load_progress_animation.xml

<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android">
    <rotate
        android:duration="1500"
        android:fromDegrees="0"
        android:interpolator="@android:anim/linear_interpolator"
        android:pivotX="50%"
        android:pivotY="50%"
        android:repeatCount="-1"
        android:repeatMode="restart"
        android:startOffset="-1"
        android:toDegrees="+360" />
</set>