title: Add items to popup programmatically
body: <p>I need to create and add some items to a popup code-behind. It's easy to do this in XAML:</p>
  
  <pre><code>&lt;Popup StaysOpen="False"&gt;
      &lt;DockPanel&gt;
          //Items here
      &lt;/DockPanel&gt;
   &lt;/Popup&gt;
  </code></pre>
  
  <p>I think "Child" is where I need to add my items but I don't see any "Add", "Items", "Source" or "Content" inside. Does anyone know how to do this?</p>
  
  <pre><code>Popup myPopup= new Popup();
  myPopup.Child // ... need to add items there
  </code></pre>