var $ = function (id) 
    {
	    return "string" == typeof id ? document.getElementById(id) : id;
    };
 
    var Class = 
    {
        create: function() 
        {
	        return function() 
	        {
	            this.initialize.apply(this, arguments);
	        }
        }
    }
 
    Object.extend = function(destination, source) 
    {
	    for (var property in source) 
	    {
		    destination[property] = source[property];
	    }
	    return destination;
    }
 
    var TransformView = Class.create();
    TransformView.prototype = {
        //容器对象,滑动对象,切换参数,切换数量
        initialize: function(container, slider, parameter, count, options) 
        {
            if(parameter <= 0 || count <= 0) return;
            var oContainer = $(container), oSlider = $(slider), oThis = this;
 
            this.Index = 0;//当前索引
 
            this._timer = null;//定时器
            this._slider = oSlider;//滑动对象
            this._parameter = parameter;//切换参数
            this._count = count || 0;//切换数量
            this._target = 0;//目标参数
 
            this.SetOptions(options);
 
            this.Up = !!this.options.Up;
            this.Step = Math.abs(this.options.Step);
            this.Time = Math.abs(this.options.Time);
            this.Auto = !!this.options.Auto;
            this.Pause = Math.abs(this.options.Pause);
            this.onStart = this.options.onStart;
            this.onFinish = this.options.onFinish;
 
            oContainer.style.overflow = "hidden";
            oContainer.style.position = "relative";
 
            oSlider.style.position = "absolute";
            oSlider.style.top = oSlider.style.left = 0;
        },
        //设置默认属性
        SetOptions: function(options) 
        {
	        this.options = {//默认值
            Up:			true,//是否向上(否则向左)
            Step:		5,//滑动变化率
            Time:		1,//滑动延时
            Auto:		true,//是否自动转换
            Pause:		2000,//停顿时间(Auto为true时有效)
            onStart:	function(){},//开始转换时执行
            onFinish:	function(){}//完成转换时执行
        };
        Object.extend(this.options, options || {});
    },
    //开始切换设置
    Start: function() 
    {
        if(this.Index < 0)
        {
            this.Index = this._count - 1;
        } 
        else if (this.Index >= this._count)
        { 
            this.Index = 0; 
        }
 
        this._target = -1 * this._parameter * this.Index;
        this.onStart();
        this.Move();
    },
    //移动
    Move: function() 
    {
        clearTimeout(this._timer);
        var oThis = this, style = this.Up ? "top" : "left", iNow = parseInt(this._slider.style[style]) || 0, iStep = this.GetStep(this._target, iNow);
 
        if (iStep != 0) 
        {
            this._slider.style[style] = (iNow + iStep) + "px";
            this._timer = setTimeout(function()
            { 
                oThis.Move(); 
            }, this.Time);
        } 
        else 
        {
            this._slider.style[style] = this._target + "px";
            this.onFinish();
            if (this.Auto) 
            { 
                this._timer = setTimeout(function()
                { 
                    oThis.Index++; oThis.Start(); 
                }, this.Pause); 
            }
        }
    },
    //获取步长
    GetStep: function(iTarget, iNow) 
    {
        var iStep = (iTarget - iNow) / this.Step;
        if (iStep == 0) return 0;
            if (Math.abs(iStep) < 1) 
                return (iStep > 0 ? 1 : -1);
        return iStep;
    },
    //停止
    Stop: function(iTarget, iNow) 
    {
        clearTimeout(this._timer);
        this._slider.style[this.Up ? "top" : "left"] = this._target + "px";
    }
    };
 
    window.onload=function()
    {
	    function Each(list, fun)
	    {
		    for (var i = 0, len = list.length; i < len; i++) 
		    { 
		        fun(list[i], i); 
		    }
	    };
    	
	    var objs = $("idNum").getElementsByTagName("li");
    	
	    var tv = new TransformView("idTransformView", "idSlider", 221, 4, {
		    onStart : function()
		    { 
		        Each(objs, function(o, i)
		        { 
		            o.className = tv.Index == i ? "on" : ""; 
		        }) 
		    }//按钮样式
	    });
    	
	    tv.Start();
    	
	    Each(objs, function(o, i)
	    {
		    o.onmouseover = function()
		    {
			    o.className = "on";
			    tv.Auto = false;
			    tv.Index = i;
			    tv.Start();
		    }
		    o.onmouseout = function()
		    {
			    o.className = "";
			    tv.Auto = true;
			    tv.Start();
		    }
	    })
    	
	
    	
    }