title: Put the button on the bottom center of the screen with the RecyclerView
body: <p>I have RecyclerView and Button. Button is coming under the recyclerView. I want to put the button to the bottom center of the screen in my screen. That should not change in any device. Because in some devices button get disappear.</p>
  
  <p>My Xml.</p>
  
  <pre><code>&lt;?xml version="1.0" encoding="utf-8"?&gt;
  &lt;LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
      android:layout_width="match_parent"
      android:layout_height="match_parent"
      android:background="#33DADADA"
      android:fitsSystemWindows="true"
      android:gravity="center_horizontal"
      android:orientation="vertical"&gt;
  
      &lt;include
          android:id="@+id/app_bar"
          layout="@layout/app_toolbar"&gt;&lt;/include&gt;
  
      &lt;LinearLayout
          android:layout_width="match_parent"
          android:layout_height="wrap_content"
          android:layout_gravity="center"
          android:background="#4dabf5"
          android:gravity="center"
          android:orientation="horizontal"&gt;
  
          &lt;TextView
              android:layout_width="wrap_content"
              android:layout_height="wrap_content"
              android:text="Distribution  Channel  "
              android:textSize="18sp" /&gt;
  
          &lt;Spinner
              android:id="@+id/selectDistribChannel"
              android:layout_width="150dp"
              android:layout_height="wrap_content"&gt;&lt;/Spinner&gt;
  
      &lt;/LinearLayout&gt;
  
      &lt;AutoCompleteTextView
          android:id="@+id/autoCompleteTextView"
          android:layout_width="320dp"
          android:layout_height="35dp"
          android:layout_marginBottom="8dp"
          android:layout_marginTop="8dp"
          android:background="@drawable/rounded_edittext"
          android:focusable="true"
          android:focusableInTouchMode="true"
          android:gravity="center"
          android:hint="Search Products"
          android:singleLine="true" /&gt;
  
  
      &lt;android.support.v7.widget.RecyclerView
          android:id="@+id/selectedItemRecyclerView"
          android:layout_width="match_parent"
          android:layout_height="350dp"
          android:background="#33DADADA"
          android:padding="5dp"&gt;
  
      &lt;/android.support.v7.widget.RecyclerView&gt;
  
      &lt;LinearLayout
          android:layout_width="match_parent"
          android:layout_height="wrap_content"
          android:gravity="center|bottom"&gt;
  
          &lt;Button
              android:id="@+id/bAdd"
              android:layout_width="250dp"
              android:layout_height="48dp"
              android:text="Send"
              android:textColor="@color/btn_login" /&gt;
  
      &lt;/LinearLayout&gt;
  
  
  &lt;/LinearLayout&gt;
  </code></pre>