I recently implemented a navigation drawer into the main screen of my app. For some reason a small grey (or transparent black) bar is being rendered on top of it.  

Screenshot:

[![Screenshot](https://i.stack.imgur.com/nUt27.png)](https://i.stack.imgur.com/nUt27.png)

Layout code:

```
<android.support.design.widget.CoordinatorLayout 
... >

    <LinearLayout
        ... >

        <android.support.design.widget.AppBarLayout
            android:id="@+id/appbar"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:paddingTop="@dimen/appbar_padding_top"
            android:theme="@style/AppBarOverlay">

            <android.support.v7.widget.Toolbar
                android:id="@+id/toolbar"
                android:layout_width="match_parent"
                android:layout_height="?attr/actionBarSize"
                android:background="?attr/colorPrimary"
                app:layout_scrollFlags="scroll|enterAlways"
                app:popupTheme="@style/PopupOverlay"/>

        </android.support.design.widget.AppBarLayout>

        <android.support.v4.widget.DrawerLayout
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:id="@+id/drawer_layout">

            <fragment
                ... />

            <android.support.design.widget.NavigationView
                android:layout_width="wrap_content"
                android:layout_height="match_parent"
                android:id="@+id/navigation"
                android:layout_gravity="start">

                <ListView
                    android:layout_width="match_parent"
                    android:layout_height="match_parent"
                    android:id="@+id/list_nav"/>

            </android.support.design.widget.NavigationView>

        </android.support.v4.widget.DrawerLayout>

    </LinearLayout>

    <android.support.design.widget.FloatingActionButton
        ... />

</android.support.design.widget.CoordinatorLayout>

```

The Java portion is just your generic list-filling stuff. Let me know if you need more code.

How can I remove this weird bar?