Make app with translucent background

To make your app with translucent background, apply the following code in your theme.

<item name="android:windowIsTranslucent">true</item>
<item name="android:windowBackground">@android:color/transparent</item>

For example, modify /res/values/styles.xml (the auto-generated style):
<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="android:Theme.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:windowIsTranslucent">true</item>
     <item name="android:windowBackground">@android:color/transparent</item>
        
    </style>

</resources>

Translucent background