Hang Calling function after Document Class' Event.ADDED

Question

I was trying to load an external SWF (that contains the below code in its document class) with the Loader class but i keep on receiving Error #1009: Cannot access a property or method of a null object reference. So i tried to use the event listener Event.ADDED in MyDocumentClass constructor of the external SWF to let the document class be part of the display list before i invoke createRandomGraph. But when i place createRandomGraph( ) inside onStageReady, The compilation process hangs. When i leave the createRandomGraph( ) inside the constructor, it works perfectly as stand alone but will produce Error 1009 if loaded within the loader SWF. Any ideas?
public function MyDocumentClass( )
    this.addEventListener(Event.ADDED, onStageReady);
    createRandomGraph( )
private function onStageReady(oEvent:Event):void
    this.removeEventListener(Event.ADDED, onStageReady);
private function createRandomGraph( ):void
    var cRandomGraph:RandomGraph = new RandomGraph();
    cRandomGraph.x = 10;
    cRandomGraph.y = stage.stageHeight - nH - 25;
    cRandomGraph.setDimensions(nW,nH);
    cRandomGraph.createGraphBackground();
    this.addChild(cRandomGraph);

Answer 1

use:
public function MyDocumentClass( )
    this.addEventListener(Event.ADDED_TO_STAGE, onStageReady);
private function onStageReady(oEvent:Event):void
    this.removeEventListener(Event.ADDED, onStageReady);
createRandomGraph();
private function createRandomGraph( ):void
    var cRandomGraph:RandomGraph = new RandomGraph();
    cRandomGraph.x = 10;
    cRandomGraph.y = stage.stageHeight - nH - 25;
    cRandomGraph.setDimensions(nW,nH);
    cRandomGraph.createGraphBackground();
    this.addChild(cRandomGraph);