在容器视图之间从TextField中委托文本

我试图通过文本forms一个TextField到另一个TextField。 它们都位于不同的ContainerView中。 用户可以通过分段控制在不同的ContainerView之间切换（因此，我的所有ContainerView都位于具有分段控制的ViewController中）。

我试图用委托来做到这一点：每当TextFieldOne中的文本发生变化，这种变化应该会影响另一个textField，所以，我尝试在第一个容器中的TextField上使用“Value Changed”事件的操作：

protocol AddOneWordViewControllerDelegate: class { func changeTexeValue(_ text: String) } class AddOneWordViewController: UIViewController, UITextFieldDelegate { @IBOutlet weak var oneWordAddWord: UITextField! weak var delegate: AddOneWordViewControllerDelegate? override func viewDidLoad() { super.viewDidLoad() self.oneWordAddWord.delegate = self } override func didReceiveMemoryWarning() { super.didReceiveMemoryWarning() } override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) { self.view.endEditing(true) } func textFieldShouldReturn(_ textField: UITextField) -> Bool { textField.resignFirstResponder() return true } @IBAction func addOneWordWordChanged(_ sender: UITextField) { guard let delegate = delegate else { return } delegate.changeTexeValue(oneWordAddWord.text!) } } 

这里是我的第二个容器，其中textField应该被改变：

  class AddTwoWordsViewController: UIViewController, UITextFieldDelegate, AddOneWordViewControllerDelegate { @IBOutlet weak var twoWordsAddWord: UITextField! override func viewDidLoad() { super.viewDidLoad() self.twoWordsAddWord.delegate = self let app = UIApplication.shared.delegate! as! AppDelegate if let viewControllers = app.window?.rootViewController?.childViewControllers { viewControllers.forEach({ (vc) in if let cont = vc as? AddOneWordViewController { cont.delegate = self } }) } } override func didReceiveMemoryWarning() { super.didReceiveMemoryWarning() } override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) { self.view.endEditing(true) } func textFieldShouldReturn(_ textField: UITextField) -> Bool { textField.resignFirstResponder() return true } func changeTexeValue(_ text: String) { twoWordsAddWord.text = text } } 

我遵循这个问题的结构，但没有成功。 这里有什么问题？

我的主视图控制器：

 import UIKit import Firebase class WordViewController: UIViewController { @IBOutlet weak var selectedIndex: UISegmentedControl! @IBOutlet weak var oneWord: UIView! @IBOutlet weak var twoWords: UIView! @IBOutlet weak var threeWords: UIView! @IBOutlet weak var fourWords: UIView! var ref: DatabaseReference? var addOneWordViewController: AddOneWordViewController! var addTwoWordsViewController: AddTwoWordsViewController! var addThreeWordsViewController: AddThreeWordsViewController! var addFourWordsViewController: AddFourWordsViewController! override func prepare(for segue: UIStoryboardSegue, sender: Any?) { if segue.identifier == "oneWord" { addOneWordViewController = segue.destination as! AddOneWordViewController } else if segue.identifier == "twoWords" { addTwoWordsViewController = segue.destination as! AddTwoWordsViewController } else if segue.identifier == "threeWords" { addThreeWordsViewController = segue.destination as! AddThreeWordsViewController } else if segue.identifier == "fourWords" { addFourWordsViewController = segue.destination as! AddFourWordsViewController } } override func viewDidLoad() { super.viewDidLoad() ref = Database.database().reference() self.oneWord.alpha = 1 // setting the initial view of the first Index of Sigment View to the First Container View self.twoWords.alpha = 0 self.threeWords.alpha = 0 self.fourWords.alpha = 0 } @IBAction func showWord(_ sender: UISegmentedControl) { // making one of the four container view vivsible depending on the Index of Segment Controller if sender.selectedSegmentIndex == 0 { UIView.animate(withDuration: 0.5, animations: { self.oneWord.alpha = 1 self.twoWords.alpha = 0 self.threeWords.alpha = 0 self.fourWords.alpha = 0 }) } else if sender.selectedSegmentIndex == 1 { UIView.animate(withDuration: 0.5, animations: { self.oneWord.alpha = 0 self.twoWords.alpha = 1 self.threeWords.alpha = 0 self.fourWords.alpha = 0 }) } else if sender.selectedSegmentIndex == 2 { UIView.animate(withDuration: 0.5, animations: { self.oneWord.alpha = 0 self.twoWords.alpha = 0 self.threeWords.alpha = 1 self.fourWords.alpha = 0 }) } else { UIView.animate(withDuration: 0.5, animations: { self.oneWord.alpha = 0 self.twoWords.alpha = 0 self.threeWords.alpha = 0 self.fourWords.alpha = 1 }) } } override func didReceiveMemoryWarning() { super.didReceiveMemoryWarning() } @IBAction func addWord(_ sender: Any) { if selectedIndex.selectedSegmentIndex == 0 { guard let text = addOneWordViewController.oneWordAddWord.text, !text.isEmpty else { return } ref?.child("LearnedWords").child(addOneWordViewController.oneWordAddWord.text!).setValue(addOneWordViewController.oneWordAddWord.text) presentingViewController?.dismiss(animated: true, completion: nil) } else if selectedIndex.selectedSegmentIndex == 1 { guard let text = addTwoWordsViewController.twoWordsAddWord.text, !text.isEmpty else { return } ref?.child("LearnedWords").child(addTwoWordsViewController.twoWordsAddWord.text!).setValue(addTwoWordsViewController.twoWordsAddWord.text) presentingViewController?.dismiss(animated: true, completion: nil) } else if selectedIndex.selectedSegmentIndex == 2 { guard let text = addThreeWordsViewController.threeWordsAddWord.text, !text.isEmpty else { return } ref?.child("LearnedWords").child(addThreeWordsViewController.threeWordsAddWord.text!).setValue(addThreeWordsViewController.threeWordsAddWord.text) presentingViewController?.dismiss(animated: true, completion: nil) } else { guard let text = addFourWordsViewController.fourWordsAddWord.text, !text.isEmpty else { return } ref?.child("LearnedWords").child(addFourWordsViewController.fourWordsAddWord.text!).setValue(addFourWordsViewController.fourWordsAddWord.text) presentingViewController?.dismiss(animated: true, completion: nil) } } @IBAction func cancelWord(_ sender: Any) { presentingViewController?.dismiss(animated: true, completion: nil) // closing this View } }