activity_chat.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout 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:background="#ededed"
    tools:context=".ChatActivity">

    <include
        android:id="@+id/chat_app_bar"
        layout="@layout/app_bar_layout"
        android:layout_width="match_parent"
        android:layout_height="wrap_content" />

    <android.support.v4.widget.SwipeRefreshLayout
        android:id="@+id/message_swipe_layout"
        android:layout_width="wrap_content"
        android:layout_height="match_parent"
        android:layout_above="@+id/linearLayout"
        android:layout_alignParentStart="true"
        android:layout_below="@+id/chat_app_bar">

        <android.support.v7.widget.RecyclerView
            android:id="@+id/messages_list"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:layout_alignParentStart="true"
            android:layout_alignParentTop="true">

        </android.support.v7.widget.RecyclerView>

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

    <LinearLayout
        android:id="@+id/linearLayout"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_alignParentBottom="true"
        android:layout_alignParentStart="true"
        android:background="@color/colorPrimary"
        android:orientation="horizontal"
        android:weightSum="10">

        <ImageButton
            android:id="@+id/chat_add_btn"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_alignParentBottom="true"
            android:layout_alignParentEnd="true"
            android:layout_weight="1"
            android:background="@color/colorWhite"
            android:paddingBottom="10dp"
            android:paddingLeft="5dp"
            android:paddingRight="5dp"
            android:paddingTop="17dp"
            app:srcCompat="@drawable/add" />

        <EditText
            android:id="@+id/chat_message_view"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_weight="8"
            android:background="@color/colorWhite"
            android:ems="10"
            android:hint="Message"
            android:inputType="text|textCapSentences"
            android:paddingBottom="12dp"
            android:paddingLeft="5dp"
            android:paddingRight="5dp"
            android:paddingTop="14dp" />

        <ImageButton
            android:id="@+id/chat_send_btn"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_alignParentBottom="true"
            android:layout_alignParentEnd="true"
            android:layout_weight="1"
            android:background="@color/colorWhite"
            android:paddingBottom="6dp"
            android:paddingLeft="5dp"
            android:paddingRight="5dp"
            android:paddingTop="11dp"
            app:srcCompat="@drawable/colibri_bird" />

    </LinearLayout>

    <View
        android:layout_width="match_parent"
        android:layout_height="1dp"
        android:layout_alignParentStart="true"
        android:layout_below="@+id/chat_app_bar"
        android:background="@drawable/toolbar_dropshadow" />


</RelativeLayout>