swift 3.0插入在viewDidLoad()，这->

{

view addSubview (Your_messageInputConteinerView)。

    view.addConstraintWithFormat(format: "H:|[v0]|", views:Your_messageInputConteinerView)

    view.addConstraintWithFormat(format: "V:[v0(48)]", views:Your_messageInputConteinerView)

addobserver (self, selector: #selector(handleKeyboardNotification(notification:)))， name: NSNotification.Name。对象:nil)

addobserver (self, selector: #selector(handleKeyboardNotification(notification:)))，名称:.UIKeyboardWillHide，对象:nil)

bottomConstraint = NSLayoutConstraint(item: Your_messageInputConteinerView, attribute: .bottom, relatedBy: .equal, toItem: view, attribute: .bottom, multiplier: 1, constant: 0)

view.addConstraint(bottomConstraint!)

}

func handleKeyboardNotification(通知:通知){

if let userInfo = notification.userInfo {

    if let keyBoardFrame = (userInfo[UIKeyboardFrameEndUserInfoKey] as? NSValue)?.cgRectValue{

        print(keyBoardFrame)

        if bottomConstraint?.constant != CGFloat(0) {
                bottomConstraint?.constant = 0
                return
            }
     bottomConstraint?.constant = -keyBoardFrame.height
                           or
        self.view.frame.origin.y = -keyBoardFrame.height
    }
}

}

我需要在swift 4中移动一个UIView，当键盘打开和关闭。所有的答案都帮不了我。因为打开表情包时键盘高度会发生变化。所以我的代码是:

@objc func keyboardWillShow(sender: NSNotification) {

    if let keyboardFrame: NSValue = sender.userInfo?[UIKeyboardFrameEndUserInfoKey] as? NSValue {

        let keyboardRectangle = keyboardFrame.cgRectValue
        let keyboardHeight = keyboardRectangle.height

        if(self.oldHeight == keyboardHeight){
            self.sendingView.frame.origin.y -= keyboardHeight
            self.oldHeight = keyboardHeight
        }
        else{
            self.sendingView.frame.origin.y += self.oldHeight
            self.sendingView.frame.origin.y -= keyboardHeight
            self.oldHeight = keyboardHeight
        }
    }
}

@objc func keyboardWillHide(sender: NSNotification) {

    if let keyboardFrame: NSValue = sender.userInfo?[UIKeyboardFrameEndUserInfoKey] as? NSValue {

        let keyboardRectangle = keyboardFrame.cgRectValue
        let keyboardHeight = keyboardRectangle.height

        self.sendingView.frame.origin.y += keyboardHeight

    }
}

和在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);

自我。oldHeight = CGFloat()并定义为类顶部的字段。

我看到所有的答案都是通过键盘高度的值移动视图本身。好吧，我有一个详细的答案，这可能是有用的，如果你正在使用约束即自动布局，移动一个视图通过改变其约束值(底部或顶部约束为例)由一个预定义的值或你可以使用键盘大小值。

在这个例子中，我使用底部约束从文本字段到底部布局视图的初始值为175。

@IBOutlet weak var bottomConstraint: NSLayoutConstraint!

override func viewDidLoad() {
    super.viewDidLoad()        
    NSNotificationCenter.defaultCenter().addObserver(self, selector: Selector("keyboardWillShow:"), name:UIKeyboardWillShowNotification, object: nil);
    NSNotificationCenter.defaultCenter().addObserver(self, selector: Selector("keyboardWillHide:"), name:UIKeyboardWillHideNotification, object: nil);
}

func keyboardWillShow(notification: NSNotification) {
    //To retrieve keyboard size, uncomment following line
    //let keyboardSize = (notification.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.CGRectValue()
    bottomConstraint.constant = 260
    UIView.animateWithDuration(0.3) {
        self.view.layoutIfNeeded()
    }
}

func keyboardWillHide(notification: NSNotification) {
    //To retrieve keyboard size, uncomment following line
    //let keyboardSize = (notification.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.CGRectValue()
    bottomConstraint.constant = 175
    UIView.animateWithDuration(0.3) {
        self.view.layoutIfNeeded()
    }
}

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)
}

如果你在同一个VC中有2个或更多的文本字段，用户点击其中一个，然后点击另一个，不调用keyboardWillHide函数，视图会再向上一次，这是不必要的，因为你会有键盘，一个空格，它有键盘的高度，然后视图，使用我编辑的答案中的代码:

override func viewDidLoad() {       
    super.viewDidLoad()
    NSNotificationCenter.defaultCenter().addObserver(self, selector: Selector("keyboardWillShow:"), name: UIKeyboardWillShowNotification, object: nil)
    NSNotificationCenter.defaultCenter().addObserver(self, selector: Selector("keyboardWillHide:"), name: UIKeyboardWillHideNotification, object: nil)
}

func keyboardWillShow(notification: NSNotification) {
    if let keyboardSize = (notification.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.CGRectValue() {
        self.view.frame.origin.y -= keyboardSize.height
    }
}

func keyboardWillHide(notification: NSNotification) {
    if let keyboardSize = (notification.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.CGRectValue() {
        self.view.frame.origin.y += keyboardSize.height
    }
}

为了解决这个问题，将两个函数"KeyboardWillShow/Hide"替换为:

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

func keyboardWillHide(notification: NSNotification) {
    if let keyboardSize = (notification.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.CGRectValue() {
        if view.frame.origin.y != 0 {
            self.view.frame.origin.y += keyboardSize.height
        }
    }
}

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!