从 Xamarin.Forms 中的 BindableRadioGroup 中取消选择选项

我正在使用XLabs项目中的这个控件。绑定和选择工作正常，但我在某种调查中使用此控件，我想在客户端单击按钮查看下一个问题后取消选择Next答案（此控件中的选项）。任何想法如何做到这一点？

<controls:BindableRadioGroup 
                ItemsSource="{Binding Answers}"
                SelectedIndex="{Binding AnswerSelected, Mode=TwoWay}"
                Style="{StaticResource radioGroupStyle}" />

绑定到按钮的命令：

public IAsyncCommand NextCommand
    {
        get
        {
            return new AwaitableDelegateCommand(async () => await Next(), CanGoToNextQuestion);
        }
    }

和方法：

private async Task Next()
    {
        CurrentQuestionIndex++;
        AnsweredQuestions.Add(
            new QuestionDto
            {
                QuestionId = CurrentQuestion.QuestionId,
                QuestionText = CurrentQuestion.QuestionText,
                Answer = Answers.ElementAt(AnswerSelected).Value,
            });
            // some stuff here

        AnswerSelected = -1;
    }
    private bool CanGoToNextQuestion()
    {
        return AnswerSelected != -1;
    }

    void Handle_Clicked(object sender, System.EventArgs e)
    {
        ClearRadioGroup();
    }
    private void ClearRadioGroup()
    {
        foreach (var child in grupa.Children)
        {
            var radio = (CustomRadioButton)child;
            radio.Checked = false;
        }
    }