Android Question How to change background color for PopupMenu?

<?xml version="1.0" encoding="utf-8"?>


<resources>
<!--
    <color name="My_popupBackground_color">#ffffff</color>
-->
    <color name="My_popupBackground_color">@android:color/white</color>
    <style name="MyTheme" parent="android:style/Theme.Holo">
    <item name="android:popupBackground">@color/My_popupBackground_color</item>
    </style>
</resources>