var myXML:XML = new XML();
//step 1st add new XML
myXML.ignoreWhite = true;
//step 2nd remove white space of xml in node
myXML.load("Slider.xml");

//Load xml
myXML.onLoad = function() {
_root.SliderWidth = myXML.firstChild.attributes.width;//width of slider
_root.SliderHeight = myXML.firstChild.attributes.height;//height of slider
_root.Slider_Y = myXML.firstChild.attributes.y;//y position of slider
_root.Image_width = myXML.firstChild.attributes.image_width;//width of images of slider
_root.Vertical_spacing = myXML.firstChild.attributes.vertical_spacing;//vetical spacing of slider from top
_root.bar_y = Number(_root.SliderHeight)+Number(_root.Vertical_spacing);//adjust bar of slider
//flash takes as a number by apply "Number"
_root.Bar_thickness = myXML.firstChild.attributes.bar_thickness;//adjust bar thickness of slider
_root.scroll_width = _root.Bar_thickness*2;//width of scroll of slider
_root.myImages = myXML.firstChild.childNodes;//loading of slider
_root.myTotalImages = _root.myImages.length;//images are loading in myTotalImages variable

//for big images
_root.bigSlider_width = myXml.firstChild.attributes.gallery_width;//width for big gallery
_root.bigSlider_height = myXml.firstChild.attributes.gallery_height;//height for big gallery
_root.BigSlide_y = myXml.firstChild.attributes.slide_y;//y position for big gallery
_root.bigImages_width = myXML.firstChild.attributes.bigImages_width;//width of images of Bigslider
_root.vertical_Bigspacing = myXML.firstChild.attributes.vertical_Bigspacing;//vetical spacing of slider from top
_root.BigImages = myXML.firstChild.childNodes;//loading of slider
_root.TotalBigImages = _root.BigImages.length;
//trace(myXML);
myContainer();
BigContainer();
callImages();
masking();
scrollBar();
scroller();
_root.iCount=0;
};
//small gallery
function myContainer() {
_root.myGallery = _root.createEmptyMovieClip("myGallery", _root.getNextHighestDepth());
_root.myGallery._y = _root.Slider_Y;
_root.myGallery._x = _root.Image_width;
trace("myContainer");
}
//Big gallery
function BigContainer() {
var tm=new Date().getTime();
trace™;
_root.BigGallery = _root.createEmptyMovieClip("BigGallery"+tm, _root.getNextHighestDepth());
_root.BigGallery._y = _root.bigImages_width/2;
_root.BigGallery._x = _root.bigImages_width;
trace("BigGallery");

}

// call small Images
function callImages() {
_root.myImages_mc = _root.myGallery.createEmptyMovieClip("myImages_mc", _root.myGallery.getNextHighestDepth());
var myMCL:MovieClipLoader = new MovieClipLoader();
//var myMCL = new Object();
//myMCL.addListener(preloader);
for (i=0; i<_root.myTotalImages; i++) {
imageURL = _root.myImages[i].attributes.thumbs_url;
image_mc = _root.myImages_mc.createEmptyMovieClip(i, myImages_mc.getNextHighestDepth());
image_mc._x = _root.Image_width*i;
myMCL.loadClip("thumbs/" + imageURL,image_mc);

_root.myImages_mc.onRelease = function()
{

CallMe(_root.myImages_mc);
}
}
trace("LOAD");
}

CallMe =function(ctrl)
{
trace("Nits" + ctrl);
//myImages_Big.loadMovie(this.image_B);
//new code
if(_root.iCount>_root.myTotalImages-1)
{
_root.iCount=0;
}
//callBigImages(_root.iCount);

showBigImg(iCount);
_root.iCount+=1;
}

function showBigImg(ichk)
{
trace("nish--" + ichk)
_root.myBigImages =_root.BigGallery.createEmptyMovieClip("myBigImages", _root.BigGallery.getNextHighestDepth());
trace(_root.myBigImages + "ASDASDASd " + ichk);
var myBMCL:MovieClipLoader = new MovieClipLoader();
for (var i=0; i<_root.myTotalImages; i++) { */
Date().getTime();
imageBURL =myXML.childNodes[0].childNodes[ichk].attributes.mainurl;
image_Bmc._x = 0;
trace(imageBURL);
myBMCL.unloadClip(image_Bmc);
image_Bmc = _root.myBigImages.createEmptyMovieClip(ichk, myBigImages.getNextHighestDepth());
myBMCL.loadClip("Images/" + imageBURL,image_Bmc);
myBMCL=null;
image_Bmc=null;
BigContainer();

}
/ ********************************************************************************
*********************************/

// for small images
function masking() {
_root.Mask_mc = _root.myGallery.createEmptyMovieClip("Mask_mc", _root.myGallery.getNextHighestDepth());
_root.Mask_mc.beginFill(0x000000, 100);
_root.Mask_mc.lineTo(_root.SliderWidth, 0);
_root.Mask_mc.lineTo(_root.SliderWidth, _root.SliderHeight);
_root.Mask_mc.lineTo(0, _root.SliderHeight);
_root.Mask_mc.lineTo(0, 0);
_root.Mask_mc.endFill();
_root.myImages_mc.setMask(_root.Mask_mc);
trace("masking");
}
// for big images
function maskingBig() {
_root.Mask_B = _root.BigGallery.createEmptyMovieClip("Mask_B", _root.BigGallery.getNextHighestDepth());
_root.Mask_B.beginFill(0x000000, 100);
_root.Mask_B.lineTo(_root.bigSlider_width, 0);
_root.Mask_B.lineTo(_root.bigSlider_width, _root.bigSlider_height);
_root.Mask_B.lineTo(0, _root.bigSlider_height);
_root.Mask_B.lineTo(0, 0);
_root.Mask_B.endFill();
_root.myImages_Big.setMask(_root.Mask_B);
trace("maskingB");
}

function scrollBar() {
_root.scrollBar_mc = _root.myGallery.createEmptyMovieClip("scrollBar_mc", _root.myGallery.getNextHighestDepth());
_root.scrollBar_mc._y = _root.bar_y;
_root.scrollBar_mc.beginFill(0x404040, 100);
_root.scrollBar_mc.lineTo(_root.SliderWidth, 0);
_root.scrollBar_mc.lineTo(_root.SliderWidth, _root.Bar_thickness);
_root.scrollBar_mc.lineTo(0, _root.Bar_thickness);
_root.scrollBar_mc.lineTo(0, 0);
_root.scrollBar_mc.endFill();
_root.scrollBar_mc.onPress = function()
{
_root.scroller_mc._x=this._xmouse;
if(_root.scroller_mc._x >(this._width-_root.scroller_mc._width))
{
_root.scroller_mc._x = this._width-_root.scroller_mc._width;
}
mover();
}
trace("scrollBar");
}
function scroller () {
_root.scroller_mc = _root.myGallery.createEmptyMovieClip("scroller_mc", _root.myGallery.getNextHighestDepth());
_root.scroller_mc._y = _root.bar_y;

_root.scroller_mc.beginFill(0xFF0000,100);
_root.scroller_mc.lineTo(_root.scroll_width,0);
_root.scroller_mc.lineTo(_root.scroll_width,_root.Bar_thickness);
_root.scroller_mc.lineTo(0,_root.Bar_thickness);
_root.scroller_mc.lineTo(0,0);
_root.scroller_mc.endFill();
_root.scroller_mc.onPress = function()
{
startDrag(this,false,0,this._y,_root.scrollBar_mc._width-this._width,this._y);
}
_root.scroller_mc.onRelease = function()
{
stopDrag();
mover();
}
trace("scroller");
}
import mx.transitions.Tween;
import mx.transitions.easing.*;

function mover(){
var scrollerLocation = _root.scroller_mc._x/(_root.scrollBar_mc._width-_root.scroller_mc._width);
var galleryLocation = scrollerLocation*(_root.Mask_mc._width-_root.myImages_mc._width);

new Tween (_root.myImages_mc, "_x", Strong.easeOut, _root.myImages_mc._x, galleryLocation, 1.5, true);
trace("MOVES");
}

When creating the thumbnail image, save the large image's url as a property of the thumbnail object, and then reference it from within your onRelease handler.

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