Estoy tratando de configurar el Navigation drawer detrás de la Toolbar de herramientas, ya intenté configurar android:layout_marginTop="@dimen/abc_action_bar_default_height_material" en NanvigationView pero nada cambió y también sigo este cajón de navegación debajo de la barra de herramientas pero no funciona

actividad_principal.xml:

 <?xml version="1.0" encoding="utf-8"?> <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools" xmlns:app="http://schemas.android.com/apk/res-auto" android:id="@+id/top_parent" android:layout_width="match_parent" android:layout_height="match_parent" android:fitsSystemWindows="true" tools:context=".MainActivity"> <include layout="@layout/app_bar_main" android:layout_width="match_parent" android:layout_height="match_parent" /> <android.support.v4.widget.DrawerLayout android:id="@+id/drawer_layout" android:layout_width="match_parent" android:layout_height="match_parent" android:fitsSystemWindows="true" tools:openDrawer="start"> <android.support.design.widget.NavigationView android:id="@+id/nav_view" android:layout_width="wrap_content" android:layout_height="match_parent" android:layout_gravity="start" android:fitsSystemWindows="false" android:theme="@style/NavigationView" android:background="#2b2b2b" app:itemTextColor="#FFF" app:menu="@menu/activity_main_drawer" /> </android.support.v4.widget.DrawerLayout> </RelativeLayout>

App_bar_principal.xml:

 <?xml version="1.0" encoding="utf-8"?> <android.support.design.widget.CoordinatorLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:app="http://schemas.android.com/apk/res-auto" xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent" android:layout_height="match_parent" android:fitsSystemWindows="true" tools:context="maa.a4kandhdwallpapers.MainActivity"> <android.support.design.widget.AppBarLayout android:layout_width="match_parent" android:layout_height="wrap_content" android:theme="@style/AppTheme.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:popupTheme="@style/AppTheme.PopupOverlay" /> </android.support.design.widget.AppBarLayout> <include layout="@layout/content_main" /> </android.support.design.widget.CoordinatorLayout>