title: Why isn't the animateActiveItem function animating in Sencha Touch
body: <p>I have the following code in my app class:</p>
  
  <pre><code> switchMainView: function (newView, config) {
          if (this.currentView != false) {
              Ext.Viewport.remove(this.currentView);
          }
  
          this.currentView = Ext.create(newView, config);        
          Ext.Viewport.animateActiveItem(this.currentView, { type: 'slide', direction: 'right' })
      },
  </code></pre>
  
  <p>Which can be called from any controller.  However, it is not showing the animation. Any ideas what is wrong with it?</p>