app/src/main/res/values/styles.xml
<resources>
<style name="Widget.Theme.MyApplication.ActionBar.Fullscreen" parent="Widget.AppCompat.ActionBar">
<item name="android:background">@color/black_overlay</item>
</style>
<style name="Widget.Theme.MyApplication.ButtonBar.Fullscreen" parent="">
<item name="android:background">@color/black_overlay</item>
<item name="android:buttonBarStyle">?android:attr/buttonBarStyle</item>
</style>
</resources>