将popupMenu样式添加到AppTheme：

Add popupMenu style to ur AppTheme:

<style name="AppTheme" parent="android:Theme.Light">
    <item name="android:popupMenuStyle">@style/PopupMenu</item>
</style>

<style name="PopupMenu" parent="@android:style/Widget.PopupMenu">
    <item name="android:popupBackground">@android:color/white</item>
</style>

manifest.xml：

manifest.xml:

 <application
    android:allowBackup="true"
    android:icon="@drawable/ic_launcher"
    android:label="@string/app_name"
    android:theme="@style/AppTheme" >
.............
</application>