jQuery动画的实现
没有引入deferred机制，其余流程都有了
//////////// //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; } }
测试：
