title: WPF canvas VisibilityChanged event
body: <p>I want to set up an event to run when the <code>Visibility</code> is changed on a WPF <code>Canvas</code> control.</p>
  <pre><code>canvas1.VisibleChanged += new EventHandler(canvas1_VisibleChanged);
  </code></pre>
  <p>I have tried the above but it doesn't work, anyone know how to do it ?</p>