Change View State Based On Screen Orientation?

Question

I'd like my app to change layouts based on the current screen orientation.  I believe this is done through view states.  I have three questions...
1) How do I check the current orientation?
2) Is there an event listener that will tell me when the orientation changes?
3) How do I toggle between view states?
Thank in advance!
UPDATE: I figured out the answer to question 3...
currentState = 'yourStateName';
UPDATE II: I figured out the answer to question 1 as well.  I simply used the Capabilities object to determine the screens current width & height, then compare the two.  All of this is in a function that gets called when the app launches:
public function checkOrientation():void
     var screenWidth:Number = Capabilities.screenResolutionX;
     var screenHeight:Number = Capabilities.screenResolutionY;
     if (screenWidth > screenHeight) {currentState='yourStateName1';}
     else if (screenWidth < screenHeight) {currentState='yourStateName2';}
Now all I have to do is figure out how to call this function when there is an orientation change.  I tried the code below but get the included error:
stage.addEventListener(Event.RESIZE, checkOrientation); // ERROR: Access of undefined property stage
Why can't access the "stage" property???

Answer 1

Hi,
I work on platform using flash bulider 4, later i finsh the platform but i meeting one problem is resize project to work with diffrent size screen, but i can't solve the problem, i need platform work with diffrent Screen Orientation without problem could some help  please, this that what i done in code please help.
Thanks,
<?xml version="1.0" encoding="utf-8"?>
<s:Application xmlns:fx="http://ns.adobe.com/mxml/2009"
               xmlns:s="library://ns.adobe.com/flex/spark"
               xmlns:mx="library://ns.adobe.com/flex/mx" xmlns:rtc="http://ns.adobe.com/rtc" width="100%" height="100%" backgroundColor="#51575D">
       <fx:Style source="Client.css"/>
         <fx:Script>
        <![CDATA[
            import mx.events.FlexEvent;
            import flash.events.FullScreenEvent;
            protected function txtUsername_enterHandler(event:FlexEvent):void
                // TODO Auto-generated method stub
                connectRoom.login();
                labelUsername.visible = false;
                txtUsername.visible = false;
            function fullScreenRedraw(event:FullScreenEvent):void
                if (event.fullScreen)
                    width  = Capabilities.screenResolutionX;
                    height = Capabilities.screenResolutionY;
                else
                    width = stage.stageWidth;
                    height = stage.stageHeight;
        ]]>
    </fx:Script>
       <fx:Declarations>
         <s:Move duration="500" id="moveEffect"/>
        <s:Resize duration="500" id="resizeEffect"/>
    </fx:Declarations>
              <mx:Image x="0" y="0" width="100%"  height="100%" scaleContent="false" autoLoad="true" source="greenbackground.png"/>
                                 <rtc:ConnectSessionContainer horizontalScrollPolicy="off" verticalScrollPolicy="off" id="connectRoom" autoLogin="false"
                                       roomURL="https://collaboration.adobelivecycle.com/account/yourroom"
                                       y="20" width="95%" height="90%" backgroundColor="#212D4B" contentBackgroundColor="#F6F6F0" borderAlpha="1.0" cornerRadius="30" contentBackgroundAlpha="1.0" backgroundAlpha="0.4" x="33" dropShadowVisible="true" borderVisible="true">
                    <rtc:authenticator>
                            <rtc:AdobeHSAuthenticator userName="{txtUsername.text}"/>
                 </rtc:authenticator>
                      <rtc:SimpleChat width="293" height="258" x="2" y="165" chromeColor="#384D91"/>
                       <rtc:WebcamSubscriber y="4" displayUserBars="true"  width="292" height="158" x="2"/>
                 <rtc:AudioSubscriber id="audioSub" width="0" height="0"/>
                                     <rtc:FileShare height="135" width="290" x="5" y="425" chromeColor="#284C79"/>
                    <rtc:ScreenShareSubscriber id="scrShare" width="81%" height="99%" y="4" x="299"/>
    </rtc:ConnectSessionContainer>
    <s:Label id="labelUsername" y="230" text="   Enter a username and press Enter:&#xd;" color="#B5C40D" fontWeight="bold" horizontalCenter="0"/>
    <s:TextInput y="250" width="229" textAlign="center" id="txtUsername" enter="txtUsername_enterHandler(event)" color="#090909"
horizontalCenter="0" height="27" fontWeight="bold" borderAlpha="0.99" contentBackgroundColor="#989A9C"/>
</s:Application>