title: Add child to parent component that is not visible in flex
body: <p>I have a mxml file that extends a parent class. The parent has a component that is hidden initially and only shown once a button is pressed. I would like to add a new child component to this hidden component from my extended mxml. Is there a way to access the super component and add the child once the buton is pressed? Maybe listen to an event?</p>
  
  <p>Right now i have a solution that solves the problem by loading the hidden components but it´s not a nice solution.</p>
  
  <pre><code>super.advancedOptionsSearchBox.getChildren();
  super.advancedOptionsSearchBox.addChildAt(getEANContainer(), 1);
  </code></pre>
  
  <p>If i do not call the getChildren I get a index out of bounds exception on the call to addChildAt method since the array of children is empty in the hidden component.</p>