选择预测文本并将其添加到文本时，不会触发iOS textViewDidChange

Question

当我点击“Hello”或“He”时，不会触发textViewDidChange。

如何检测何时选择预测文本？

Answer 1

尝试使用shouldChangeTextInRange代替textViewDidChange 我尝试了它，它是用预测文本触发的

Answer 2

您是否设置了textView.delegate？

Answer 3

1. YourViewController<UITextViewDelegate>
2. 设置textView后，textView.delegate = self
3. func textViewDidChange(textView: UITextView)： func textViewDidChange(textView: UITextView) { //textView(Sender) if(textView == yourtextview) { //do something } }

Answer 4

当UITextView更改时，我必须使用NotificationCenter来获得通知。 我创建了UITextView的扩展以注册/注销这些通知。请记住，当您不再希望继续处理这些更改时（例如，在viewWillDisappear上，请致电取消注册。

import UIKit

extension UITextView {

    public func registerTextViewNotifications() {
        let center = NotificationCenter.default
        center.addObserver(self,
                           selector: #selector(textViewDidChangeWithNotification(_:)),
                           name: UITextView.textDidChangeNotification,
                           object: nil)
    }

    public func unregisterTextViewNotifications() {
        let center = NotificationCenter.default
        center.removeObserver(self,
                              name: UITextView.textDidChangeNotification,
                              object: nil)
    }

    @objc private func textViewDidChangeWithNotification(_ notification: Notification) {
        // Do something when edited
        print("Text: \(String(describing: text))")
    }

}

class ViewController: UIViewController {

    @IBOutlet var textView: UITextView!

    override func viewDidLoad() {
        super.viewDidLoad()
    }

    override func viewWillAppear(_ animated: Bool) {
        super.viewWillAppear(animated)
        textView.registerTextViewNotifications()
    }

    override func viewWillDisappear(_ animated: Bool) {
        super.viewWillDisappear(animated)
        textView.unregisterTextViewNotifications()
    }

}