Simple add child issue

Question

stupidly i try to add child mc "green" to "scroll_mc", but green is not visible.
package {
          import fl.containers.ScrollPane;
          import fl.controls.ScrollPolicy;
          import flash.desktop.NativeApplication;
          import flash.desktop.SystemIdleMode;
          import flash.display.MovieClip;
          import flash.media.Video;
          import flash.net.NetConnection;
          import flash.net.NetStream;
          import flash.events.MouseEvent;
          import flash.events.NetStatusEvent;
          import fl.controls.List
          import flash.events.Event;
                    public class Main extends MovieClip {
                              private var song:Array=["lego.flv","hatizmoret.flv","shir_hageshem.flv","ez.flv","tarnegol.flv","se_u gdi.flv","dag.flv","lizard.flv","toy_train_set_qt.flv","hadubim.flv","geveret_shfanfana.fl v",
                                                                                                    "parash_ben_hail.flv","snake.flv","pil_ pilon.flv","cat.flv","gan_shelanu.flv","purrfect_birthday_qt.flv","nadneda.flv","hatul_gan av.flv",
                                                                                                    "yonatan_hakatan.flv","dog.flv","aviron .flv","zipor.flv","hipo.flv","ladod_moshe.flv","shafan.flv","hipushit.flv","achbar.flv","t olaat.flv","zefardea.flv","dov.flv",
                                                                                                    "shaon_ben_hail.flv","kof.flv","hayom_y om_huledet.flv","ima_yekara.flv","oniya.flv","bee_and_flowers_qt.flv ","hasida.flv","ima_avaza.flv","yedidi_tintan.flv","donkey.flv",
                                                                                                    "haoto_shelanu.flv","bimdinat_hagamadim .flv"]
                    public var song_number:String
                    private var netConnection:NetConnection;
                    private var netStream:NetStream;
                    private var video:Video;
                    private var VIDEO_URL:String;
                    public var speed:Number;
  public var speedArray:Array;
  public var prevY:Number;
                    public var DRAG:Number = 20;
                    public var HEIGHT:int = 310;
                    public function Main() {
                              public var scroll_mc:MovieClip
                              public var Green:MovieClip=new green()
                              public var posX:int= 10;
                              public var posY:int =20;
                              scroll_mc.addChild(Green)
                              Green.x=posX
                              Green.y=posY
                              trace(Green.x)
                              scroll_mc.addEventListener(MouseEvent.MOUSE_DOWN, onDown);
                              NativeApplication.nativeApplication.systemIdleMode = SystemIdleMode.KEEP_AWAKE;
                              netConnection = new NetConnection();
                              netConnection.connect(null);
                              netStream = new NetStream(netConnection);
                              netStream.client = this;
                              netStream.addEventListener(NetStatusEvent.NET_STATUS, statusUpdated);
                              video = new Video();
                              video.attachNetStream(netStream);
                              video.width = 480;
                              video.height = 320;
                              addChildAt(video, 0);
                    private function  fl_ClickToGoToAndStopAtFrame_2(event:MouseEvent):void
          gotoAndStop(2);
                    function onDown(evt:MouseEvent):void {
                    speedArray = new Array(0,0,0,0,0,0,0,0,0,0);
                    speed = 0;
                    prevY = this.mouseY;
                    stage.addEventListener(Event.ENTER_FRAME, onDownEnter);
                    stage.addEventListener(MouseEvent.MOUSE_UP, onUp);
                    function onDownEnter(evt:Event):void {
                    var sp = this.mouseY - prevY;
                    scroll_mc.y += sp;
                    if (scroll_mc.y < (HEIGHT-scroll_mc.height)) {
                    scroll_mc.y = (HEIGHT-scroll_mc.height);
                    else if (scroll_mc.y > 0) {
                    scroll_mc.y = 0;
                    speedArray.push(sp);
                    speedArray.shift();
                    prevY = this.mouseY;
                    function onUp(evt:MouseEvent):void {
                    stage.removeEventListener(Event.ENTER_FRAME, onDownEnter);
                    stage.removeEventListener(MouseEvent.MOUSE_UP, onUp);
                    speed = 0;
                    for (var i:int = 0; i<speedArray.length; i++) {
                    speed += speedArray[i];
                    speed /= speedArray.length;
                    addEventListener(Event.ENTER_FRAME, onEnter);
                    function onEnter(evt:Event):void {
                    if (Math.abs(speed) < .5) {
                    speed = 0;
                    if (speed < 0) {
                    if (scroll_mc.y > (HEIGHT-scroll_mc.height) - speed) {
                    scroll_mc.y += speed;
                    speed -= speed/DRAG;
                    else {
                    scroll_mc.y = (HEIGHT-scroll_mc.height);
                    speed = 0;
                    else {
                    if (scroll_mc.y < 0-speed) {
                    scroll_mc.y += speed;
                    speed -= speed/DRAG;
                    else {
                    scroll_mc.y = 0;
                    speed = 0;
                    public function itemClick(event:Event):void{
                              if(event.target.selectedItem.label==" קוביות לי יש"){
                                        gotoAndStop(2)
                                        song_number=song[0]
                              if(event.target.selectedItem.label=="התזמורת"){
                                        gotoAndStop(2)
                                        song_number=song[1]
                              if(event.target.selectedItem.label=="שי ר הגשם"){
                                        gotoAndStop(2)
                                        song_number=song[2]
                              if(event.target.selectedItem.label==" יש לנו תיש "){
                                        gotoAndStop(2)
                                        song_number=song[3]
                              if(event.target.selectedItem.label==" גברת תרנגולת "){
                                        gotoAndStop(2)
                                        song_number=song[4]
                              if(event.target.selectedItem.label==" שה וגדי"){
                                        gotoAndStop(2)
                                        song_number=song[5]
                              if(event.target.selectedItem.label==" דג קטן"){
                                        gotoAndStop(2)
                                        song_number=song[6]
                              if(event.target.selectedItem.label==" הלטאה"){
                                        gotoAndStop(2)
                                        song_number=song[7]
                              if(event.target.selectedItem.label==" הנה באה הרכבת"){
                                        gotoAndStop(2)
                                        song_number=song[8]
                              if(event.target.selectedItem.label=="הדובים"){
                                        gotoAndStop(2)
                                        song_number=song[9]
                              if(event.target.selectedItem.label==" לשפן יש בית"){
                                        gotoAndStop(2)
                                        song_number=song[10]
                              if(event.target.selectedItem.label==" רוץ בן סוסי"){
                                        gotoAndStop(2)
                                        song_number=song[11]
                              if(event.target.selectedItem.label==" הנחש"){
                                        gotoAndStop(2)
                                        song_number=song[12]
                              /*if(event.target.selectedItem.label==" במדינת הגמדים"){
                                        gotoAndStop(2)
                                        song_number=song[42]
                              if(event.target.selectedItem.label==" במדינת הגמדים"){
                                        gotoAndStop(2)
                                        song_number=song[42]
                              if(event.target.selectedItem.label==" במדינת הגמדים"){
                                        gotoAndStop(2)
                                        song_number=song[42]
                              if(event.target.selectedItem.label==" במדינת הגמדים"){
                                        gotoAndStop(2)
                                        song_number=song[42]
                              if(event.target.selectedItem.label==" במדינת הגמדים"){
                                        gotoAndStop(2)
                                        song_number=song[42]
                              if(event.target.selectedItem.label==" במדינת הגמדים"){
                                        gotoAndStop(2)
                                        song_number=song[42]
                              if(event.target.selectedItem.label==" במדינת הגמדים"){
                                        gotoAndStop(2)
                                        song_number=song[42]
                              if(event.target.selectedItem.label==" במדינת הגמדים"){
                                        gotoAndStop(2)
                                        song_number=song[42]
                              if(event.target.selectedItem.label==" במדינת הגמדים"){
                                        gotoAndStop(2)
                                        song_number=song[42]
                              if(event.target.selectedItem.label==" במדינת הגמדים"){
                                        gotoAndStop(2)
                                        song_number=song[42]
                              if(event.target.selectedItem.label==" במדינת הגמדים"){
                                        gotoAndStop(2)
                                        song_number=song[42]
                              if(event.target.selectedItem.label==" במדינת הגמדים"){
                                        gotoAndStop(2)
                                        song_number=song[42]
                              if(event.target.selectedItem.label==" במדינת הגמדים"){
                                        gotoAndStop(2)
                                        song_number=song[42]
                              if(event.target.selectedItem.label==" במדינת הגמדים"){
                                        gotoAndStop(2)
                                        song_number=song[42]
                              if(event.target.selectedItem.label==" במדינת הגמדים"){
                                        gotoAndStop(2)
                                        song_number=song[42]
                              if(event.target.selectedItem.label==" במדינת הגמדים"){
                                        gotoAndStop(2)
                                        song_number=song[42]
                              if(event.target.selectedItem.label==" במדינת הגמדים"){
                                        gotoAndStop(2)
                                        song_number=song[42]
                              if(event.target.selectedItem.label==" במדינת הגמדים"){
                                        gotoAndStop(2)
                                        song_number=song[42]
                              if(event.target.selectedItem.label==" במדינת הגמדים"){
                                        gotoAndStop(2)
                                        song_number=song[42]
                              if(event.target.selectedItem.label==" במדינת הגמדים"){
                                        gotoAndStop(2)
                                        song_number=song[42]
                              if(event.target.selectedItem.label==" במדינת הגמדים"){
                                        gotoAndStop(2)
                                        song_number=song[42]
                              if(event.target.selectedItem.label==" במדינת הגמדים"){
                                        gotoAndStop(2)
                                        song_number=song[42]
                              if(event.target.selectedItem.label==" במדינת הגמדים"){
                                        gotoAndStop(2)
                                        song_number=song[42]
                              if(event.target.selectedItem.label==" במדינת הגמדים"){
                                        gotoAndStop(2)
                                        song_number=song[42]
                              if(event.target.selectedItem.label==" במדינת הגמדים"){
                                        gotoAndStop(2)
                                        song_number=song[42]
                              if(event.target.selectedItem.label==" במדינת הגמדים"){
                                        gotoAndStop(2)
                                        song_number=song[42]
                              if(event.target.selectedItem.label==" במדינת הגמדים"){
                                        gotoAndStop(2)
                                        song_number=song[42]
                              if(event.target.selectedItem.label==" במדינת הגמדים"){
                                        gotoAndStop(2)
                                        song_number=song[42]
                              if(event.target.selectedItem.label==" במדינת הגמדים"){
                                        gotoAndStop(2)
                                        song_number=song[42]
                              setupControls();
                    public function onMetaData(dataObj:Object):void {
                              ; // Do nothing.
                    public function onXMPData(dataObj:Object):void {
                              ; // Do nothing.
                    private function statusUpdated(e:NetStatusEvent):void {
                              if(e.info.code == "NetStream.Play.Stop")
                                        showBtns(["playBtn"]);
                    private function setupControls():void {
                              controls.playBtn.addEventListener(MouseEvent.MOUSE_UP, playVideo);
                              controls.restartBtn.addEventListener(MouseEvent.MOUSE_UP, restartVideo);
                              controls.resumeBtn.addEventListener(MouseEvent.MOUSE_UP, resumeVideo);
                              stage.addEventListener(MouseEvent.MOUSE_UP, pauseVideo);
                              showBtns(["playBtn"]);
private function playVideo(e:MouseEvent):void {
VIDEO_URL = "http://www.tovale.co.il/ktantanim/"+song_number
netStream.play(VIDEO_URL);
hideBtns();
e.stopPropagation();
trace(VIDEO_URL)
trace(song_number)
                    private function pauseVideo(e:MouseEvent):void {
                              if(controls.visible == false)
                                        netStream.pause();
                                        showBtns(["resumeBtn", "restartBtn"]);
                    private function restartVideo(e:MouseEvent):void {
                              netStream.seek(0);
                              netStream.resume();
                              hideBtns();
                              e.stopPropagation();
                    private function resumeVideo(e:MouseEvent):void {
                              netStream.resume();
                              hideBtns();
                              e.stopPropagation();
                    private function hideBtns():void {
                              controls.visible = false;
                              blocker.visible = false;
                    private function showBtns(btns:Array):void {
                              controls.visible = true;
                              blocker.visible = true;
                              for(var instName:String in controls)
                                        if(btns.indexOf(instName) != -1)
                                                  controls[instName].visible = true;
                                        else
                                                  controls[instName].visible = false;

Answer 1

You should be declaring your public variables in the public space like the rest... otherwise they only have scope within the function you place them in.
You declare a scroll_mc but you do not create an instance of it.
You should explain more about the problem and only include the code that is relevant to it.