SLAM/mobile/src/main/res/layout/activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
    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:orientation="vertical">

    <include layout="@layout/toolbar_main" />

    <android.support.v4.widget.DrawerLayout
        android:id="@+id/drawer_layout"
        android:orientation="vertical"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        tools:openDrawer="start">

        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:orientation="vertical">

            <include layout="@layout/item_chatmessage" />
            <include layout="@layout/chatlist_singlechat" />

        </LinearLayout>

        <android.support.design.widget.NavigationView
            android:id="@+id/navigation_view"
            android:layout_width="wrap_content"
            android:layout_height="match_parent"
            android:layout_gravity="start"
            android:background="?attr/colorBackground"
            app:menu="@menu/drawer_main" />

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