title: How to show/hide submenus inside NavigationView android
body: <p>I want to create an expandablelistview like view inside navigation drawer where initially only main titles are shown (collapsed submenus). When title is clicked the submenus should appear (if possible animate)</p>
  
  <p>I am using android.support.design.widget.NavigationView. I am able to add submenus via xml.</p>
  
  <pre><code> &lt;group android:checkableBehavior="all"&gt;
      &lt;item
          android:id="@+id/action_venues"
          android:title="TITLE 1"&gt;
          &lt;menu&gt;
              &lt;group
                  android:id="@+id/group1"
                  android:checkableBehavior="single"
                  &gt;
                  &lt;item android:title="SUBTITLE1.1" /&gt;
                  &lt;item android:title="SUBTITLE1.2" /&gt;
                  &lt;item android:title="SUBTITLE1.3" /&gt;
  
              &lt;/group&gt;
          &lt;/menu&gt;
      &lt;/item&gt;
      &lt;item
          android:id="@+id/action_vendors"
          android:title="TITLE2"&gt;
          &lt;menu&gt;
              &lt;group
                  android:id="@+id/group2"
                  android:checkableBehavior="single"
                  android:visible="false"&gt;
                  &lt;item android:title="SUBTITLE2.1" /&gt;
                  &lt;item android:title="SUBTITLE2.2" /&gt;
                  &lt;item android:title="SUBTITLE2.3" /&gt;
  
              &lt;/group&gt;
          &lt;/menu&gt;
      &lt;/item&gt;
  </code></pre>
  
  <p></p>
  
  <p>But if I keep any group in the xml android:visible="false" it doesn't appear in the drawer.</p>
  
  <p>I also tried programatically showing/hiding the submenu with:</p>
  
  <pre><code>subMenu1.setGroupVisible(R.id.group1,false);
  </code></pre>
  
  <p>But it just hides the title menu also.</p>
  
  <p>Is it possible with android.support.design.widget.NavigationView or do I have to use a custom view?</p>