Android Air App using AdMob "NULL Object" Error?!?

Question

Hi,
I am currently developing an app using adobe air flashbuilder and I have incorporated AdMob type html adverts into it. The Adverts do come up nicely however if I run the app in debug mode I get this error:
TypeError: Error #1009: Cannot access a property or method of a null object reference.
    at model::AdMob/createAd()[C:\Users\Jack\Documents\Dropbox\Projects\App\App Final\src\model\AdMob.as:37]
The Ads do still work regardless of this however this is then affecting other elements within the app so I would like to get rid of the error that is happening. Below is my code in the "AdMob.as" file where I believe the issue to be occuring, can someone please help me with this?
package model
    import flash.display.Stage;
    import flash.events.Event;
    import flash.events.LocationChangeEvent;
    import flash.events.MouseEvent;
    import flash.geom.Rectangle;
    import flash.media.StageWebView;
    import flash.net.URLRequest;
    import flash.net.navigateToURL;
    public class AdMob
        // setup variables
        private var _stageWebView:StageWebView;
        private var myAdvertURL:String = "http://www.test.co.uk/AdMob/test.html";
        //private var myAdvertURL:String;
        private var adWidth:Number=480;
        private var adHeight:Number=85;
        private var stage:Stage;
        public function AdMob(adURL:String,_stage:Stage)
            myAdvertURL=adURL;
            stage=_stage;
            createAd();
        public function createAd():void {
            // check that _stageWebView doersn't exist
            if (! _stageWebView) {
                _stageWebView = new StageWebView () ;
                // set the size of the html 'window'
                _stageWebView.viewPort = new Rectangle(0,stage.stageHeight-adHeight, 800, adHeight);
                //_stageWebView.viewPort = new Rectangle((stage.stageWidth-adWidth)/2,stage.stageHeight-adHeight,adWidth,adHeight);
                // add a listener for when the content of the StageWebView changes
                _stageWebView.addEventListener(LocationChangeEvent.LOCATION_CHANGE,onLocationChange);
                //add a listener for when the ad is loaded
                _stageWebView.addEventListener(Event.COMPLETE,onComplete);
                // start loading the URL;
                _stageWebView.loadURL(myAdvertURL);
            // show the ad by setting it's stage property;
            //showAd();
        public function destroyAd():void {
            // check that the instace of StageWebView exists
            if (_stageWebView) {
                trace("removing advert");
                // destroys the ad
                _stageWebView.stage = null;
                _stageWebView = null;
        public function toggleAd():void {
            trace("toggling advert",_stageWebView);
            // check that StageWebView instance exists
            if (_stageWebView) {
                trace("_stageWebView.stage:"+_stageWebView.stage);
                if (_stageWebView.stage == null) {
                    //show the ad by setting the stage parameter
                    _stageWebView.stage = stage;
                } else {
                    // hide the ad by nulling the stage parameter
                    _stageWebView.stage = null;
            } else {
                // ad StageWebView doesn't exist - show create it
                createAd();
        public function onLocationChange(event:LocationChangeEvent):void {
            // check that it's not our ad URL loading
            if (_stageWebView.location != myAdvertURL) {
                // destroy the ad as the user has kindly clicked on my ad
                destroyAd();
                // Launch a normal browser window with the captured  URL;
                navigateToURL( new URLRequest( event.location ) );
        public function onComplete(event:Event):void{
            //add the ad when it is loaded. If not it will apear a white rectangle until the load is complete.
            showAd();
        public function updateAd(adURL:String=null):void{
            if (adURL!=null){
                myAdvertURL = adURL;
            destroyAd();
            createAd();
        public function showAd():void{
            if (_stageWebView)
                _stageWebView.stage = stage;
        public function hideAd():void{
            if (_stageWebView)
                _stageWebView.stage = null;

Answer 1

@zhenya1919 - since you're currently going through this, could you please open a new bug report on this over at https://bugbase.adobe.com?  When adding the bug, please include some sample code or a sample application so we can quickly test this out internally.  If you'd like to keep this private, feel free to email the attachment to me directly ([email protected]). 
Once added, please post back with the URL so that others effected can add their comments and votes.
Thanks,
Chris