这是一款基于HTML5和JavaScript的进度条应用，这款进度条插件非常有特点，它在进度展示的时候呈现粒子的动画效果，也就是说，进度条在滑动的同时，会产生一些小粒子掉落下来，效果非常酷。另外还有一个特点是随着进度的变化，进度条的颜色也会变化。

JavaScript代码

/*========================================================*/ 
/* Light Loader
/*========================================================*/
var lightLoader = function(c, cw, ch){
 var _this = this;
 this.c = c;
 this.ctx = c.getContext('2d');
 this.cw = cw;
 this.ch = ch; 
 this.loaded = 0;
 this.loaderSpeed = .6;
 this.loaderHeight = 10;
 this.loaderWidth = 310; 
 this.loader = {
 x: (this.cw/2) - (this.loaderWidth/2),
 y: (this.ch/2) - (this.loaderHeight/2)
 };
 this.particles = [];
 this.particleLift = 180;
 this.hueStart = 0
 this.hueEnd = 120;
 this.hue = 0;
 this.gravity = .15;
 this.particleRate = 4; 
 /*========================================================*/ 
 /* Initialize
 /*========================================================*/
 this.init = function(){
 this.loop();
 };
 /*========================================================*/ 
 /* Utility Functions
 /*========================================================*/ 
 this.rand = function(rMi, rMa){return ~~((Math.random()*(rMa-rMi+1))+rMi);};
 this.hitTest = function(x1, y1, w1, h1, x2, y2, w2, h2){return !(x1 + w1 < x2 || x2 + w2 < x1 || y1 + h1 < y2 || y2 + h2 < y1);};
 /*========================================================*/ 
 /* Update Loader
 /*========================================================*/
 this.updateLoader = function(){
 if(this.loaded < 100){
 this.loaded += this.loaderSpeed;
 } else {
 this.loaded = 0;
 }
 };
 /*========================================================*/ 
 /* Render Loader
 /*========================================================*/
 this.renderLoader = function(){
 this.ctx.fillStyle = '#000';
 this.ctx.fillRect(this.loader.x, this.loader.y, this.loaderWidth, this.loaderHeight);
 this.hue = this.hueStart + (this.loaded/100)*(this.hueEnd - this.hueStart);
 var newWidth = (this.loaded/100)*this.loaderWidth;
 this.ctx.fillStyle = 'hsla('+this.hue+', 100%, 40%, 1)';
 this.ctx.fillRect(this.loader.x, this.loader.y, newWidth, this.loaderHeight);
 this.ctx.fillStyle = '#222';
 this.ctx.fillRect(this.loader.x, this.loader.y, newWidth, this.loaderHeight/2);
 }; 
 /*========================================================*/ 
 /* Particles
 /*========================================================*/
 this.Particle = function(){ 
 this.x = _this.loader.x + ((_this.loaded/100)*_this.loaderWidth) - _this.rand(0, 1);
 this.y = _this.ch/2 + _this.rand(0,_this.loaderHeight)-_this.loaderHeight/2;
 this.vx = (_this.rand(0,4)-2)/100;
 this.vy = (_this.rand(0,_this.particleLift)-_this.particleLift*2)/100;
 this.width = _this.rand(1,4)/2;
 this.height = _this.rand(1,4)/2;
 this.hue = _this.hue;
 };
 this.Particle.prototype.update = function(i){
 this.vx += (_this.rand(0,6)-3)/100; 
 this.vy += _this.gravity;
 this.x += this.vx;
 this.y += this.vy;
 if(this.y > _this.ch){
 _this.particles.splice(i, 1);
 } 
 };
 this.Particle.prototype.render = function(){
 _this.ctx.fillStyle = 'hsla('+this.hue+', 100%, '+_this.rand(50,70)+'%, '+_this.rand(20,100)/100+')';
 _this.ctx.fillRect(this.x, this.y, this.width, this.height);
 };
 this.createParticles = function(){
 var i = this.particleRate;
 while(i--){
 this.particles.push(new this.Particle());
 };
 };
 this.updateParticles = function(){ 
 var i = this.particles.length; 
 while(i--){
 var p = this.particles[i];
 p.update(i); 
 }; 
 };
 this.renderParticles = function(){
 var i = this.particles.length; 
 while(i--){
 var p = this.particles[i];
 p.render(); 
 }; 
 };
 /*========================================================*/ 
 /* Clear Canvas
 /*========================================================*/
 this.clearCanvas = function(){
 this.ctx.globalCompositeOperation = 'source-over';
 this.ctx.clearRect(0,0,this.cw,this.ch); 
 this.ctx.globalCompositeOperation = 'lighter';
 };
 /*========================================================*/ 
 /* Animation Loop
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 this.loop = function(){
 var loopIt = function(){
 requestAnimationFrame(loopIt, _this.c);
 _this.clearCanvas();
 _this.createParticles();
 _this.updateLoader();
 _this.updateParticles();
 _this.renderLoader();
 _this.renderParticles();
 };
 loopIt(); 
 };
};
/*========================================================*/ 
/* Check Canvas Support
/*========================================================*/
var isCanvasSupported = function(){
 var elem = document.createElement('canvas');
 return !!(elem.getContext && elem.getContext('2d'));
};
/*========================================================*/ 
/* Setup requestAnimationFrame
/*========================================================*/
var setupRAF = function(){
 var lastTime = 0;
 var vendors = ['ms', 'moz', 'webkit', 'o'];
 for(var x = 0; x < vendors.length && !window.requestAnimationFrame; ++x){
 window.requestAnimationFrame = window[vendors[x]+'RequestAnimationFrame'];
 window.cancelAnimationFrame = window[vendors[x]+'CancelAnimationFrame'] || window[vendors[x]+'CancelRequestAnimationFrame'];
 };
 if(!window.requestAnimationFrame){
 window.requestAnimationFrame = function(callback, element){
 var currTime = new Date().getTime();
 var timeToCall = Math.max(0, 16 - (currTime - lastTime));
 var id = window.setTimeout(function() { callback(currTime + timeToCall); }, timeToCall);
 lastTime = currTime + timeToCall;
 return id;
 };
 };
 if (!window.cancelAnimationFrame){
 window.cancelAnimationFrame = function(id){
 clearTimeout(id);
 };
 };
}; 
/*========================================================*/ 
/* Define Canvas and Initialize
/*========================================================*/
if(isCanvasSupported){
 var c = document.createElement('canvas');
 c.width = 400;
 c.height = 100; 
 var cw = c.width;
 var ch = c.height; 
 document.body.appendChild(c); 
 var cl = new lightLoader(c, cw, ch); 
 setupRAF();
 cl.init();
}