斯威夫特5.0:

经过4-5个小时的战斗，我得到了一个简单的扩展UIViewController与简单的代码，就像魅力

*当TextField在键盘上方时，视图不应该移动

*不需要设置常量值为NSLayoutConstraint

*无需第三方库

*无需动画代码

*适用于tableview

*这适用于自动布局/自动调整大小

extension UIViewController {
    func addKeyboardObserver() {
        NotificationCenter.default.addObserver(self, selector: #selector(keyboardNotifications(notification:)),
                                               name: UIResponder.keyboardWillChangeFrameNotification,
                                               object: nil)
    }

    func removeKeyboardObserver(){
        NotificationCenter.default.removeObserver(self, name: UIResponder.keyboardWillChangeFrameNotification, object: nil)
    }

    // This method will notify when keyboard appears/ dissapears
    @objc func keyboardNotifications(notification: NSNotification) {

        var txtFieldY : CGFloat = 0.0  //Using this we will calculate the selected textFields Y Position
        let spaceBetweenTxtFieldAndKeyboard : CGFloat = 5.0 //Specify the space between textfield and keyboard


        var frame = CGRect(x: 0, y: 0, width: 0, height: 0)
        if let activeTextField = UIResponder.currentFirst() as? UITextField ?? UIResponder.currentFirst() as? UITextView {
            // Here we will get accurate frame of textField which is selected if there are multiple textfields
            frame = self.view.convert(activeTextField.frame, from:activeTextField.superview)
            txtFieldY = frame.origin.y + frame.size.height
        }

        if let userInfo = notification.userInfo {
            // here we will get frame of keyBoard (i.e. x, y, width, height)
            let keyBoardFrame = (userInfo[UIResponder.keyboardFrameEndUserInfoKey] as? NSValue)?.cgRectValue
            let keyBoardFrameY = keyBoardFrame!.origin.y
            let keyBoardFrameHeight = keyBoardFrame!.size.height

            var viewOriginY: CGFloat = 0.0
            //Check keyboards Y position and according to that move view up and down
            if keyBoardFrameY >= UIScreen.main.bounds.size.height {
                viewOriginY = 0.0
            } else {
                // if textfields y is greater than keyboards y then only move View to up
                if txtFieldY >= keyBoardFrameY {

                    viewOriginY = (txtFieldY - keyBoardFrameY) + spaceBetweenTxtFieldAndKeyboard

                    //This condition is just to check viewOriginY should not be greator than keyboard height
                    // if its more than keyboard height then there will be black space on the top of keyboard.
                    if viewOriginY > keyBoardFrameHeight { viewOriginY = keyBoardFrameHeight }
                }
            }

            //set the Y position of view
            self.view.frame.origin.y = -viewOriginY
        }
    }
}

添加这个扩展的UIResponder得到哪个TextField被选中

extension UIResponder {

    static weak var responder: UIResponder?

    static func currentFirst() -> UIResponder? {
        responder = nil
        UIApplication.shared.sendAction(#selector(trap), to: nil, from: nil, for: nil)
        return responder
    }

    @objc private func trap() {
        UIResponder.responder = self
    }
}

然后在你的任何ViewController中使用这个

   override func viewWillAppear(_ animated: Bool) {
        self.addKeyboardObserver()
    }

    override func viewWillDisappear(_ animated: Bool) {
        self.removeKeyboardObserver()
    }

在func viewWillAppear中注册这个通知(_ animated: Bool) 在func中注销此通知viewWillDisappear(_ animated:Bool) 下载演示文件

这个视频教程是最好的。7分钟长，会很有意义。这样一个简单的解决方案，当你有多个文本字段，并希望滚动视图移动“x”数量的像素时，特定的文本字段被点击。

https://youtu.be/VuiPGJOEBH4

就这些步骤:

-把你所有的文本字段放在一个滚动视图中，约束到视图的边缘。

-连接所有的文本字段和滚动视图作为视图控制器的委托。

-用IBOutlet连接所有文本字段和滚动视图。

class ViewController: UIViewController, UITextFieldDelegate {

添加UITextFieldDelegate协议到你的类中

@IBOutlet var stateAddress: UITextField!
@IBOutlet var zipAddress: UITextField!
@IBOutlet var phoneNumber: UITextField!
@IBOutlet var vetEmailAddress: UITextField!    
@IBOutlet weak var scrollView: UIScrollView!

-在swift文件中添加UITextFieldDelegate方法:

func textFieldShouldReturn(textField: UITextField) -> Bool {

    textField.resignFirstResponder()
    return true
}


func textFieldDidBeginEditing(textField: UITextField) {

    if (textField == self.stateAddress) {
        scrollView.setContentOffset(CGPointMake(0, 25), animated: true)
    }
    else if (textField == self.zipAddress) {
        scrollView.setContentOffset(CGPointMake(0, 57), animated: true)
    }
    else if (textField == self.phoneNumber) {
        scrollView.setContentOffset(CGPointMake(0, 112), animated: true)
    }
    else if (textField == self.vetEmailAddress) {
        scrollView.setContentOffset(CGPointMake(0, 142), animated: true)
    }
}

func textFieldDidEndEditing(textField: UITextField) {

    scrollView.setContentOffset(CGPointMake(0, 0), animated: true)
}

第一种方法只是激活键盘上的返回按钮来关闭键盘。第二个是当你点击到任何特定的文本域，然后设置你的滚动视图滚动的距离的y偏移(我的是基于我的视图控制器上的y位置25,57,112,142)。最后一个说，当你从键盘上点击时，滚动视图会回到原来的位置。

我使我的视图像素完美的这种方式!

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)
  }
}

对于黑屏错误(Swift 4和4.2)。

我解决了黑屏的问题。在验证方案中，敲击后键盘高度变化，导致黑屏。

必须使用UIKeyboardFrameEndUserInfoKey而不是UIKeyboardFrameBeginUserInfoKey

var isKeyboardAppear = false

override func viewDidLoad() {
    super.viewDidLoad() 
    NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillShow), name: NSNotification.Name.UIKeyboardWillShow, object: nil)
    NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillHide), name: NSNotification.Name.UIKeyboardWillHide, object: nil)
}

@objc func keyboardWillShow(notification: NSNotification) {
    if !isKeyboardAppear {
        if let keyboardSize = (notification.userInfo?[UIKeyboardFrameEndUserInfoKey] as? NSValue)?.cgRectValue {
            if self.view.frame.origin.y == 0{
                self.view.frame.origin.y -= keyboardSize.height
            }
        }
        isKeyboardAppear = true
    }
}

@objc func keyboardWillHide(notification: NSNotification) {
    if isKeyboardAppear {
        if let keyboardSize = (notification.userInfo?[UIKeyboardFrameEndUserInfoKey] as? NSValue)?.cgRectValue {
            if self.view.frame.origin.y != 0{
                self.view.frame.origin.y += keyboardSize.height
            }
        }
         isKeyboardAppear = false
    }
}

我做了一个椰子荚来简化问题:

https://github.com/xtrinch/KeyboardLayoutHelper

如何使用:

做一个自动布局底部约束，在模块KeyboardLayoutHelper中给它一个KeyboardLayoutConstraint类，pod将做必要的工作来增加它，以适应出现和消失的键盘。关于如何使用它(我做了两个:一个scrollView内的textFields，和垂直居中的textFields与两个基本视图-登录和注册)的例子项目。

底部布局约束可以是容器视图，textField本身，任何你能想到的。

对我有用

override func viewDidLoad() {

        super.viewDidLoad()

        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)
}

 var isScroll = false


@objc func keyboardWillShow(sender: NSNotification) {
    if( !isScroll  ){
        self.view.frame.origin.y -= 150
        isScroll = true
    }
}
@objc func keyboardWillHide(sender: NSNotification) {
    if( isScroll  ){
        self.view.frame.origin.y += 150
        isScroll = false
    }
}