android/app/src/main/res/drawable/orange_circle.xml

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
    android:shape="oval">
    <solid android:color="@color/action_orange" />
    <size
        android:width="@dimen/nav_question_num_circle_size"
        android:height="@dimen/nav_question_num_circle_size"/>
</shape>