title: addChild(): How can I know when a DisplayObject is actually displayed on the stage?
body: <p>I've got a large (4096x4096) image loaded into memory, but when I try to use addChild, there is a long delay before it actually gets drawn to the screen.  This is expected.  However, is there an event I can listen for to know the moment that the DisplayObject (a .png image) is actually drawn to the screen?</p>
  
  <p>I am trying to load the images onto the screen, then do something after they are actually drawn.</p>