When user enters and exits one movieclip, button changes color

Question

Hello,
I currently have a slideshow-style navigation site.  There are five buttons on the bottom and when the user clicks each button, it triggers a nested movieclip to play.  I would like the button to be highlighted when the corresponding movieclip is playing, but when they click another button and another movieclip plays, I want the button to go back to its original color.
The problem is that the movieclips that are playing are nested two levels down and the buttons have to be on the main timeline.  I think I might need an event listener to see if a certain nested movieclip is playing, to know to change the button color.  It seems to easy but I can't figure it out, thanks for any help!

Answer 1

Hi again!  Sorry, I keep changing my mind on whether I've figured this out or not.  Now I need the buttons to become disabled when they are highlighted and active.  I tried putting a:  btns[i].enabled = false;  in the else part of the for-else statement and it didn't work.  Where would I put that kind of code?  Thanks!
stop();
//attach sounds
Sound1 = new Sound();
Sound1.attachSound("Sound1");
Sound2 = new Sound();
Sound2.attachSound("Sound2");
Sound3 = new Sound();
Sound3.attachSound("Sound3");
//buttons
//nav buttons
b1.onRelease = function() {
    gotoAndStop(1);
    stopAllSounds()
    activeBtn(b1);
b2.onRelease = function() {
    gotoAndStop(2);
    stopAllSounds();
    activeBtn(b2);
b3.onRelease = function() {
    gotoAndStop(3);
    stopAllSounds();
    activeBtn(b3);
//array for highlighted button state
var btns:Array = [b1, b2, b3];
function activeBtn(mc:MovieClip):Void{
   for(var i:Number=0; i<btns.length; i++){
      if(btns[i]!=mc){
         btns[i].gotoAndStop("inactive");
      }else{
         btns[i].gotoAndStop("active");