<?xml version="1.0" encoding="utf-8"?>
<layer-list xmlns:android="http://schemas.android.com/apk/res/android">
<!-- 只有上下边框的shape -->
<item>
<shape>
<!-- 边框颜色 -->
<solid android:color="@color/color_d6d6d6"/>
</shape>
</item>
<!-- 想保留哪一边就设置哪一边边框就好了,列如只有上边框:top="1dp" -->
<item android:top="1dp" android:bottom="1dp">
<shape>
<solid android:color="@color/color_ffffff"/>
</shape>
</item>
</layer-list>