Question: I want to make a drawable for my Android button, defined as drawable. I found I could set all the borders by using a rectangle, but I got kinda stuck when I wanted it on three sides. I want for example have either the top or the bottom open. 

Could anyone show me how to do this?

Answer: 
If anyone is running into issues regarding padding taking effect in the accepted answer, try taking a look at: <https://stackoverflow.com/a/11006931>. That solution uses position attributes on the tags to achieve the same effect.

I was having trouble using the accepted answer here while creating drawables for use in an ActionBar, and the linked approach worked for me.
This might help you.

I The border on Three sides of the XML

```
<?xml version="1.0" encoding="utf-8"?>
<layer-list xmlns:android="http://schemas.android.com/apk/res/android">
    <item android:left="0dp" android:right="0dp" android:top="0dp" android:bottom="-5dp">
        <shape android:shape="rectangle">
            <solid android:color="#ffffff" />

            <corners android:radius="0dp" />
            <stroke android:width="3dp" android:color="#000000" />
        </shape>
    </item>
</layer-list>

```