Question

问题是仅在选择“文本字段”时才应显示“眼睛按钮”。我已经尝试过使用“ isFirstResponder”，但这似乎不起作用。有什么想法如何处理吗？在下面的图片中，未选择文本字段。

更新

委托函数“密码确实已更改”可以正常工作。我唯一需要的是，如果不再选择文本字段，则按钮应该隐藏。添加委托函数“ beging”或“ endEditing”不起作用。如果用户键入某些内容，然后取消选择该文本字段并再次选择它，这将导致另一个失败，即删除文本。

@IBAction func passwordDidChange(_ sender: Any) {
    if self.passwordTextField.text == "" && self.passwordTextField.isFirstResponder != true{
        self.eyeOpenButton.isHidden = true
    }else {
        self.eyeOpenButton.isHidden = false
    }

Answer 1

您可以尝试这样的事情。

class ViewController: UIViewController, UITextFieldDelegate {

    @IBOutlet weak var passwordTextField: UITextField!

    override func viewDidLoad() {
        super.viewDidLoad()
        self.eyeOpenButton.isHidden = true
        passwordTextField.delegate = self
    }

    // calls when textfield becomes 1st responder
    func textFieldShouldBeginEditing(_ textField: UITextField) -> Bool {
        switch textField {
        case passwordTextField:

            if passwordTextField.text != "" {
                self.eyeOpenButton.isHidden = !self.eyeOpenButton.isHidden
            } else {
                self.eyeOpenButton.isHidden = !self.eyeOpenButton.isHidden
            }

            break
        default:
            break
        }
        return true
    }

    //Calls when the text fields resigns first responder
    func textFieldShouldEndEditing(_ textField: UITextField) -> Bool {

        if textField == passwordTextField {
            if passwordTextField.text != "" {
                self.eyeOpenButton.isHidden = !self.eyeOpenButton.isHidden
            } else {
                self.eyeOpenButton.isHidden = !self.eyeOpenButton.isHidden
            }
        }
        return true
    }

    // Check all the input user has with the keyboard.
    func textField(_ textField: UITextField, shouldChangeCharactersIn range: NSRange, replacementString string: String) -> Bool {
        if let passwordTextField = passwordTextField {

            if passwordTextField.text?.count ?? 0 > 0 {
                self.eyeOpenButton.isHidden = !self.eyeOpenButton.isHidden
            }

            if passwordTextField.text?.count == 0 {
                 self.eyeOpenButton.isHidden = !self.eyeOpenButton.isHidden
            }
        }

        return true
    }

    func textFieldShouldReturn(_ textField: UITextField) -> Bool {
        for textField in self.view.subviews where textField is UITextField {
            textField.resignFirstResponder()
        }
        return true
    }
}

Answer 2

您需要使用UITextfieldDelegate方法进行处理。实现这些方法并听取更改并采取相应措施。

检查UITextfield是否处于活动状态

2 个答案: