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

这个实现(Swift 4)将给你的行为最接近Android的默认行为。Ie:当活动文本域在键盘下时,将视图向上移动,当用户切换到另一个视图时,无需关闭键盘。记住调用settextfielddelegate()。

public class DelegateProxy: NSObject, UITextFieldDelegate {

  private static let instance = DelegateProxies()

  weak var activeTextField: UITextField?
  var offset: CGFloat = 0
  weak var vc: UIViewController?
  var keyboardHeight: CGFloat = 0

  public static func getDelegate(root: UIViewController) -> DelegateProxies {
    instance.vc = root
    return instance
  }

  public static func getDelegate() -> DelegateProxies {
    return instance
  }

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


  public func textFieldShouldBeginEditing(_ textField: UITextField) -> Bool {

    self.activeTextField = textField

    let globalPointY: CGFloat = (textField.superview?.convert(textField.frame.origin, to: nil).y ?? CGFloat(0)) + textField.frame.height


    offset = UIScreen.main.bounds.height - globalPointY

    if keyboardHeight > 0 {
        vc?.moveViewUp(offsetFromKeyboard: keyboardHeight - offset)
    }

    return true
  }
}


extension UIViewController {

  private func setTextFieldDelegates(parentView: UIView) {
    for child in parentView.subviews {
        setTextFieldDelegates(parentView: child)
        (child as? UITextField)?.delegate = DelegateProxies.getDelegate(root: self)
    }
  }

  func registerAutoResizeOnKeyboardAppear(){
    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)
  }

  func unregisterAutoResizeOnKeyboard(){
    NotificationCenter.default.removeObserver(self, name: NSNotification.Name.UIKeyboardWillShow, object: nil)
    NotificationCenter.default.removeObserver(self, name: NSNotification.Name.UIKeyboardWillHide, object: nil)
  }

  @objc func keyboardWillShow(notification: NSNotification) {

    if let keyboardSize = (notification.userInfo?[UIKeyboardFrameEndUserInfoKey] as? NSValue)?.cgRectValue {
        let offsetFromKeyboard = keyboardSize.height - DelegateProxies.getDelegate().offset
        DelegateProxies.getDelegate().keyboardHeight = keyboardSize.height

        moveViewUp(offsetFromKeyboard: offsetFromKeyboard)
    }
  }

  func moveViewUp(offsetFromKeyboard: CGFloat){
    print("offset from keyboard: \(offsetFromKeyboard)")

    let moveOffset = offsetFromKeyboard + 8

    if offsetFromKeyboard > 0 {
        self.view.frame.origin.y = -moveOffset
    }

    if offsetFromKeyboard < 0 && view.frame.origin.y < 0 {
        self.view.frame.origin.y += -moveOffset
        if self.view.frame.origin.y > 0{
            self.view.frame.origin.y = 0
        }
    }
  }

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

其他回答

这个功能应该在Ios中内置,但是我们需要在外部做。 插入以下代码 *当textField在键盘下时移动视图, *当textField在键盘上方时不移动视图 *在需要时根据键盘的高度移动视图。 这在所有情况下都有效并经过测试。

import UIKit

class NamVcc: UIViewController, UITextFieldDelegate
{
    @IBOutlet weak var NamTxtBoxVid: UITextField!

    var VydTxtBoxVar: UITextField!
    var ChkKeyPadDspVar: Bool = false
    var KeyPadHytVal: CGFloat!

    override func viewDidLoad()
    {
        super.viewDidLoad()

        NamTxtBoxVid.delegate = self
    }

    override func viewWillAppear(animated: Bool)
    {
        NSNotificationCenter.defaultCenter().addObserver(self,
            selector: #selector(TdoWenKeyPadVyd(_:)),
            name:UIKeyboardWillShowNotification,
            object: nil);
        NSNotificationCenter.defaultCenter().addObserver(self,
            selector: #selector(TdoWenKeyPadHyd(_:)),
            name:UIKeyboardWillHideNotification,
            object: nil);
    }

    func textFieldDidBeginEditing(TxtBoxPsgVar: UITextField)
    {
        self.VydTxtBoxVar = TxtBoxPsgVar
    }

    func textFieldDidEndEditing(TxtBoxPsgVar: UITextField)
    {
        self.VydTxtBoxVar = nil
    }

    func textFieldShouldReturn(TxtBoxPsgVar: UITextField) -> Bool
    {
        self.VydTxtBoxVar.resignFirstResponder()
        return true
    }

    override func touchesBegan(touches: Set<UITouch>, withEvent event: UIEvent?)
    {
        view.endEditing(true)
        super.touchesBegan(touches, withEvent: event)
    }

    func TdoWenKeyPadVyd(NfnPsgVar: NSNotification)
    {
        if(!self.ChkKeyPadDspVar)
        {
            self.KeyPadHytVal = (NfnPsgVar.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.CGRectValue().height

            var NonKeyPadAraVar: CGRect = self.view.frame
            NonKeyPadAraVar.size.height -= self.KeyPadHytVal

            let VydTxtBoxCenVal: CGPoint? = VydTxtBoxVar?.frame.origin

            if (!CGRectContainsPoint(NonKeyPadAraVar, VydTxtBoxCenVal!))
            {
                self.ChkKeyPadDspVar = true
                UIView.animateWithDuration(1.0,
                    animations:
                    { self.view.frame.origin.y -= (self.KeyPadHytVal)},
                    completion: nil)
            }
            else
            {
                self.ChkKeyPadDspVar = false
            }
        }

    }

    func TdoWenKeyPadHyd(NfnPsgVar: NSNotification)
    {
        if (self.ChkKeyPadDspVar)
        {
            self.ChkKeyPadDspVar = false
            UIView.animateWithDuration(1.0,
                animations:
                { self.view.frame.origin.y += (self.KeyPadHytVal)},
                completion: nil)
        }
    }

    override func viewDidDisappear(animated: Bool)
    {
        super.viewWillDisappear(animated)
        NSNotificationCenter.defaultCenter().removeObserver(self)
        view.endEditing(true)
        ChkKeyPadDspVar = false
    }
}

|::|有时候视图会向下,在这种情况下使用高度+/- 150:

    NonKeyPadAraVar.size.height -= self.KeyPadHytVal + 150

    { self.view.frame.origin.y -= self.KeyPadHytVal  - 150},
                    completion: nil)

    { self.view.frame.origin.y += self.KeyPadHytVal  - 150},
                completion: nil)

我已经阅读了答案,并通过以下代码行解决了我的问题:

class ViewController: UIViewController, UITextFieldDelegate {

  @IBOutlet weak var titleField: UITextField!
  @IBOutlet weak var priceField: UITextField!
  @IBOutlet weak var detailsField: UTtextField!

  override func viewDidLoad() {
   super.viewDidLoad()
// Do not to forget to set the delegate otherwise the textFieldShouldReturn(_:)
// won't work and the keyboard will never be hidden.
   priceField.delegate = self
   titleField.delegate = self
   detailsField.delegate = self

   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)
  }

   func textFieldShouldReturn(_ textField: UITextField) -> Bool {
      self.view.endEditing(true)
      return false
   }

 func keyboardWillShow(notification: NSNotification) {
   var translation:CGFloat = 0
   if let keyboardSize = (notification.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.cgRectValue {
     if detailsField.isEditing{
       translation = CGFloat(-keyboardSize.height)
     }else if priceField.isEditing{
       translation = CGFloat(-keyboardSize.height / 3.8)
     }
   }
    UIView.animate(withDuration: 0.2) {
   self.view.transform = CGAffineTransform(translationX: 0, y: translation)
    }
  }


 func keyboardWillHide(notification: NSNotification) {
    UIView.animate(withDuration: 0.2) {
     self.view.transform = CGAffineTransform(translationX: 0, y: 0)
    } 
  }
}

我有几个UITextFields,并希望视图移动不同取决于哪个textField被点击。

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
    }
}

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)
  }
}

不是广告、促销或垃圾邮件,只是一个很好的解决方案。我知道这个问题有近30个答案,我很震惊,居然没有人提到过这个美丽的GitHub项目,它为你做了这一切,甚至更好。所有的答案只是向上移动视图。我刚刚用这个IQKeyboardManager解决了我所有的问题。它有13000多颗恒星。 如果你使用swift,只需将此添加到你的podfile中

pod 'IQKeyboardManagerSwift'

然后在你的AppDelegate.swift中导入IQKeyboardManagerSwift

import IQKeyboardManagerSwift

@UIApplicationMain
class AppDelegate: UIResponder, UIApplicationDelegate {

    var window: UIWindow?

    func application(application: UIApplication, didFinishLaunchingWithOptions launchOptions: [NSObject: AnyObject]?) -> Bool {

      IQKeyboardManager.shared.enable = true // just add this line

      return true
    }
}

添加一行IQKeyboardManager.shared.enable = true来启用它 如果您要进行生产,那么这个解决方案是必须的。