SetActivityAttribute(Main, android:theme, @style/CustomActTheme)
CreateResource(values, theme.xml,
<resources>
<style name="CustomActTheme">
<item name="android:windowBackground">@android:color/transparent</item>
<item name="android:windowNoTitle">true</item>
<item name="android:windowFullscreen">false</item>
</style>
</resources>
)