<!doctype html>
<html>
<head>
<meta charset='utf-8'>
<title>html5有特色的进度条</title>
<base target="_blank" />
<style>
body {
background: #111;
color:white;
}
a{color:white;}
canvas {
background: #111;
border: 1px solid #171717;
display: block;
left: 50%;
margin: -51px 0 0 -201px;
position: absolute;
top: 50%;
}
</style>
</head>
<body>
<script type="text/javascript">
/*==============================================*/
/* 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();
};
};</p>
<p>/*========================================================*/
/* 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
/*========================================================*/
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();
}
</script>
<div style="position:absolute; top: 0;width:100%">
<div class="footer-banner" style="width:728px;margin:10px auto;color:white">
html5进度条
请使用支持html5的浏览器查看本页</div>
</div>
</body>
</html>
我要评论
网友评论