res/values/themes.xml

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <!-- A custom theme for the LensPicker to enable animation when it is activated. -->
    <style name="Theme.FloatingLensPicker" parent="android:Theme.Material.Light.NoActionBar">
        <item name="android:windowBackground">@android:color/transparent</item>
        <item name="android:colorBackgroundCacheHint">@null</item>
        <item name="android:windowIsTranslucent">true</item>

        <item name="android:windowNoTitle">true</item>
        <item name="android:windowContentOverlay">@null</item>

        <item name="android:statusBarColor">@android:color/black</item>
        <item name="android:windowAnimationStyle">@android:style/Animation.Dialog</item>
    </style>
</resources>