分批载入：载入XML数与图片数不相同（一次载入25个xml图片地址，点击下一页载入5张图片）（存在BUG，未修复）

import flash.display.Loader;
import flash.net.URLRequest;
import flash.net.URLLoader;
import flash.events.Event;
import flash.display.Sprite;

var xmlURL:String="test.xml";
var xml:XML;
var arr_imgURL:Array=[];

var len:int;
var _value1:Number;
var _value2:Number;//用来判断最后一页是否包含5个图片
var pageNum:int;//总页数
var lastXmlPartIndex:int;//最后一段xml的索引号
var lastPartImgs:int;//最后一段xml中包含的图片数目
var lastPage:int;//最后一段xml中的最后一页索引号

var imgs_perPage:int=5;//每页图片数目
var pages_perXmlPart:int=5;//每段xml中包含页数
var imgs_perXmlPart:int=imgs_perPage*pages_perXmlPart;//每段xml中包含图片数目
var distance:int=10;

var page:int;
var xmlPartIndex:int;

var imgSprite:Sprite=new Sprite();
addChild(imgSprite);

//---------------------------------------------------------------------------------------------------
loadXML(xmlURL);

function loadXML(url:String):void {
	var xmlLoader:URLLoader=new URLLoader();
	xmlLoader.load(new URLRequest(url));
	xmlLoader.addEventListener(Event.COMPLETE,xmlLoaded,false,0,true);
}

function xmlLoaded(e:Event):void {
	xml=XML(e.currentTarget.data);
	len=xml.img.length();//图片总数
	_value1=len/imgs_perXmlPart;//xml段数（浮点值）
	_value2=len/imgs_perPage;//用来判断最后一页是否包含5个图片
	pageNum=Math.ceil(_value2);//总页数
	lastXmlPartIndex=Math.ceil(_value1);//最后一段xml的索引号
	lastPartImgs=len-(lastXmlPartIndex-1)*imgs_perXmlPart;//最后一段xml中包含的图片数目
	lastPage=Math.ceil(lastPartImgs/imgs_perPage);//最后一段xml中的最后一页索引号
	trace("len="+len);
	trace("_value1="+_value1);
	trace("_value2="+_value2);
	trace("pageNum="+pageNum);
	trace("lastXmlPartIndex="+lastXmlPartIndex);
	trace("lastPartImgs="+lastPartImgs);
	trace("lastPage="+lastPage);

	setImgURL(xmlPartIndex);
	loadImg(page);
	tf_page.text=String("当前页索引："+page);
	tf_xmlPartIndex.text=String("当前xml段号："+xmlPartIndex);

	prevBtn.addEventListener(MouseEvent.CLICK,prevBtnClick,false,0,true);
	nextBtn.addEventListener(MouseEvent.CLICK,nextBtnClick,false,0,true);
}

//---------------------------------------------------------------------------------------------------
function prevBtnClick(e:MouseEvent):void {
	removeImg();
	page--;
	if (page==-1) {
		xmlPartIndex--;
		page=pages_perXmlPart-1;
		setImgURL(xmlPartIndex);
	}
	loadImg(page);
	tf_page.text=String("当前页数："+page);
	tf_xmlPartIndex.text=String("当前xml段号："+xmlPartIndex);
}

function nextBtnClick(e:MouseEvent):void {
	removeImg();
	page++;
	if (page>lastPage) {
		return;
	}
	if (page==pages_perXmlPart) {
		xmlPartIndex++;
		page=0;
		setImgURL(xmlPartIndex);
	}
	loadImg(page);
	tf_page.text=String("当前页数："+page);
	tf_xmlPartIndex.text=String("当前xml段号："+xmlPartIndex);
}

//---------------------------------------------------------------------------------------------------
function setImgURL(xmlPartIndex:int):void {
	var startIndex:int;
	var endIndex:int;

	if (!(_value1 is int)&&xmlPartIndex==lastXmlPartIndex) {
		startIndex=imgs_perXmlPart*(lastXmlPartIndex-1);
		endIndex=len;
	} else {
		startIndex=imgs_perXmlPart*xmlPartIndex;
		endIndex=imgs_perXmlPart*(xmlPartIndex+1);
	}

	for (var i:int=startIndex; i<endIndex; i++) {
		var imgURL:String=xml.img[i].picture.@url;
		arr_imgURL[i-startIndex]=imgURL;
	}
}
//---------------------------------------------------------------------------------------------------
function loadImg(page:int):void {
	var startIndex:int=page*imgs_perPage;
	var endIndex:int;

	if (!(_value2 is int)&&xmlPartIndex==lastXmlPartIndex&&page==lastPage) {
		endIndex=lastPartImgs;
	} else {
		endIndex=(page+1)*imgs_perPage;
	}

	for (var i:int=startIndex; i<endIndex; i++) {
		var url:String=arr_imgURL[i];
		trace(url);
		var imgLoader:Loader=new Loader();
		imgLoader.name=String(i-startIndex);
		imgSprite.addChild(imgLoader);
		imgLoader.load(new URLRequest(url));
		imgLoader.contentLoaderInfo.addEventListener(Event.COMPLETE,imgLoaded,false,0,true);
	}
}

function imgLoaded(e:Event):void {
	var image:Loader=e.currentTarget.loader;
	var index:int=int(image.name);
	image.width=100;
	image.height=100;
	image.x=20+(image.width+distance)*index;
	image.y=100;
	trace("当前已载入的图片："+(index+page*pages_perXmlPart));
}
//---------------------------------------------------------------------------------------------------
function removeImg():void {
	var num:int=imgSprite.numChildren;
	for (var i:int=0; i<num-1; i++) {
		imgSprite.removeChildAt(0);
	}
}