This code worked:
<?xml version="1.0" encoding="utf-8"?>
<layer-list xmlns:android="http://schemas.android.com/apk/res/android" >
<item
android:bottom="-10dp"
android:left="-10dp"
android:top="-10dp">
<shape android:shape="rectangle" >
<solid android:color="@android:color/transparent" />
<stroke
android:width="3dp"
android:color="#ff000000" />
</shape>
</item>
</layer-list>