public override void OnValueChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
        {
            if (!(d is PasswordBox passwordBox))
            {
                return;
            }

            passwordBox.PasswordChanged -= PasswordBox_PasswordChanged;

            if ((bool)e.NewValue)
            {
                HasTextProperty.SetValue(passwordBox);

                passwordBox.PasswordChanged += PasswordBox_PasswordChanged;
            }
        }
 private void PasswordBox_PasswordChanged(object sender, RoutedEventArgs e) =>
 HasTextProperty.SetValue((PasswordBox)sender);