hcp-pad/home/src/main/res/drawable/anim_loading.xml

<?xml version="1.0" encoding="utf-8"?>
<animation-list xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:oneshot="false"
    tools:ignore="ResourceName">
    <item
        android:drawable="@mipmap/icon_dolphin_four"
        android:duration="280" />
    <item
        android:drawable="@mipmap/icon_dolphin_five"
        android:duration="280" />
    <item
        android:drawable="@mipmap/icon_dolphin_six"
        android:duration="280" />
    <item
        android:drawable="@mipmap/icon_dolphin_seven"
        android:duration="280" />
</animation-list>