<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title></title>
<style type="text/css">
*{
margin:0;
padding:0;
}
#ul1{
width:400px;
height:400px;
background-color: skyblue;
margin:20px auto;
position:relative;
}
#ul1 li{
width:100px;
height:100px;
background-color: #9e9e9e;
float: left;
list-style: none;
text-align: center;
line-height: 100px;
margin-left: 25px;
margin-top: 25px;
cursor: pointer;
}
</style>
</head>
<body>
<input type="button" id="input1" value="随机"/>
<ul id="ul1">
<li>1</li>
<li>2</li>
<li>3</li>
<li>4</li>
<li>5</li>
<li>6</li>
<li>7</li>
<li>8</li>
<li>9</li>
</ul>
</body>
<script src="js/tween.js"></script>
<script>
var oUl = document.getElementById('ul1');
var oInput = document.getElementById('input1');
var aLi = oUl.getElementsByTagName('li');
var izIndex = 1;
var arr2 = [];
//布局转换，把浮动布局转换成定位布局
var arr = [];
for(var i=0;i<aLi.length;i++){
//把每一项的top值和left值都存入数组中
arr.push({'left': aLi[i].offsetLeft,'top': aLi[i].offsetTop});
}
for(var i=0;i<aLi.length;i++){
aLi[i].style.position = 'absolute';
aLi[i].style.top = arr[i].top + 'px';
aLi[i].style.left = arr[i].left + 'px';
aLi[i].style.margin = 0;
}
//拖拽
for(var i=0;i<aLi.length;i++){
aLi[i].index = i;
drag(aLi[i]);
}
function drag(obj){
obj.onmousedown = function(ev){
var ev = ev || window.event;
var disX = ev.clientX - obj.offsetLeft;
var disY = ev.clientY - obj.offsetTop;
//确保被拖拽的元素的层级永远最高，不被覆盖
obj.style.zIndex = izIndex++;
document.onmousemove = function(ev){
var ev = ev || window.event;
obj.style.left = ev.clientX - disX +'px';
obj.style.top = ev.clientY - disY +'px';
for(var i=0;i<aLi.length;i++){
aLi[i].style.border = '';
}
var nL = nearby(obj);
if(nL){
nL.style.border = '1px solid red';
}
}
document.onmouseup = function(){
document.onmousemove = null;
document.onmouseup = null;
var nL = nearby(obj);
//运动
if(nL){
starMove(nL,{left:arr[obj.index].left,top:arr[obj.index].top},500,'easeOut');
starMove(obj,{left:arr[nL.index].left,top:arr[nL.index].top},500,'easeOut');
nL.style.border = '';
//索引转换
var changeIndex = nL.index;
nL.index = obj.index;
obj.index = changeIndex;
}else{
//如果没有碰撞还回到原始位置
starMove(obj,{left:arr[obj.index].left,top:arr[obj.index].top},500,'easeOut');
}
}
return false;
}
}
//碰撞
function isCollision(obj,obj2){
var T1 = obj.offsetTop;
var L1 = obj.offsetLeft;
var R1 = obj.offsetLeft + obj.offsetWidth;
var B1 = obj.offsetTop + obj.offsetHeight;
var T2 = obj2.offsetTop;
var L2 = obj2.offsetLeft;
var R2 = obj2.offsetLeft + obj2.offsetWidth;
var B2 = obj2.offsetTop + obj2.offsetHeight;
if(R1<L2 || L1>R2 || B1<T2 || T1>B2 ){ //碰不到的情况
return false;
}else{
return true;
}
}
function nearby(obj){
var value = 9999;
var index = -1;
for(var i=0;i<aLi.length;i++){
if(isCollision(obj,aLi[i]) && aLi[i] != obj){ //排除掉自身
var c = j1(obj,aLi[i]);
if(c<value){
value = c;
index = i;
}
}
}
if(index != -1){
return aLi[index];
}else{
return false;
}
}
function j1(obj1,obj2){
var a = obj1.offsetLeft - obj2.offsetLeft;
var b = obj1.offsetTop - obj2.offsetTop;
return Math.sqrt(a*a + b*b);
}
oInput.onclick = function(){
var randomArr = [0,1,2,3,4,5,6,7,8];
randomArr.sort(function(){
return Math.random()-0.5;
});
for(var i=0;i<aLi.length;i++){
starMove(aLi[i],{left:arr[randomArr[i]].left,top:arr[randomArr[i]].top},500,'easeOut');
//调换位置之后，index也对应变化
aLi[i].index = randomArr[i];
}
}
</script>
</html>
var Tween = {
linear: function (t, b, c, d){ //匀速
return c*t/d + b;
},
easeIn: function(t, b, c, d){ //加速曲线
return c*(t/=d)*t + b;
},
easeOut: function(t, b, c, d){ //减速曲线
return -c *(t/=d)*(t-2) + b;
},
easeBoth: function(t, b, c, d){ //加速减速曲线
if ((t/=d/2) < 1) {
return c/2*t*t + b;
}
return -c/2 * ((--t)*(t-2) - 1) + b;
},
easeInStrong: function(t, b, c, d){ //加加速曲线
return c*(t/=d)*t*t*t + b;
},
easeOutStrong: function(t, b, c, d){ //减减速曲线
return -c * ((t=t/d-1)*t*t*t - 1) + b;
},
easeBothStrong: function(t, b, c, d){ //加加速减减速曲线
if ((t/=d/2) < 1) {
return c/2*t*t*t*t + b;
}
return -c/2 * ((t-=2)*t*t*t - 2) + b;
},
elasticIn: function(t, b, c, d, a, p){ //正弦衰减曲线（弹动渐入）
if (t === 0) {
return b;
}
if ( (t /= d) == 1 ) {
return b+c;
}
if (!p) {
p=d*0.3;
}
if (!a || a < Math.abs(c)) {
a = c;
var s = p/4;
} else {
var s = p/(2*Math.PI) * Math.asin (c/a);
}
return -(a*Math.pow(2,10*(t-=1)) * Math.sin( (t*d-s)*(2*Math.PI)/p )) + b;
},
elasticOut: function(t, b, c, d, a, p){ //正弦增强曲线（弹动渐出）
if (t === 0) {
return b;
}
if ( (t /= d) == 1 ) {
return b+c;
}
if (!p) {
p=d*0.3;
}
if (!a || a < Math.abs(c)) {
a = c;
var s = p / 4;
} else {
var s = p/(2*Math.PI) * Math.asin (c/a);
}
return a*Math.pow(2,-10*t) * Math.sin( (t*d-s)*(2*Math.PI)/p ) + c + b;
},
elasticBoth: function(t, b, c, d, a, p){
if (t === 0) {
return b;
}
if ( (t /= d/2) == 2 ) {
return b+c;
}
if (!p) {
p = d*(0.3*1.5);
}
if ( !a || a < Math.abs(c) ) {
a = c;
var s = p/4;
}
else {
var s = p/(2*Math.PI) * Math.asin (c/a);
}
if (t < 1) {
return - 0.5*(a*Math.pow(2,10*(t-=1)) *
Math.sin( (t*d-s)*(2*Math.PI)/p )) + b;
}
return a*Math.pow(2,-10*(t-=1)) *
Math.sin( (t*d-s)*(2*Math.PI)/p )*0.5 + c + b;
},
backIn: function(t, b, c, d, s){ //回退加速（回退渐入）
if (typeof s == 'undefined') {
s = 1.70158;
}
return c*(t/=d)*t*((s+1)*t - s) + b;
},
backOut: function(t, b, c, d, s){
if (typeof s == 'undefined') {
s = 3.70158; //回缩的距离
}
return c*((t=t/d-1)*t*((s+1)*t + s) + 1) + b;
},
backBoth: function(t, b, c, d, s){
if (typeof s == 'undefined') {
s = 1.70158;
}
if ((t /= d/2 ) < 1) {
return c/2*(t*t*(((s*=(1.525))+1)*t - s)) + b;
}
return c/2*((t-=2)*t*(((s*=(1.525))+1)*t + s) + 2) + b;
},
bounceIn: function(t, b, c, d){ //弹球减振（弹球渐出）
return c - Tween['bounceOut'](d-t, 0, c, d) + b;
},
bounceOut: function(t, b, c, d){
if ((t/=d) < (1/2.75)) {
return c*(7.5625*t*t) + b;
} else if (t < (2/2.75)) {
return c*(7.5625*(t-=(1.5/2.75))*t + 0.75) + b;
} else if (t < (2.5/2.75)) {
return c*(7.5625*(t-=(2.25/2.75))*t + 0.9375) + b;
}
return c*(7.5625*(t-=(2.625/2.75))*t + 0.984375) + b;
},
bounceBoth: function(t, b, c, d){
if (t < d/2) {
return Tween['bounceIn'](t*2, 0, c, d) * 0.5 + b;
}
return Tween['bounceOut'](t*2-d, 0, c, d) * 0.5 + c*0.5 + b;
}
}
function getStyle(obj,attr)
{
if(obj.currentStyle){
return obj.currentStyle[attr];
}
else{
return getComputedStyle(obj,false)[attr];
}
}
function starMove(obj,json,time,fx,callBack)
{
var iNowTime=getNow();
var iCur={};
for(var attr in json)
{
if(attr=="opacity")
{
iCur[attr]=Math.round(getStyle(obj,attr)*100);
}
else
{
iCur[attr]=parseInt(getStyle(obj,attr));
}
}
clearInterval(obj.oTimer);
obj.oTimer=setInterval(function(){
var iTime=time-Math.max(0,iNowTime-getNow()+time);
for(var attr in json)
{
var iVal=Tween[fx](iTime,iCur[attr],json[attr]-iCur[attr],time)
if(attr=="opacity")
{
obj.style.opacity=iVal/100;
obj.style.filter="alpha(opacity="+iVal+")"
}
else
{
obj.style[attr]=iVal+"px";
}
}
if(iTime==time)
{
clearInterval(obj.oTimer);
if(callBack)
{
callBack.call(obj);
}
}
},14);
}
function getNow()
{
return new Date().getTime();
}
