<?xml version="1.0" encoding="utf-8"?>

<animation-list
xmlns:android="http://schemas.android.com/apk/res/android"
android:oneshot="false" >
<item android:drawable="@drawable/ic_loading_msgsend_01" android:duration="300"></item>
<item android:drawable="@drawable/ic_loading_msgsend_02" android:duration="300"></item>
<item android:drawable="@drawable/ic_loading_msgsend_03" android:duration="300"></item>
</animation-list>

使用

<ImageView android:id="@+id/iv_load_plus" android:layout_width="20dp" android:layout_height="10dp" android:src="@drawable/ic_loading_msgplus_anim" android:layout_centerInParent="true" />