title: Implement Navigation Drawer Activity to existing app
body: <p>I made a simple app which when I open it I see the wallpaper and the 2 buttons.First button opens my gallery and the second one opens a Calculator app. Now I want to be able to slide from left to right and bring up the Navigation Drawer Activity.
  I did this: right clicked on my app -> New -> Activity -> Navigation Drawer Activity. It created 2 java classes ( <code>NavigationActivity</code> and <code>NavigationDrawerFragment</code> ), some layouts (<code>activity_navigation</code> <code>fragment_navigation</code> and <code>fragment_navigation_drawer</code>). Anyway, what I don't know is how to make the navigation drawer show up, how do I link it to my <code>activity_main</code> ?</p>
  
  <p>This is the activity_main.xml:</p>
  
  <pre><code> &lt;RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
      xmlns:tools="http://schemas.android.com/tools"
      android:layout_width="fill_parent"
      android:layout_height="fill_parent"
      android:paddingLeft="@dimen/activity_horizontal_margin"
      android:paddingRight="@dimen/activity_horizontal_margin"
      android:paddingTop="@dimen/activity_vertical_margin"
      android:paddingBottom="@dimen/activity_vertical_margin"
      tools:context=".MainActivity"
      android:background="@drawable/digital_blue_wallp"&gt;
  
      &lt;TextView
          android:text="@string/welcome"
          android:layout_width="wrap_content"
          android:layout_height="wrap_content"
          android:textColor="#fff8fdff"
          android:textSize="24sp"
          android:id="@+id/welcome"
          android:layout_centerHorizontal="true"/&gt;
  
  
      &lt;Button
          android:layout_width="wrap_content"
          android:layout_height="wrap_content"
          android:id="@+id/button"
          android:background="@drawable/calcu"
          android:layout_alignParentBottom="true"
          android:layout_alignRight="@+id/welcome"
          android:layout_alignEnd="@+id/welcome"
          android:layout_centerHorizontal="true"/&gt;
  
      &lt;Button
          android:layout_width="wrap_content"
          android:layout_height="wrap_content"
          android:id="@+id/button2"
          android:background="@drawable/gallery"
          android:layout_alignParentBottom="true"
          android:layout_alignParentLeft="true"
          android:layout_alignParentStart="true" /&gt;
  
  
  &lt;/RelativeLayout&gt;
  </code></pre>