Movieclip(root) doesn't work inside a function

Question

Hey everyone,
I'm having this problem.
In fact, when i publish my FLA with player 9, there is no prob.
When i publish with selecting player 10, there is this problem.
I paste my code :
var leng:int = MovieClip(root).program.websiteXML.pages.titlePage.length();
trace ("leng"+leng);
setInterval(function () : void {
          if (MovieClip(root).program.autoCh==true){
           trace("CHANGE");
          MovieClip(root).allContent.controllMenu2['itemButton_' + MovieClip(root).program.linkPic].gotoAndPlay("s4");
          if (MovieClip(root).program.linkPic < int(leng-1)){
                    MovieClip(root).program.linkPic++;
                       }else{
                           //MovieClip(root).allContent.play ();
                         MovieClip(root).program.autoCh=false;
                         MovieClip(root).program.linkPic=1;
                         MovieClip(root).allContent.controllMenu2['itemButton_' + MovieClip(root).program.linkPic].gotoAndPlay("s4");
                         for (var z:uint=1; z<(MovieClip(root).program.linkPic+1); z++) {
                              var tempMC:MovieClip = MovieClip(MovieClip(root).allContent.controllMenu2)["itemButton_"+z];
                              Tweener.addTween(tempMC, { x:(z-1)*(45+1)-353, time:1} );     
                         for (var j:uint=(MovieClip(root).program.linkPic+1); j<7; j++) {
                              var tempMC2:MovieClip = MovieClip(MovieClip(root).allContent.controllMenu2)["itemButton_"+j];
                              Tweener.addTween(tempMC2, { x:(j-1)*(45+1)+352, time:1} );     
                         MovieClip(root).allContent.controllMenu2['itemButton_' + MovieClip(root).program.linkPic].gotoAndPlay("s3");
                   }}, 4000);
For leng variable, there is no problem, the value is taken.
But it's inside SetIntervall, at
MovieClip(root).program.autoCh
it tells me that :
TypeError: Error #1009: Il est impossible d'accéder à la propriété ou à la méthode d'une référence d'objet nul.
    at Function/<anonymous>()[main6_cs3_fla._00button_136::frame1:32]
    at Function/http://adobe.com/AS3/2006/builtin::apply()
    at SetIntervalTimer/onTimer()
    at flash.utils::Timer/_timerDispatch()
    at flash.utils::Timer/tick()
And if I put the value outside the function :
var autoChtest = MovieClip(root).program.autoCh;
And use it :
if (autoChtest==true)
There is no errors but my function doesn't work correctly, as autoCh can be "false" in another action.
Well, I hope this will not scare you, and someone will try to help me, please.
If someone know anything about this issue or having same problem please tell me.
Thanks!

Answer 1

Ok i see more clearly, you know it's diificult for me to understand it because i'm into flash AS since a few weeks.
And what you say about the way setInterval is use, with the function in it, i'm totally agree with that, it's difficult to read.
The truth is that this is a template that I bought and it was like that, so to do what i've got to do i needed to change some AS3 code.
This is how it is now :
var rootvar = MovieClip(root).root;
function diapodebut (e:TimerEvent) : void {
    if (rootvar.program.autoCh==true){
        trace("CHANGE");       
        rootvar.allContent.controllMenu2['itemButton_' + rootvar.program.linkPic].gotoAndPlay("s4");
        if (rootvar.program.linkPic < int(leng-1)){
            rootvar.program.linkPic++;
        }else{
              //MovieClip(root).allContent.play ();
            rootvar.program.autoCh=false;
            rootvar.program.linkPic=1;
        rootvar.allContent.controllMenu2['itemButton_' + rootvar.program.linkPic].gotoAndPlay("s4");
        for (var $z:uint=1; $z<(rootvar.program.linkPic+1); $z++) {
            var tempMC:MovieClip = MovieClip(rootvar.allContent.controllMenu2)["itemButton_"+$z];
            Tweener.addTween(tempMC, { x:($z-1)*(45+1)-353, time:1} );   
        for (var j:uint=(rootvar.program.linkPic+1); j<7; j++) {
            var tempMC2:MovieClip = MovieClip(rootvar.allContent.controllMenu2)["itemButton_"+j];
            Tweener.addTween(tempMC2, { x:(j-1)*(45+1)+352, time:1} );   
        rootvar.allContent.controllMenu2['itemButton_' + rootvar.program.linkPic].gotoAndPlay("s3");
    else
        timerSynchro.stop( );
var leng:int = MovieClip(root).program.websiteXML.pages.titlePage.length();
trace ("leng"+leng);
var timerSynchro:Timer = new Timer( 4000, 6) ;
timerSynchro.addEventListener( TimerEvent.TIMER, diapodebut);
timerSynchro.start() ;
You can see that I use Timer class, i've seen on another website just what you say : use Timer instead of setInterval with AS3.
If you still find something wrong to you, tell me!
Thanks again for your help !