title: Xamarin Forms: Open menu by custom button in MasterDetail based project
body: <p>In my  MasterDetail based  project, I need a custom appearence for the navigation part for a specific detail page. To avoid rendering a custom Navigation, I set </p>
  
  <pre><code>    NavigationPage.SetHasNavigationBar(this, false);
  </code></pre>
  
  <p>so navigation disappear an then I create by grid a  background and a button like:</p>
  
  <pre><code>&lt;Grid&gt;
     &lt;Image Source="BackgroundImage.png"/&gt; &lt;!-- This should fill the grid --&gt;
     &lt;Image Source="back_button" HorizontalOptions="StartAndExpand" Aspect="AspectFit" &gt;
        &lt;Image.GestureRecognizers&gt;
          &lt;TapGestureRecognizer Tapped="Handle_Tapped"/&gt;
        &lt;/Image.GestureRecognizers&gt;
      &lt;/Image&gt;
  &lt;/Grid&gt;
  </code></pre>
  
  <p>Handle_Tapped should be manage the open/hide menu of master detail. I think i need to manage the IsPresented properties like</p>
  
  <pre><code>    MasterDetailPage nav = new MasterDetailPage();
      nav.IsPresented = true;
  </code></pre>
  
  <p>but that do nothing. Any help? </p>