<!doctype html>
<html>
<head>
<meta http-equiv="Content-type" content="text/html; charset=utf-8"/>
<style type="text/css">
button{
display: block;
}
</style>
<script src="http://code.jquery.com/jquery-latest.js"></script>
</head>
<body>
<button id="one">jQuery动画的模拟实现:left:50</button>
<button id="two">jQuery动画的模拟实现:left:500</button>
<ul id="book" alt="" style="background:red;opacity:1;position: relative; left: 300px;width:200px;height:100px;display:inline;"></ul>
<script type="text/javascript">
var book = document.getElementById('book');
var $book = $('#book');
var i = 10
while(i){
$book.append("<li>11</li>")
i--;
}
////////////
//创建动画缓动对象 //
////////////
function Tween(value, prop, animation) {
this.elem = animation.elem;
this.prop = prop;
this.easing = "swing"; //动画缓动算法
this.options = animation.options;
//获取初始值
this.start = this.now = this.get();
//动画最终值
this.end = value;
//单位
this.unit = "px"
}
function getStyles(elem) {
return elem.ownerDocument.defaultView.getComputedStyle(elem, null);
};
function swing(p) {
return 0.5 - Math.cos(p * Math.PI) / 2;
}
Tween.prototype = {
//获取元素的当前属性
get: function() {
var computed = getStyles(this.elem);
var ret = computed.getPropertyValue(this.prop) || computed[this.prop];
return parseFloat(ret);
},
//运行动画
run:function(percent){
var eased
//根据缓动算法改变percent
this.pos = eased = swing(percent);
//获取具体的改变坐标值
this.now = (this.end - this.start) * eased + this.start;
//最终改变坐标
this.elem.style[this.prop] = this.now + "px";
return this;
}
}
////////
//动画类 //
////////
function Animation(elem, properties, options){
//动画对象
var animation = {
elem : elem,
props : properties,
originalOptions : options,
options : options,
startTime : Animation.fxNow || createFxNow(),//动画开始时间
tweens : [] //存放每个属性的缓动对象，用于动画
}
//生成属性对应的动画算法对象
for (var k in properties) {
// tweens保存每一个属性对应的缓动控制对象
animation.tweens.push( new Tween(properties[k], k, animation) )
}
//动画状态
var stopped;
//动画的定时器调用包装器
var tick = function() {
if (stopped) {
return false;
}
//动画时间算法
var currentTime = Animation.fxNow || createFxNow
//运动时间递减
remaining = Math.max(0, animation.startTime + animation.options.duration - currentTime),
temp = remaining / animation.options.duration || 0,
percent = 1 - temp;
var index = 0,
length = animation.tweens.length;
//执行动画改变
for (; index < length; index++) {
//percent改变值
animation.tweens[index].run(percent);
}
//是否继续，还是停止
if (percent <= 1 && length) {
return remaining;
} else {
//停止
return false;
}
}
tick.elem = elem;
tick.anim = animation
Animation.fx.timer(tick)
}
//创建开始时间
function createFxNow() {
setTimeout(function() {
Animation.fxNow = undefined;
});
return (Animation.fxNow = Date.now());
}
//用于定时器调用
Animation.timers =[]
Animation.fx = {
//开始动画队列
timer: function(timer) {
Animation.timers.push(timer);
if (timer()) {
//开始执行动画
Animation.fx.start();
} else {
Animation.timers.pop();
}
},
//开始循环
start: function() {
if (!Animation.timerId) {
Animation.timerId = setInterval(Animation.fx.tick, 13);
}
},
//停止循环
stop:function(){
clearInterval(Animation.timerId);
Animation.timerId = null;
},
//循环的的检测
tick: function() {
var timer,
i = 0,
timers = Animation.timers;
Animation.fxNow = Date.now();
for (; i < timers.length; i++) {
timer = timers[i];
if (!timer() && timers[i] === timer) {
//如果完成了就删除这个动画
timers.splice(i--, 1);
}
}
if (!timers.length) {
Animation.fx.stop();
}
Animation.fxNow = undefined;
}
}
$("#one").click(function(){
Animation(book, {
left: '50'
}, {
duration: 2000
})
});
$("#two").click(function() {
Animation(book, {
left: '500'
}, {
duration: 2000
})
});
</script>
</body>
</html>
