如何将“隐藏/显示文本”按钮添加到“材质组件”文本字段-Swift

Question

我想在Swift的Material Components Textfield中添加一个显示/隐藏文本按钮。我确实要注意，由于对Material Components的不良，不清楚和不直观的使用，使其在Swift中不是最佳选择，并降低了整体代码质量。但是，我必须使用它。我已经用一个小时的时间在Google上进行了搜索，因此，如果有人可以简单地解释一下，那就太好了。这是我当前的代码：

@IBOutlet weak var usernameTextField: MDCTextField! {
    didSet {
        usernameController = MDCTextInputControllerOutlined(textInput: usernameTextField)
        let colorScheme = MDCSemanticColorScheme()
        colorScheme.primaryColor = UIColor(named: "ECH Blue")!
        colorScheme.onSurfaceColor = UIColor(named: "ECH Dark Grey")!
        let containerScheme = MDCContainerScheme()
        containerScheme.colorScheme = colorScheme
        usernameController?.applyTheme(withScheme: containerScheme)
        usernameTextField.addTarget(self, action: #selector(textFieldDidChange(_:)), for: UIControl.Event.editingChanged)
        usernameTextField.delegate = self
    }
}
@IBOutlet weak var passwordTextField: MDCTextField! {
    didSet{
        passwordController = MDCTextInputControllerOutlined(textInput: passwordTextField)
        let colorScheme = MDCSemanticColorScheme()
        colorScheme.primaryColor = UIColor(named: "ECH Blue")!
        colorScheme.onSurfaceColor = UIColor(named: "ECH Dark Grey")!
        let containerScheme = MDCContainerScheme()
        containerScheme.colorScheme = colorScheme
        passwordController?.applyTheme(withScheme: containerScheme)
        passwordTextField.addTarget(self, action: #selector(textFieldDidChange(_:)), for: UIControl.Event.editingChanged)
        passwordTextField.isSecureTextEntry = true
        passwordTextField.delegate = self
    }
}

请注意，此示例的实现不佳的github：https://github.com/material-components/material-components-ios-codelabs/blob/master/MDC-101/Swift/Complete/Shrine/Shrine/LoginViewController.swift不能执行此操作，并且存在错误。