function chgItem(index){
		var spanObj = null,pObj = null;	
		for(var i=0;i<5;i++){
			spanObj = document.getElementById("title"+i);
			pObj = document.getElementById("content"+i);
			if(index == i){
				if(spanObj){
					spanObj.firstChild.className = "cur";
				}
				if(pObj) pObj.className = "cur";
			}else{
				if(spanObj) spanObj.firstChild.className = "";
				if(pObj) pObj.className = "";
			}
		}
	}
  
 
var s=function(){
	var interv=6000; //切换间隔时间
	var interv2=30; //切换速速
	var opac1=0; //文字背景的透明度
	var source="fade_focus" //焦点轮换图片容器的id名称
 
 function chgpic(){if (document.documentElement.clientWidth<1024){
	document.getElementById("banner1").src="images/banner1_1002.jpg";
	document.getElementById("banner2").src="images/banner2_1002.jpg";
	document.getElementById("banner3").src="images/banner3_1002.jpg";
	document.getElementById("banner4").src="images/banner4_1002.jpg";
	document.getElementById("banner5").src="images/banner5_1002.jpg";
	document.getElementById("banner6").src="images/banner6_1002.jpg";
	
	}else if(document.documentElement.clientWidth<1280){
		document.getElementById("banner1").src="images/banner1_1260.jpg";
	document.getElementById("banner2").src="images/banner2_1260.jpg";
	document.getElementById("banner3").src="images/banner3_1260.jpg";
	document.getElementById("banner4").src="images/banner4_1260.jpg";
	document.getElementById("banner5").src="images/banner5_1260.jpg";
	document.getElementById("banner6").src="images/banner6_1260.jpg";
	 
}
	} 
	document.getElementById("banner1").src="images/banner1_1420.jpg";
	document.getElementById("banner2").src="images/banner2_1420.jpg";
	document.getElementById("banner3").src="images/banner3_1420.jpg";
	document.getElementById("banner4").src="images/banner4_1420.jpg";
	document.getElementById("banner5").src="images/banner5_1420.jpg";
	document.getElementById("banner6").src="images/banner5_1420.jpg";

chgpic();
function getTag(tag,obj){if(obj==null){
	return document.getElementsByTagName(tag)
	}else{
		return obj.getElementsByTagName(tag)
		}
	}
function getid(id){
	return document.getElementById(id)
	};
	var opac=0,j=0,t=63,num,scton=0,timer,timer2,timer3;
	var id=getid(source);id.removeChild(getTag("div",id)[0]);
	var li=getTag("li",id);var div=document.createElement("div");
	var title=document.createElement("div");
	var span=document.createElement("span");
	var button=document.createElement("div");
	button.className="button";
	for(var i=0;i<li.length;i++){
		var a=document.createElement("a");a.innerHTML=i+1;
		a.onclick=function(){
			clearTimeout(timer);
			clearTimeout(timer2);
			clearTimeout(timer3);
			j=parseInt(this.innerHTML)-1;scton=0;t=63;opac=0;fadeon();
		};
	a.className="b1";a.onmouseover=function(){
		this.className="b2"
		};
	a.onmouseout=function(){
		this.className="b1";sc(j)
		};
	button.appendChild(a);
	
}
//控制图层透明度
function alpha(obj,n){
	if(document.all){
		obj.style.filter="alpha(opacity="+n+")";
		}else{
			obj.style.opacity=(n/100);}
			}
//控制焦点按钮
function sc(n){
	
	for(var i=0;i<li.length;i++){
		button.childNodes[i].className="b1"};button.childNodes[n].className="b2"
		;}
	title.className="num_list";
	title.appendChild(span);
	alpha(title,opac1);
	id.className="d1";
	div.className="d2";
	id.appendChild(div);
	id.appendChild(title);
	id.appendChild(button);
//渐显
var fadeon=function(){
	opac+=5;
	div.innerHTML=li[j].innerHTML;
	span.innerHTML=getTag("img",li[j])[0].alt;
	alpha(div,opac);
	if(scton==0){
		sc(j);num=-2;scrolltxt();
		scton=1};
	if(opac<100){
		timer=setTimeout(fadeon,interv2)
		}else{
			timer2=setTimeout(fadeout,interv);
			};
		}
//渐隐
var fadeout=function(){
	opac-=5;
	div.innerHTML=li[j].innerHTML;
	alpha(div,opac);
	if(scton==0){
		num=2;
		scrolltxt();
		scton=1};if(opac>0){
			timer=setTimeout(fadeout,interv2)
			}else{if(j<li.length-1){
				j++}else{j=0};
				fadeon()
				}
			;}
//滚动文字
var scrolltxt=function(){
	t+=num;span.style.marginTop=t+"px";
	if(num<0&&t>3){
		timer3=setTimeout(scrolltxt,interv2)
		}else if(num>0&&t<62){
			timer3=setTimeout(scrolltxt,interv2)}else{
				scton=0}
				};
	fadeon();
}
//初始化
window.onload=s;