我有一个应用,它在视图的下半部分有一个文本框。 这意味着当我在文本框中输入时,键盘会覆盖文本框。

我如何在打字时向上移动视图,这样我就可以看到我键入的内容,然后在键盘消失时将它移回原来的位置?

我到处都看了,但所有的解似乎都在Obj-C中,我还不能完全转换。

任何帮助都将不胜感激。


当前回答

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
         }
    }

其他回答

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
    }
}

}

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

将这个添加到你的视图控制器中。效果非常好。只是调整数值。

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(sender: NSNotification) {
    self.view.frame.origin.y -= 150
}
@objc func keyboardWillHide(sender: NSNotification) {
    self.view.frame.origin.y += 150
}

Swift 3代码

var activeField: UITextField?

override func viewDidLoad() {
    super.viewDidLoad()

    NotificationCenter.default.addObserver(self, selector: #selector(ProfileViewController.keyboardWillShow), name: NSNotification.Name.UIKeyboardWillShow, object: nil)
    NotificationCenter.default.addObserver(self, selector: #selector(ProfileViewController.keyboardWillHide), name: NSNotification.Name.UIKeyboardWillHide, object: nil)
}

func textFieldDidBeginEditing(_ textField: UITextField){
    activeField = textField
}

func textFieldDidEndEditing(_ textField: UITextField){
    activeField = nil
}

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

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

这是我的解决方案(实际上这段代码是在你的视图中有几个文本字段的情况下,这也适用于当你有一个文本字段的情况下)

class MyViewController: UIViewController, UITextFieldDelegate {

@IBOutlet weak var firstTextField: UITextField!
@IBOutlet weak var secondTextField: UITextField!

var activeTextField: UITextField!
var viewWasMoved: Bool = false


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

override func viewDidDisappear(animated: Bool) {
    super.viewWillDisappear(animated)
    NSNotificationCenter.defaultCenter().removeObserver(self)
}

func textFieldDidBeginEditing(textField: UITextField) {
    self.activeTextField = textField
}

func textFieldDidEndEditing(textField: UITextField) {
    self.activeTextField = nil
}

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


func keyboardWillShow(notification: NSNotification) {

    let keyboardSize = (notification.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.CGRectValue()

    var aRect: CGRect = self.view.frame
    aRect.size.height -= keyboardSize!.height

    let activeTextFieldRect: CGRect? = activeTextField?.frame
    let activeTextFieldOrigin: CGPoint? = activeTextFieldRect?.origin

    if (!CGRectContainsPoint(aRect, activeTextFieldOrigin!)) {
        self.viewWasMoved = true
        self.view.frame.origin.y -= keyboardSize!.height
    } else {
        self.viewWasMoved = false
    }
}

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