如何根据android studio中保存在共享首选项中的单选按钮id启用单选组的特定单选按钮

我正在开发测验应用程序。其中上一个问题和下一个问题有两个按钮。我想做的是当用户从选项中选择答案（选项有4个单选按钮）并尝试下一个问题时，但如果用户想查看上一个问题，则应启用用户以前选择的同一个单选按钮。为此，我使用共享首选项来存储选定的单选按钮id。 这是我的密码： 有关“下一步”按钮，请单击：

 nextButton.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            int radioSelected = radioGroup.getCheckedRadioButtonId();
            int userSelection = getSelectedAnswer(radioSelected);

            sharedPreferences=getSharedPreferences(MyPREFERENCES,MODE_PRIVATE);
            SharedPreferences.Editor editor=sharedPreferences.edit();
            editor.putInt("Ans",userSelection);
            editor.commit();
            int correctAnswerForQuestion =firstQuestion.getCorrectAnswer();
            if(userSelection == correctAnswerForQuestion)
            {
                Toast.makeText(getApplicationContext(),"Correct Answer",Toast.LENGTH_LONG).show();
                currentQuizQuestion++;

                if(currentQuizQuestion>=quizCount)
                {
                    Toast.makeText(getApplicationContext(),"End of quiz",Toast.LENGTH_LONG).show();
                    return;
                }
                else
                {
                    firstQuestion=parsedObject.get(currentQuizQuestion);
                    txtquestion.setText(firstQuestion.getQuestion());
                    String[] possibleAnswers=firstQuestion.getAnswers().split(",");
                    uncheckedRadioButton();
                    optionOne.setText(possibleAnswers[0]);
                    optionTwo.setText(possibleAnswers[1]);
                    optionThree.setText(possibleAnswers[2]);
                    optionFour.setText(possibleAnswers[3]);
                }
            }
            else
            {
                Toast.makeText(getApplicationContext(),"You choose wrong answer",Toast.LENGTH_LONG).show();
                currentQuizQuestion++;
                firstQuestion=parsedObject.get(currentQuizQuestion);
                txtquestion.setText(firstQuestion.getQuestion());
                String[] possibleAnswers=firstQuestion.getAnswers().split(",");
               uncheckedRadioButton();
                optionOne.setText(possibleAnswers[0]);
                optionTwo.setText(possibleAnswers[1]);
                optionThree.setText(possibleAnswers[2]);
                optionFour.setText(possibleAnswers[3]);
            }
        }
    });

对于“上一步”按钮：

previousButton.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {

            currentQuizQuestion--;
            if(currentQuizQuestion<0)
            {
                return;
            }
           checkedRadioButton();
            firstQuestion=parsedObject.get(currentQuizQuestion);
            txtquestion.setText(firstQuestion.getQuestion());
            String[] possibleAnswers=firstQuestion.getAnswers().split(",");
            optionOne.setText(possibleAnswers[0]);
            optionTwo.setText(possibleAnswers[1]);
            optionThree.setText(possibleAnswers[2]);
            optionFour.setText(possibleAnswers[3]);

        }
    });
    JSON_DATA_WEB_CALL();

}
 private void checkedRadioButton() {
    int ans=1;
    int ans1=sharedPreferences.getInt("Ans",ans);



   if(optionOne.getId()==ans1)
   {

        optionOne.setChecked(true);


    }
}

previousButton.setOnClickListener（新视图.OnClickListener（）{
@凌驾
公共void onClick（视图）{
当前的问题--；
如果（currentQuizQuestion将标签添加到每个单选按钮选项optionOne.setTag（“回答标签”，“一”）。
存储所选标签，并将radiobuttons.getTag（“应答标签”）与存储的标签进行比较