android:uiOptions="splitActionBarWhenNarrow"

 <!-- the theme applied to the application or activity -->
    <style name="CustomActivityTheme" parent="@style/Theme.Base.AppCompat">
        <item name="android:actionBarStyle">@style/MyActionBar</item>   
        <!-- 自定义actionbar的背景颜色-->
        <item name="android:actionOverflowButtonStyle">@style/MyActionButtonOverflow</item>   
        <!--自定义actionbar的overflow图片-->
        <item name="android:actionBarDivider">@color/black</item>     
        <!-- 自定义actionbar的item之间的分割线-->
        <item name="android:popupMenuStyle">@style/MyPopupMenu</item>
        <!-- 自定义popupwindow的背景颜色-->
        <!-- other activity and action bar styles here -->
    </style>

    <!-- style for the action bar backgrounds -->
    <style name="MyActionBar" parent="@android:style/Widget.Holo.ActionBar">
        <item name="android:background">@color/black</item>
        <item name="android:backgroundStacked">@color/black</item>
        <item name="android:backgroundSplit">@color/black</item>
    </style>

 <style name="MyActionButtonOverflow" parent="android:style/Widget.Holo.Light.ActionButton.Overflow">
       <item name="android:src">@drawable/ic_dxhome_airplane_on</item>
       <item name="android:background">?android:attr/actionBarItemBackground</item>
       <item name="android:contentDescription">"Lala"</item>
   </style>

<style name="MyPopupMenu" parent="android:style/Widget.Holo.Light.ListPopupWindow">
       <item name="android:background">@color/white</item> 
</style>