android - 在 AppTheme 中设置 windowBackground 导致背景在 3-5 秒后消失并变为黑屏

Question

我有一个AppTheme我在这里指定的：

<resources>

<!--
    Base application theme, dependent on API level. This theme is replaced
    by AppBaseTheme from res/values-vXX/styles.xml on newer devices.
-->
<style name="AppBaseTheme" parent="Theme.AppCompat.Light">
    <!--
        Theme customizations available in newer API levels can go in
        res/values-vXX/styles.xml, while customizations related to
        backward-compatibility can go here.
    -->
</style>

<!-- Application theme. -->
<style name="AppTheme" parent="AppBaseTheme">
    <!-- All customizations that are NOT specific to a particular API-level can go here. -->
       <item name="android:windowBackground">@drawable/wallpaper2</item>
</style>

以及我在我的清单中将它设置为我的各种Activities.

但是，当应用程序启动时，它会显示背景，也许一秒钟？- 然后立即将其重置为黑色...

显现：

    <?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.nanospark.cnc"
    android:versionCode="1"
    android:versionName="1.0" >

    <uses-sdk
        android:minSdkVersion="11"
        android:targetSdkVersion="19" />

    <application
        android:name=".CustomIOIO"
        android:allowBackup="true"
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >
        <activity
            android:name=".MainActivity"
            android:label="@string/app_name"
            android:theme="@style/AppTheme" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
        <activity
            android:name=".ProfileCreateActivity"
            android:label="@string/profilecreationpageheader" >
        </activity>
        <activity
            android:name=".ContactCreateActivity"
            android:label="@string/contactcreationpageheader">
        </activity>
        <activity
            android:name=".EventCreateActivity"
            android:label="@string/eventcreationpageheader">
        </activity>

    </application>

</manifest>