how to store seleced checkbox values in array list in android

I have created simple quiz app. In that I want to get true value of checkbox. there are three checkbox questions. Now how to get right value of selected checkbox using ArrayList. So when multiple answers are selected by the user I need to store them in an arraylist and need to compare the selected answers with that in database. In my code I am storing the selected value id's one by one but at a time it is storing only one value. How to store all the selected checkbox id's in my arraylist?

My code:

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<ScrollView xmlns:android="http://ift.tt/nIICcg"
xmlns:tools="http://ift.tt/LrGmb4"
android:layout_width="match_parent"
android:layout_height="match_parent">

<LinearLayout
    android:id="@+id/activity_main"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:background="@drawable/background"
    android:orientation="vertical"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context="com.pujadudhat.quizapp.MainActivity">

    <TextView
        android:id="@+id/tv_que1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="@string/que_1" />

    <RadioGroup
        android:id="@+id/rg_que1"
        android:layout_width="match_parent"
        android:layout_height="wrap_content">

        <RadioButton
            android:id="@+id/rb_opt1"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginTop="10dp"
            android:onClick="questionOne"
            android:text="@string/rb_opt1" />

        <RadioButton
            android:id="@+id/rb_opt2"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:onClick="questionOne"
            android:text="@string/rb_opt2" />

        <RadioButton
            android:id="@+id/rb_opt3"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:onClick="questionOne"
            android:text="@string/rb_opt3" />
    </RadioGroup>

    <TextView
        android:id="@+id/tv_que2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="@dimen/activity_horizontal_margin"
        android:text="@string/que_2" />

    <RadioGroup
        android:id="@+id/rg_que2"
        android:layout_width="match_parent"
        android:layout_height="wrap_content">

        <RadioButton
            android:id="@+id/rb_opt1_2"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginTop="10dp"
            android:onClick="questionTwo"
            android:text="@string/rb_opt1_2" />

        <RadioButton
            android:id="@+id/rb_opt2_2"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:onClick="questionTwo"
            android:text="@string/rb_opt2_2" />

        <RadioButton
            android:id="@+id/rb_opt3_2"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:onClick="questionTwo"
            android:text="@string/rb_opt3_2" />
    </RadioGroup>

    <TextView
        android:id="@+id/tv_que3"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="@dimen/activity_horizontal_margin"
        android:text="@string/que_3" />

    <RadioGroup
        android:id="@+id/rg_que3"
        android:layout_width="match_parent"
        android:layout_height="wrap_content">

        <RadioButton
            android:id="@+id/rb_opt1_3"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginTop="10dp"
            android:onClick="questionThree"
            android:text="@string/rb_opt1_3" />

        <RadioButton
            android:id="@+id/rb_opt2_3"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:onClick="questionThree"
            android:text="@string/rb_opt2_3" />

        <RadioButton
            android:id="@+id/rb_opt3_3"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:onClick="questionThree"
            android:text="@string/rb_opt3_3" />
    </RadioGroup>

    <TextView
        android:id="@+id/tv_que4"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="@dimen/activity_horizontal_margin"
        android:text="@string/que_4" />

    <CheckBox
        android:id="@+id/cb_prime"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:onClick="questionFour"
        android:text="@string/cb_opt1_4" />

    <CheckBox
        android:id="@+id/cb_prime2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:onClick="questionFour"
        android:text="@string/cb_opt2_4" />

    <CheckBox
        android:id="@+id/cb_prime3"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:onClick="questionFour"
        android:text="@string/cb_opt3_4" />

    <TextView
        android:id="@+id/tv_que5"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="@dimen/activity_horizontal_margin"
        android:text="@string/que_5" />

    <CheckBox
        android:id="@+id/cb_composite"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:onClick="questionFive"
        android:text="@string/cb_opt1_5" />

    <CheckBox
        android:id="@+id/cb_composite2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:onClick="questionFive"
        android:text="@string/cb_opt2_5" />

    <CheckBox
        android:id="@+id/cb_composite3"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:onClick="questionFive"
        android:text="@string/cb_opt3_5" />

    <TextView
        android:id="@+id/tv_que6"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="@dimen/activity_horizontal_margin"
        android:text="@string/que_6" />

    <CheckBox
        android:id="@+id/cb_multiple"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:onClick="questionSix"
        android:text="@string/cb_opt1_6" />

    <CheckBox
        android:id="@+id/cb_multiple2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:onClick="questionSix"
        android:text="@string/cb_opt2_6" />

    <CheckBox
        android:id="@+id/cb_multiple3"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:onClick="questionSix"
        android:text="@string/cb_opt3_6" />

    <TextView
        android:id="@+id/tv_logo"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="@dimen/activity_horizontal_margin"
        android:text="@string/que_7" />

    <EditText
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="@dimen/activity_horizontal_margin"
        android:hint="@string/hint" />

    <ImageView
        android:layout_width="250dp"
        android:layout_height="250dp"
        android:src="@drawable/rolex_logo" />

    <TextView
        android:id="@+id/tv_score"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center" />

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="@dimen/activity_horizontal_margin"
        android:orientation="horizontal">

        <Button
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_gravity="center_horizontal"
            android:layout_weight="1"
            android:onClick="calsulateScore"
            android:text="@string/btn_text" />



        <Button
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_gravity="center"
            android:layout_weight="1"
            android:onClick="resetScore"
            android:text="@string/btn_reset" />
    </LinearLayout>
</LinearLayout>

MainActivity.java

package com.pujadudhat.quizapp;

import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.RadioButton;
import android.widget.Toast;

public class MainActivity extends AppCompatActivity {

private int myScore = 0;
boolean que1;
boolean que2;
boolean que3;


@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
}

/**
 * Get Answer for que. #1
 */

public void questionOne(View view) {

    RadioButton opt1RadioButton = (RadioButton) findViewById(R.id.rb_opt1);
    que1 = opt1RadioButton.isChecked();

    if (opt1RadioButton.isChecked()) {

        myScore = myScore + 1;
        Toast.makeText(getApplicationContext(), "Right!", Toast.LENGTH_SHORT).show();

    } else {
        Toast.makeText(getApplicationContext(), "Wrong!", Toast.LENGTH_SHORT).show();
    }
}

public void questionTwo(View view){
    RadioButton opt2RadioButton = (RadioButton) findViewById(R.id.rb_opt2_2);
    que2 = opt2RadioButton.isChecked();

    if(opt2RadioButton.isChecked()){

        myScore = myScore + 1;
        Toast.makeText(this, "Right!", Toast.LENGTH_SHORT).show();

    } else {
        Toast.makeText(this, "Wrong!", Toast.LENGTH_SHORT).show();
    }
}

public void questionThree(View view){
    RadioButton opt2RadioButton = (RadioButton) findViewById(R.id.rb_opt2_3);
    que3 = opt2RadioButton.isChecked();

    if(opt2RadioButton.isChecked()){

        myScore = myScore + 1;
        Toast.makeText(this, "Right!", Toast.LENGTH_SHORT).show();

    } else {
        Toast.makeText(this, "Wrong!", Toast.LENGTH_SHORT).show();
    }
}

}

Please help me to solve this issue

Thank You