zumo_2.0_android/app/src/main/res/layout/circle_animation.xml

<?xml version="1.0" encoding="utf-8"?>
<merge
  xmlns:android="http://schemas.android.com/apk/res/android"
  xmlns:tools="http://schemas.android.com/tools"
  android:layout_width="wrap_content"
  android:layout_height="wrap_content">

  <View
    android:id="@+id/loading_circle"
    android:layout_width="8dp"
    android:layout_height="8dp"
    android:background="@drawable/loading_circle"
    />
</merge>