js div拖动动画运行轨迹效果

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>js div拖动动画运行轨迹效果</title>

var $ID = function(id){
return "string"==typeof id?document.getElementById(id):id;
}

var Class = {
create:function(){
return function(){
this.initilize.apply(this,arguments);
}
}
}

var Extend = function(destination, source){
for(var property in source){
destination[property] = source[property];
}
}

var Bind = function(object,fun){
var args = Array.prototype.slice.call(arguments).slice(2);
return function(){
return fun.apply(object,args);
}
}

var BindAsEventListener = function(object,fun){
var args = Array.prototype.slice.call(arguments).slice(2);
return function(event){
return fun.apply(object,[event||window.event].concat(args));
}
}

function getNodePosition(node,type){//type="left"or"top"
var nodeTemp = node;
var l = 0;
var t = 0;
while(nodeTemp!=document.body&&nodeTemp!=null){
l += nodeTemp.offsetLeft;
t += nodeTemp.offsetTop;
nodeTemp = nodeTemp.offsetParent;
}
if(type.toLowerCase()=="left") return l;
else return t;
}
//前面通常都用一个base.js封装
</script>

MyDrag.prototype = {
initilize:function(obj){
this.Obj = $ID(obj);
this._x = this._y = 0;
this._xx = this._yy = 0;//Move记录坐标
this.Obj.style.position = "absolute";
this._pos = [];
this._ifSavePos = true;
this._t = null;
this._speed = 10;
this._indexMove = 0;//全局的MoveIndex
this._fnStart = BindAsEventListener(this,this.Start);
this._fnMove = BindAsEventListener(this,this.Move);
this._fnStop = Bind(this,this.Stop);
addEventHandler(this.Obj,"mousedown",this._fnStart);
},
Start:function(oEvent){
if(!this._ifSavePos)
this._pos = [];
this.Drag = this.Obj.cloneNode(true);
if(isIE) this.Drag.style.filter = "alpha(opacity=50)";
else this.Drag.style.opacity = "0.5";
this.Obj.parentNode.appendChild(this.Drag);

this._left1 = this._xx = getNodePosition(this.Obj,"left");
this._top1 = this._yy = getNodePosition(this.Obj,"top");
this._x = oEvent.clientX - this.Obj.offsetLeft;
this._y = oEvent.clientY - this.Obj.offsetTop;
addEventHandler(document,"mousemove",this._fnMove);
addEventHandler(document,"mouseup",this._fnStop);
this._t = setInterval(Bind(this,this.SavePos),10);
},
SavePos:function(){//记录坐标点
this._pos.push(this._xx + "_" + this._yy);
},
Move:function(oEvent){
if(isIE) oEvent.returnValue = false;
this._xx = oEvent.clientX - this._x;
this._yy = oEvent.clientY - this._y;
this.Drag.style.left = this._xx + "px";
this.Drag.style.top = this._yy + "px";
},
Stop:function(){
removeEventHandler(document,"mousemove",this._fnMove);
removeEventHandler(document,"mouseup",this._fnStop);
this.Obj.parentNode.removeChild(this.Drag);
this.Obj.style.left = this._xx + "px";
this.Obj.style.top = this._yy + "px";
clearInterval(this._t);
this._fnCloneMove = Bind(this,this.CloneMove);
this._t = setTimeout(this._fnCloneMove,50);
},
CloneMove:function(){
if(this._indexMove<6){
new ObjMove({x1:this._left1,y1:this._top1,x2:this._xx,y2:this._yy,pos:this._pos});
this._indexMove++;
this._t = setTimeout(this._fnCloneMove,50);
}else{
clearTimeout(this._t);
this._indexMove = 0;
}
}
}

onload = function(){
var myDrag = new MyDrag("div1");
$ID("rad1").onclick = function(){
myDrag._ifSavePos = true;
}
$ID("rad2").onclick = function(){
myDrag._ifSavePos = false;
}
}
</script>

</head>
<body>
<center><br>
<div>随意拖动爱心几秒钟</div><br>

<label for="rad2"><input type="radio" id="rad2" name="rad"/>不记住轨迹</label>