Swift 5解决方案frédéric-adda:

protocol KeyboardHandler: class {
    var bottomConstraint: NSLayoutConstraint! { get set }
    
    func keyboardWillShow(_ notification: Notification)
    func keyboardWillHide(_ notification: Notification)
    func startObservingKeyboardChanges()
    func stopObservingKeyboardChanges()
}


extension KeyboardHandler where Self: UIViewController {

    func startObservingKeyboardChanges() {

        // NotificationCenter observers
        NotificationCenter.default.addObserver(forName: UIResponder.keyboardWillShowNotification, object: nil, queue: nil) { [weak self] notification in
          self?.keyboardWillShow(notification)
        }

        // Deal with rotations
        NotificationCenter.default.addObserver(forName: UIResponder.keyboardWillChangeFrameNotification, object: nil, queue: nil) { [weak self] notification in
          self?.keyboardWillShow(notification)
        }

        // Deal with keyboard change (emoji, numerical, etc.)
        NotificationCenter.default.addObserver(forName: UITextInputMode.currentInputModeDidChangeNotification, object: nil, queue: nil) { [weak self] notification in
          self?.keyboardWillShow(notification)
        }

        NotificationCenter.default.addObserver(forName: UIResponder.keyboardWillHideNotification, object: nil, queue: nil) { [weak self] notification in
          self?.keyboardWillHide(notification)
        }
    }


    func keyboardWillShow(_ notification: Notification) {

      let verticalPadding: CGFloat = 20 // Padding between the bottom of the view and the top of the keyboard

        guard let value = notification.userInfo?[UIResponder.keyboardFrameEndUserInfoKey] as? NSValue else { return }
      let keyboardHeight = value.cgRectValue.height

      // Here you could have more complex rules, like checking if the textField currently selected is actually covered by the keyboard, but that's out of this scope.
      self.bottomConstraint.constant = keyboardHeight + verticalPadding

      UIView.animate(withDuration: 0.1, animations: { () -> Void in
          self.view.layoutIfNeeded()
      })
  }


  func keyboardWillHide(_ notification: Notification) {
      self.bottomConstraint.constant = 0

      UIView.animate(withDuration: 0.1, animations: { () -> Void in
          self.view.layoutIfNeeded()
      })
  }


  func stopObservingKeyboardChanges() {
      NotificationCenter.default.removeObserver(self)
  }
}

在任何UIViewController中:

遵循KeyboardHandler协议

extension AnyViewController: KeyboardHandler {} 

为屏幕上最后一个底部元素添加底部约束。

@IBOutlet var bottomConstraint: NSLayoutConstraint! 

添加观察者订阅/取消订阅:

 override func viewWillAppear(_ animated: Bool) {
        super.viewWillAppear(animated)
        startObservingKeyboardChanges()
 }
    
 override func viewWillDisappear(_ animated: Bool) {
        super.viewWillDisappear(animated)
        stopObservingKeyboardChanges()
 }

享受吧!

我喜欢简洁的Swift代码。这是我能想出的最严格的代码，可以用键盘上下移动文本视图。它目前正在iOS8/9 Swift 2生产应用程序中运行。

更新(2016年3月): 我只是尽可能地压缩了之前的代码。此外，这里还有一些流行的答案，它们硬编码了键盘高度和动画参数。这是没有必要的，更不用说这些答案中的数字并不总是与我在6s+ iOS9上看到的实际值一致(键盘高度226，持续时间0.25，动画曲线7)。在任何情况下，几乎不需要额外的代码来直接从系统获取这些值。见下文。

override func viewDidLoad() {
    super.viewDidLoad()

    NSNotificationCenter.defaultCenter().addObserver(self, selector: "animateWithKeyboard:", name: UIKeyboardWillShowNotification, object: nil)
    NSNotificationCenter.defaultCenter().addObserver(self, selector: "animateWithKeyboard:", name: UIKeyboardWillHideNotification, object: nil)
}

func animateWithKeyboard(notification: NSNotification) {

    // Based on both Apple's docs and personal experience, 
    // I assume userInfo and its documented keys are available.
    // If you'd like, you can remove the forced unwrapping and add your own default values.

    let userInfo = notification.userInfo!
    let keyboardHeight = (userInfo[UIKeyboardFrameEndUserInfoKey] as! NSValue).CGRectValue().height
    let duration = userInfo[UIKeyboardAnimationDurationUserInfoKey] as! Double
    let curve = userInfo[UIKeyboardAnimationCurveUserInfoKey] as! UInt
    let moveUp = (notification.name == UIKeyboardWillShowNotification)

    // baseContraint is your Auto Layout constraint that pins the
    // text view to the bottom of the superview.

    baseConstraint.constant = moveUp ? -keyboardHeight : 0

    let options = UIViewAnimationOptions(rawValue: curve << 16)
    UIView.animateWithDuration(duration, delay: 0, options: options,
        animations: {
            self.view.layoutIfNeeded()
        },
        completion: nil
    )

}

注意:这段代码涵盖了大多数注释/一般情况。然而，处理不同的方向和/或自定义键盘可能需要更多的代码。如果你需要处理每一个场景，这可能会有所帮助。

在现有的答案上有一些改进。

首先，uikeyboardwillchangeframeotification可能是最好的通知，因为它处理的变化不仅仅是显示/隐藏，而是由于键盘变化(语言，使用第三方键盘等)和旋转(但注意下面的评论表明键盘将隐藏也应该处理以支持硬件键盘连接)。

其次，动画参数可以从通知中提取，以确保动画正确地组合在一起。

可能有一些选项可以进一步清理此代码，特别是如果您对强制展开字典代码感到满意的话。

 class MyViewController: UIViewController {

   // This constraint ties an element at zero points from the bottom layout guide
   @IBOutlet var keyboardHeightLayoutConstraint: NSLayoutConstraint?
 
   override func viewDidLoad() {
     super.viewDidLoad()
     NotificationCenter.default.addObserver(self,
       selector: #selector(self.keyboardNotification(notification:)),
       name: UIResponder.keyboardWillChangeFrameNotification,
       object: nil)
   }
 
   deinit {
     NotificationCenter.default.removeObserver(self)
   }
 
   @objc func keyboardNotification(notification: NSNotification) {
     guard let userInfo = notification.userInfo else { return }

     let endFrame = (userInfo[UIResponder.keyboardFrameEndUserInfoKey] as? NSValue)?.cgRectValue
     let endFrameY = endFrame?.origin.y ?? 0
     let duration:TimeInterval = (userInfo[UIResponder.keyboardAnimationDurationUserInfoKey] as? NSNumber)?.doubleValue ?? 0
     let animationCurveRawNSN = userInfo[UIResponder.keyboardAnimationCurveUserInfoKey] as? NSNumber
     let animationCurveRaw = animationCurveRawNSN?.uintValue ?? UIView.AnimationOptions.curveEaseInOut.rawValue
     let animationCurve:UIView.AnimationOptions = UIView.AnimationOptions(rawValue: animationCurveRaw)

     if endFrameY >= UIScreen.main.bounds.size.height {
       self.keyboardHeightLayoutConstraint?.constant = 0.0
     } else {
       self.keyboardHeightLayoutConstraint?.constant = endFrame?.size.height ?? 0.0
     }

     UIView.animate(
       withDuration: duration,
       delay: TimeInterval(0),
       options: animationCurve,
       animations: { self.view.layoutIfNeeded() },
       completion: nil)
   }
}

斯威夫特4。x答案，合并来自@Joseph Lord和@Isuru的答案。bottomConstraint表示你想移动的视图的底部约束。

override func viewDidLoad() {
    // Call super
    super.viewDidLoad()

    // Subscribe to keyboard notifications
    NotificationCenter.default.addObserver(self,
                                           selector: #selector(keyboardNotification(notification:)),
                                           name: UIResponder.keyboardWillChangeFrameNotification,
                                           object: nil)        
}


deinit {
    NotificationCenter.default.removeObserver(self)
}


@objc func keyboardNotification(notification: NSNotification) {
    if let userInfo = notification.userInfo {
        // Get keyboard frame
        let keyboardFrame = (userInfo[UIResponder.keyboardFrameEndUserInfoKey] as! NSValue).cgRectValue

        // Set new bottom constraint constant
        let bottomConstraintConstant = keyboardFrame.origin.y >= UIScreen.main.bounds.size.height ? 0.0 : keyboardFrame.size.height

        // Set animation properties
        let duration = (userInfo[UIResponder.keyboardAnimationDurationUserInfoKey] as? NSNumber)?.doubleValue ?? 0
        let animationCurveRawNSN = userInfo[UIResponder.keyboardAnimationCurveUserInfoKey] as? NSNumber
        let animationCurveRaw = animationCurveRawNSN?.uintValue ?? UIView.AnimationOptions.curveEaseInOut.rawValue
        let animationCurve = UIView.AnimationOptions(rawValue: animationCurveRaw)

        // Animate the view you care about
        UIView.animate(withDuration: duration, delay: 0, options: animationCurve, animations: {
            self.bottomConstraint.constant = bottomConstraintConstant
            self.view.layoutIfNeeded()
        }, completion: nil)
    }
}

在编辑文本框时移动您的视图试试这个，我已经应用了这个，

选项1:—** **在Swift 5.0和iPhone X、XR、XS和XS Max中更新 使用NotificationCenter移动

在func viewWillAppear中注册这个通知(_ animated: Bool) 在func中注销此通知viewWillDisappear(_ animated: Bool)

注意:-如果你不取消注册，那么它将从子类调用，并将导致崩溃或其他。

override func viewWillAppear(_ animated: Bool) {
    super.viewWillAppear(animated)
    NotificationCenter.default.addObserver( self, selector: #selector(keyboardWillShow(notification:)), name:  UIResponder.keyboardWillShowNotification, object: nil )
}
override func viewWillDisappear(_ animated: Bool) {
    super.viewWillDisappear(animated)
    NotificationCenter.default.removeObserver(self, name: UIResponder.keyboardWillShowNotification, object: nil)
}

@objc func keyboardWillShow( notification: Notification) {
    if let keyboardFrame: NSValue = notification.userInfo?[UIResponder.keyboardFrameEndUserInfoKey] as? NSValue {
        var newHeight: CGFloat
        let duration:TimeInterval = (notification.userInfo![UIResponder.keyboardAnimationDurationUserInfoKey] as? NSNumber)?.doubleValue ?? 0
        let animationCurveRawNSN = notification.userInfo![UIResponder.keyboardAnimationCurveUserInfoKey] as? NSNumber
        let animationCurveRaw = animationCurveRawNSN?.uintValue ?? UIView.AnimationOptions.curveEaseInOut.rawValue
        let animationCurve:UIView.AnimationOptions = UIView.AnimationOptions(rawValue: animationCurveRaw)
        if #available(iOS 11.0, *) {
            newHeight = keyboardFrame.cgRectValue.height - self.view.safeAreaInsets.bottom
        } else {
            newHeight = keyboardFrame.cgRectValue.height
        }
        let keyboardHeight = newHeight  + 10 // **10 is bottom margin of View**  and **this newHeight will be keyboard height**
        UIView.animate(withDuration: duration,
                       delay: TimeInterval(0),
                       options: animationCurve,
                       animations: {
                        self.view.textViewBottomConstraint.constant = keyboardHeight **//Here you can manage your view constraints for animated show**
                        self.view.layoutIfNeeded() },
                       completion: nil)
    }
}

方案二:- 工作正常

func textFieldDidBeginEditing(textField: UITextField) {
        self.animateViewMoving(up: true, moveValue: 100)
}
func textFieldDidEndEditing(textField: UITextField) {
        self.animateViewMoving(up: false, moveValue: 100)
}

func animateViewMoving (up:Bool, moveValue :CGFloat){
    var movementDuration:NSTimeInterval = 0.3
    var movement:CGFloat = ( up ? -moveValue : moveValue)
    UIView.beginAnimations( "animateView", context: nil)
    UIView.setAnimationBeginsFromCurrentState(true)
    UIView.setAnimationDuration(movementDuration )
    self.view.frame = CGRectOffset(self.view.frame, 0,  movement)
    UIView.commitAnimations()
}

当键盘出现在Swift中时，我从这个源UITextField中得到了这个答案

在斯威夫特4——

func textFieldDidBeginEditing(_ textField: UITextField) {
        animateViewMoving(up: true, moveValue: 100)
    }

    func textFieldDidEndEditing(_ textField: UITextField) {
        animateViewMoving(up: false, moveValue: 100)
    }
    func animateViewMoving (up:Bool, moveValue :CGFloat){
        let movementDuration:TimeInterval = 0.3
        let movement:CGFloat = ( up ? -moveValue : moveValue)
        UIView.beginAnimations( "animateView", context: nil)
        UIView.setAnimationBeginsFromCurrentState(true)
        UIView.setAnimationDuration(movementDuration ) 
        self.view.frame = self.view.frame.offsetBy(dx: 0, dy: movement)
        UIView.commitAnimations()
    }

这是一个改进版的@JosephLord和@Hlung的回答。 无论你是否有标签栏，它都适用。 并且它可以完美地恢复由键盘移动到原始位置的视图。

// You have to set this up in storyboard first!. 
// It's a vertical spacing constraint between view and bottom of superview.
@IBOutlet weak var bottomSpacingConstraint: NSLayoutConstraint! 

override func viewDidLoad() {
        super.viewDidLoad()            

        //    Receive(Get) Notification
        NSNotificationCenter.defaultCenter().addObserver(self, selector: "keyboardNotification:", name: UIKeyboardWillShowNotification, object: nil)
        NSNotificationCenter.defaultCenter().addObserver(self, selector: "keyboardNotification:", name: UIKeyboardWillHideNotification, object: nil)


        self.originalConstraint = self.keyboardHeightLayoutConstraint?.constant //for original coordinate.
}

func keyboardNotification(notification: NSNotification) {
        let isShowing = notification.name == UIKeyboardWillShowNotification

        var tabbarHeight: CGFloat = 0
        if self.tabBarController? != nil {
            tabbarHeight = self.tabBarController!.tabBar.frame.height
        }
        if let userInfo = notification.userInfo {
            let endFrame = (userInfo[UIKeyboardFrameEndUserInfoKey] as? NSValue)?.CGRectValue()
            let duration:NSTimeInterval = (userInfo[UIKeyboardAnimationDurationUserInfoKey] as? NSNumber)?.doubleValue ?? 0
            let animationCurveRawNSN = userInfo[UIKeyboardAnimationCurveUserInfoKey] as? NSNumber
            let animationCurveRaw = animationCurveRawNSN?.unsignedLongValue ?? UIViewAnimationOptions.CurveEaseInOut.rawValue
            let animationCurve:UIViewAnimationOptions = UIViewAnimationOptions(rawValue: animationCurveRaw)
            self.keyboardHeightLayoutConstraint?.constant = isShowing ? (endFrame!.size.height - tabbarHeight) : self.originalConstraint!
            UIView.animateWithDuration(duration,
                delay: NSTimeInterval(0),
                options: animationCurve,
                animations: { self.view.layoutIfNeeded() },
                completion: nil)
        }
}