TypeError: Error #1009 for Card Game [as3]

//--------IMPORT AWAY 3D-------//
import away3d.cameras.*;
import away3d.containers.*;
import away3d.materials.*;
import away3d.primitives.Plane;
import away3d.containers.ObjectContainer3D;
import away3d.core.math.Number3D;
 
//------IMPORT TWEENERS-------//
import caurina.transitions.*;
import flash.display.InteractiveObject;
import flash.display.Bitmap;
import flashx.textLayout.conversion.PlainTextExporter;
import flash.display.BitmapData;
import flash.events.Event;
import flash.utils.Timer;
import flash.events.TimerEvent;
 
//-------SET UP VARIABLES------//
//variable for the scene
var scene:Scene3D;
//variable for camera - angle
var camera:Camera3D;
//variable for view
var view:View3D;
//number of cards that you want to have
var totalchildren:int = 10;
//set up array to hold the cards
var cards:Array;
//array to hold the front of the cards
var textures:Array = [new texture0(0,0),
                 new texture1(0,0),
                 new texture2(0,0),
                 new texture3(0,0),
                 new texture4(0,0)];
//get the back of the cards
var backtexture:BitmapData = new CardBack(0,0);
//set width and height
var cardwidth:Number = 150;
var cardheight:Number = 205;
//distance between each card
var xoffset:Number = 10;
var yoffset:Number = 10;
//create an object to hold all the cards
var cardsholder:ObjectContainer3D;
//create the sides of the selected card
var selectedCard1:Plane;
var selectedCard2:Plane;
//disable mouse events - gives us control over every card
var disableMouseEvents:Boolean = false;
 
 
 
 
 
 
//------------FUNCTIONS-------------//
 
//----------Establish Scene/Viewing Area---------//
function initAway3D():void{
   var scene = new Scene3D;
   var camera = new Camera3D;
   //position the camera
   camera.y = 1000; //works like a zoom
   camera.z = 0;
   camera.lookAt(new Number3D(0,0,0));
   //create and position the view
   var view = new View3D({scene:scene, camera:camera});
   //put the view on the stage
   view.x = stage.stageWidth/2;
   view.y = stage.stageHeight/2;
   addChild(view);
}
 
//-----Create One of the Carfds------//
function createCard(texture:BitmapData, id:int):ObjectContainer3D{
   var card:ObjectContainer3D = new ObjectContainer3D();
   //var for the front
   var front:Plane = new Plane({width:cardwidth, height:cardheight, material:new BitmapMaterial(texture,{smmoth:true})});
   //var for the back
   var back:Plane = new Plane({width:cardwidth, height:cardheight, material:new BitmapMaterial(backtexture,{smmoth:true})});
   //positioning
   front.rotationY = 180;
   back.rotationZ = 180;
   back.rotationY = 180;
   
   //access id - use to determine the matches
   back.extra = {};
   back.extra.id = id;
   back.extra. targetCard = card;
   back.addOnMouseDown(onBackClicked);
   
   //spin moves
   card.rotationZ = 180;
   card.addChild(front);
   card.addChild(back);
   card.ownCanvas = true;
   
   //create the card
   return card;
 
}
 
 
//--------Create the rest of the cards----------//
function allCards():void{
   var cards = new Array();
   //(starts at 0, goes until it reaches the end of array, increases by 1)
   for(var i:int=0; i<textures.length; i++){
      //create the first card
      var card1:ObjectContainer3D = createCard(textures[i],i);
      //create it's match
      var card2:ObjectContainer3D = createCard(textures[i],i);
      //create it's match
      //var card3:ObjectContainer3D = create Card(textures[i],i);
      //create it's match
      //var card4:ObjectContainer3D = create Card(textures[i],i);
      cards.push(card1);
      cards.push(card2);
   }
}
 
//-------- SHUFFLE/RANDOMIZE CARDS---------//
function randomizeCards():void{
   //var to hold random order of cards
   var newArray:Array = new Array();
   while(cards.length>0){
      newArray.push(cards.splice(Math.floor(Math.random()*cards.length),1)[0]);
   }
   cards = newArray;
}
 
//-------Add Cards to the Scene-------//
function addCardsToScene():void{
   //var that holds everything
   var cardsholder = new ObjectContainer3D();
   //how many cards we currently have
   var cardNumber:int = 0;
   //create the grid
   //vertical part of the grid - number of rows
   for(var i:int = 0; i<2; i++){
      //number of columns
      for(var b:int = 0; b<5; b++){
         cards[cardNumber].x = b*(cardwidth+xoffset)+cardwidth/2;
         cards[cardNumber].z = i*(cardheight+yoffset)+cardheight/2;
         cardsholder.addChild(cards[cardNumber]);
         cardNumber++;
      }
   }
   var cardswidth:Number = (5*cardwidth) + (4*xoffset);
   var cardsheight:Number = (2*cardheight) + (1*yoffset);
   
   //position
   cardsholder.x = cardswidth/2;
   cardsholder.y = cardsheight/2;
   
   //add to the scene
   scene.addChild(cardsholder);
}
 
//-------------------CLICK FUNCTIONS-----------------//
function onBackClicked(event:Event):void{
   if(disableMouseEvents==false){
      if(selectedCard1==null){
         selectedCard1 = event.currentTarget as Plane;
      }
      else{
         if(selectedCard2==null){
            selectedCard2=event.currentTarget as Plane;
            waitForDecision();
            disableMouseEvents=true;
         }
      }
      Tweener.addTween(event.currentTarget.extra.targetCard,{y:50, rotationZ:0, time:1});
   }
}
 
//---------DEFINE THE DECISION-----------//
function waitForDecision():void{
   var timer:Timer = new Timer(1000, 1);
   timer.addEventListener(TimerEvent.TIMER, makeDecision);
   timer.start();
}
 
//----------WHAT TO DO IF RIGHT OR WRONG-----------//
function makeDecision(event:Event):void{
   //if it matches = right
   if(selectedCard1.extra.id == selectedCard2.extra.id){
      Tweener.addTween(selectedCard1.extra.targetCard,{alpha:0, time:0.3, onComplete:removeCard, onCompleteParams:[selectedCard1.extra.targetCard]});
      Tweener.addTween(selectedCard2.extra.targetCard,{alpha:0, time:0.3, onComplete:removeCard, onCompleteParams:[selectedCard1.extra.targetCard]});
 
   }
   //if its wrong
   else{
      Tweener.addTween(selectedCard1.extra.targetCard,{y:0, rotationZ:180, time:1});
      Tweener.addTween(selectedCard2.extra.targetCard,{y:0, rotationZ:180, time:1});
   }
   //reset variables for mouse clicks, and card slection
   disableMouseEvents = false;
   selectedCard1=null;
   selectedCard2=null;
}
 
//-------DEFINE REMOVE CARD FUNCTION----------//
function removeCard(event:ObjectContainer3D):void{
   cardsholder.removeChild(event);
   totalchildren--;
   if(totalchildren==0){
      trace("WIN");
   }
}
 
//---------------RENDER EVERYTHING-------------//
function startToRender():void{
   addEventListener(Event.ENTER_FRAME, render);
}
 
function render(event:Event):void{
   view.render();
}
 
//------------CALL ALL THE FUNCTIONS---------//
initAway3D();
allCards();
randomizeCards();
addCardsToScene();
startToRender();