Style bottom Line in Android

<?xml version="1.0" encoding="utf-8"?>
<layer-list xmlns:android="http://schemas.android.com/apk/res/android">
    <item
        android:top="-6dp"
        android:left="-6dp"
        android:right="-6dp"
        android:bottom="0dp">

        <shape android:shape="rectangle">
            <solid android:color="#88FFFF00"/>
            <stroke
                android:width="5dp"
                android:color="#FF000000"/>
        </shape>
    </item>
</layer-list>

It's kind of a hack, but I think this is probably the best way to do it. The dashed line will always be on the bottom, regardless of the height.

<layer-list xmlns:android="http://schemas.android.com/apk/res/android">

    <item>
        <shape android:shape="rectangle" >
            <solid android:color="#1bd4f6" />
        </shape>
    </item>

    <item android:top="-2dp" android:right="-2dp" android:left="-2dp">
        <shape>
            <solid android:color="@android:color/transparent" />
            <stroke
                android:dashGap="10px"
                android:dashWidth="10px"
                android:width="1dp"
                android:color="#ababb2" />
        </shape>
    </item>

</layer-list>

Explanation:

The second shape is transparent rectangle with a dashed outline. The key in making the border only appear along the bottom lies in the negative margins set the other sides. These negative margins "push" the dashed line outside the drawn area on those sides, leaving only the line along the bottom. One potential side-effect (which I haven't tried) is that, for views that draw outside their own bounds, the negative-margin borders may become visible.

This does the trick...

<item >
    <shape android:shape="rectangle">
        <solid android:color="#YOUR_BOTTOM_LINE_COLOR"/>
    </shape>
</item>

<item android:bottom="1.5dp">
    <shape android:shape="rectangle">
        <solid android:color="#YOUR_BG_COLOR"/>
    </shape>
</item>