, from: nil)

          var contentInset:UIEdgeInsets = self.tbl.contentInset
          contentInset.bottom = keyboardFrame.size.height
          self.tbl.contentInset = contentInset

       }
    }

    func keyboardWillHide(notification: NSNotification) {
         if ((notification.userInfo?[UIKeyboardFrameEndUserInfoKey] as? NSValue)?.cgRectValue) != nil {
         let contentInset:UIEdgeInsets = UIEdgeInsets(top: 0, left: 0, bottom: 0, right: 0)
         self.tbl.contentInset = contentInset
         }
    }

最简单的方法，甚至不需要任何代码:

下载KeyboardLayoutConstraint.swift并将文件添加(拖放)到你的项目中，如果你还没有使用Spring动画框架的话。 在你的故事板中，为视图或文本字段创建一个底部约束，选择约束(双击它)，在标识检查器中，将其类从NSLayoutConstraint更改为KeyboardLayoutConstraint。 完成了!

物体会随着键盘同步自动移动。

类似于@Boris的回答，但在Swift 5中:

override func viewDidLoad() {
    NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillShow), name: UIResponder.keyboardWillShowNotification, object: nil)
    NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillHide), name: UIResponder.keyboardWillHideNotification, object: nil)
}

@IBAction func keyboardWillShow(notification: NSNotification) {
    if let keyboardSize = (notification.userInfo?[UIResponder.keyboardFrameBeginUserInfoKey] as? NSValue)?.cgRectValue {
        if self.view.frame.origin.y == 0 {
            self.view.frame.origin.y -= keyboardSize.height
        }
    }
}

@IBAction func keyboardWillHide(notification: NSNotification) {
    if self.view.frame.origin.y != 0 {
        self.view.frame.origin.y = 0
    }
}

我改进了其中一个答案，使它与不同的键盘和不同的文本视图/字段在一个页面上工作:

添加观察员:

override func viewWillAppear(_ animated: Bool) {
    super.viewWillAppear(animated)

    NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillChange(notification:)), name: UIResponder.keyboardWillChangeFrameNotification, object: nil)

    NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillHide), name: UIResponder.keyboardWillHideNotification, object: nil)
}

func keyboardWillHide() {
    self.view.frame.origin.y = 0
}

func keyboardWillChange(notification: NSNotification) {

    if let keyboardSize = (notification.userInfo?[UIResponder.keyboardFrameEndUserInfoKey] as? NSValue)?.cgRectValue {
        if YOURTEXTVIEW.isFirstResponder {
            self.view.frame.origin.y = -keyboardSize.height
        }
    }
}

删除观察员:

override func viewWillDisappear(_ animated: Bool) {
    super.viewWillDisappear(animated)

    NotificationCenter.default.removeObserver(self, name: UIResponder.keyboardWillChangeFrameNotification, object: nil)
    NotificationCenter.default.removeObserver(self, name: UIResponder.keyboardWillHideNotification, object: nil)
}

Swift 3更新…

正如其他人所说，你需要在控制器的viewDidLoad()方法中添加通知观察者，如下所示:

NotificationCenter.default.addObserver(forName: .UIKeyboardWillShow, object: nil, queue: nil)
    { notification in
    self.keyboardWillShow(notification)
    }

NotificationCenter.default.addObserver(forName: .UIKeyboardWillHide, object: nil, queue: nil)
    { notification in
    self.keyboardWillHide(notification)
    }

NotificationCenter.default.addObserver(forName: .UIKeyboardDidShow, object: nil, queue: nil)
    { _ in
    self.enableUserInteraction()
    }

NotificationCenter.default.addObserver(forName: .UIKeyboardDidHide, object: nil, queue: nil)
    { _ in
    self.enableUserInteraction()
    }

记得在适当的地方删除你的观察器(我在viewWillDisappear()方法中这样做)

NotificationCenter.default.removeObserver(self, name: .UIKeyboardWillShow, object: nil)
NotificationCenter.default.removeObserver(self, name: .UIKeyboardWillHide, object: nil)
NotificationCenter.default.removeObserver(self, name: .UIKeyboardDidShow, object: nil)
NotificationCenter.default.removeObserver(self, name: .UIKeyboardDidHide, object: nil)

然后，实现你的show和hide方法——注意告诉应用程序忽略交互事件的行(beginIgnoringInteractionEvents)。这很重要，因为如果没有它，用户可能会点击一个字段甚至滚动视图，导致第二次发生移位，从而导致可怕的UI故障。在键盘显示和隐藏之前忽略交互事件将防止这种情况:

func keyboardWillShow(notification: Notification)
    {
    if let keyboardSize = (notification.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.cgRectValue
        {
        UIApplication.shared.beginIgnoringInteractionEvents()
        self.view.frame.origin.y -= keyboardSize.height
        // add this line if you are shifting a scrollView, as in a chat application
        self.timelineCollectionView.contentInset.top += keyboardSize.height
        }
    }

func keyboardWillHide(notification: Notification)
    {
    if let keyboardSize = (notification.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.cgRectValue
        {
        UIApplication.shared.beginIgnoringInteractionEvents()
        self.view.frame.origin.y += keyboardSize.height
        // add this line if you are shifting a scrollView, as in a chat application
        self.timelineCollectionView.contentInset.top -= keyboardSize.height
        }
    }

最后，重新启用用户交互(记住，这个方法在键盘didShow或didHide之后触发):

func enableUserInteraction()
    {
    UIApplication.shared.endIgnoringInteractionEvents()
    }

对于Swift 3，我做了一个UIViewController子类，因为我需要在所有的视图控制器中恒定的行为。

class SomeClassVC: UIViewController {

  //MARK: - Lifecycle
  override func viewDidLoad() {
    super.viewDidLoad()

    addKeyboardObservers()
  }

  override func viewWillDisappear(_ animated: Bool) {
    super.viewWillDisappear(animated)

    removeKeyboardObservers()
  }

  //MARK: - Overrides
  override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
    view.endEditing(true)
  }

  //MARK: - Help
  func addKeyboardObservers() {
    NotificationCenter.default.addObserver(self, selector: #selector(self.keyboardWillShow), name: NSNotification.Name.UIKeyboardWillShow, object: nil)
    NotificationCenter.default.addObserver(self, selector: #selector(self.keyboardWillHide), name: NSNotification.Name.UIKeyboardWillHide, object: nil)
  }

  func removeKeyboardObservers() {
    NotificationCenter.default.removeObserver(self, name: NSNotification.Name.UIKeyboardWillShow, object: self.view.window)
    NotificationCenter.default.removeObserver(self, name: NSNotification.Name.UIKeyboardWillHide, object: self.view.window)
  }

  func keyboardWillShow(notification: NSNotification) {
    let keyboardHeight = (notification.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.cgRectValue.height
    UIView.animate(withDuration: 0.1, animations: { () -> Void in
      self.view.window?.frame.origin.y = -1 * keyboardHeight!
      self.view.layoutIfNeeded()
    })
  }

  func keyboardWillHide(notification: NSNotification) {
    UIView.animate(withDuration: 0.1, animations: { () -> Void in
      self.view.window?.frame.origin.y = 0
      self.view.layoutIfNeeded()
    })
  }

  func resignTextFieldFirstResponders() {
    for textField in self.view.subviews where textField is UITextField {
      textField.resignFirstResponder()
    }
  }

  func resignAllFirstResponders() {
      view.endEditing(true)
  }
}