Android ActionBar夏洛克去除白色区域

如何删除此白色背景？它只出现在平板电脑上

谢谢你抽出时间

<resources xmlns:android="http://schemas.android.com/apk/res/android">

    <style name="AppBaseTheme" parent="android:Theme.Light"></style>
    <style name="AppTheme" parent="AppBaseTheme"></style>

    <style name="MyTheme" parent="Theme.Sherlock.Light">
        <item name="actionBarStyle">@style/Widget.Styled.ActionBar</item>
        <item name="android:actionBarStyle">@style/Widget.Styled.ActionBar</item>
        <item name="android:actionModeBackground">@drawable/bg_actionbar</item>
        <item name="actionModeBackground">@drawable/bg_actionbar</item>
        <item name="actionModeCloseDrawable">@drawable/abs__ic_cab_done_holo_dark</item>
        <item name="android:windowContentOverlay">@null</item>
        <!--<item name="android:homeAsUpIndicator">@drawable/icon_actionbar_back</item>-->
    </style>

    <style name="Widget.Styled.ActionBar" parent="Widget.Sherlock.Light.ActionBar.Solid.Inverse">
        <item name="background">@drawable/bg_actionbar</item>
        <item name="android:background">@drawable/bg_actionbar</item>
    </style>

</resources>