styles.xml

<?xml version="1.0" encoding="utf-8"?>
<resources>

    <style name="LaunchTheme" parent="Theme.AppCompat.Light.NoActionBar">
        <item name="android:windowBackground">@drawable/launch_background</item>
    </style>

    <style name="NormalTheme" parent="Theme.AppCompat.Light.NoActionBar">
        <item name="android:windowBackground">?android:colorBackground</item>
    </style>
</resources>