loading_progress_bg.xml

<?xml version="1.0" encoding="UTF-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android" >

    <gradient
        android:angle="270.0"
        android:centerColor="#99000000"
        android:centerY="0.5"
        android:endColor="#99000000"
        android:startColor="#99000000" >
    </gradient>

    <corners android:radius="5dip" />

    <padding
        android:bottom="0dp"
        android:left="0dp"
        android:right="0dp"
        android:top="0dp" />

</shape>