how to show border only top and bottom

how to show border only top and bottom

this is my xml code below which is work fine only problem is is show
border on all four side i want only show border on top and bottom only
help me what do i do?
<?xml version="1.0" encoding="UTF-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android" >
<solid android:color="#FFFFFF" />
<stroke
android:width="3dip"
android:color="#B1BCBE" />
<padding
android:bottom="0dip"
android:left="0dip"
android:right="0dip"
android:top="0dip" />
</shape>