Transparent circle with border
use this it will work
<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
android:shape="oval" >
<gradient
android:centerX=".6"
android:centerY=".40"
android:endColor="@android:color/transparent"
android:gradientRadius="20"
android:startColor="@android:color/transparent"
android:type="radial" />
<stroke
android:width="1dp"
android:color="#FFFFFF" />
<size
android:height="100dp"
android:width="100dp" />
</shape>
The stroke effect can be achieved drawing a transparent oval with the stroke of a required color (#000 in the example):
<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
android:shape="oval">
<solid android:color="@android:color/transparent" />
<stroke
android:width="1dp"
android:color="#000" />
<size
android:width="40dp"
android:height="40dp" />
</shape>
Hollow
<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
android:shape="oval">
<stroke
android:width="1dp"
android:color="@color/indicator_unselected" />
</shape>
Full
<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
android:shape="oval">
<corners android:radius="100dp" />
<solid android:color="@android:color/white" />
</shape>
Try something like this
<shape xmlns:android="http://schemas.android.com/apk/res/android"
android:innerRadius="0dp"
android:shape="ring"
android:thicknessRatio="2"
android:useLevel="false" >
<solid android:color="@android:color/transparent" />
<stroke
android:width="2dp"
android:color="@android:color/darker_gray" />
</shape>
Update: made android:thicknessRatio="2"
to give full circle (using Nexus 5 - Lollipop)