black nav bar on image preview

Signed-off-by: tobiasKaminsky <tobias@kaminsky.me>

src/main/res/values-v27/styles.xml

@@ -44,4 +44,15 @@
         <item name="android:windowLightNavigationBar">false</item>
     </style>
 
+    <style name="Theme.ownCloud.Overlay" parent="Theme.ownCloud">
+        <item name="android:actionBarStyle">@style/Theme.ownCloud.Overlay.ActionBar</item>
+        <item name="android:windowActionBarOverlay">true</item>
+        <item name="android:windowFullscreen">true</item>
+        <item name="android:windowTranslucentStatus">true</item>
+        <!-- Support library compatibility -->
+        <item name="actionBarStyle">@style/Theme.ownCloud.Overlay.ActionBar</item>
+        <item name="windowActionBarOverlay">true</item>
+        <item name="android:navigationBarColor">@color/black</item>
+    </style>
+
 </resources>