center tabs

src/main/res/layout/file_details_fragment.xml

@@ -198,7 +198,7 @@
             android:layout_width="match_parent"
             android:layout_height="wrap_content"
             app:tabGravity="center"
-            app:tabMode="scrollable"
+            app:tabMode="fixed"
             android:background="@color/white" />
 
         <android.support.v4.view.ViewPager