Customize Android ActionBar overflow icon.

styles.xml

<resources>

    <!-- Base application theme. -->
    <style name="AppTheme" parent="android:Theme.Holo.Light">
        <item name="android:actionBarStyle">@style/ActionBar</item>
        <item name="android:actionOverflowButtonStyle">@style/ActionBarOverflowButton</item>
    </style>

    <!-- ActionBar theme  -->
    <style name="ActionBar" parent="@android:style/Widget.Holo.Light.ActionBar.Solid.Inverse">
        <item name="android:background">@android:color/holo_blue_dark</item>
    </style>

    <!-- ActionBar Overflow Button -->
    <style name="ActionBarOverflowButton" parent="@android:style/Widget.Holo.ActionButton.Overflow">
        <item name="android:src">@drawable/ic_action_overflow</item>
    </style>

</resources>