Transaparent black gradient shape drawable color code

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android">
    <gradient 
        android:startColor="#000"
        android:centerColor="#00000000"
        android:endColor="#000"
        android:angle="270"
        android:dither="true"
     />
</shape>

This is the code i tried.But it ends up as pure black