jquery 圆形进度条

最近手里面的项目需要完成这个对设备性能的检测显示功能，需要使用到圆形进度条这样的效果，网上找了一圈，有很多相当的插件，找到：circliful 插件，看了他的使用说明比较的方便，于是就下载了它并将自己想要的效果添加了进去；

上面的效果，需要圆心中间的数字动态展示，并且在颜色值在小于50的时候为绿色，大于50的时候为红色；

第一步：页面布局

 <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
 <html xmlns="http://www.w3.org/1999/xhtml">
 <head>
 <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
 <title>圆形进度条</title>
 <link rel="icon" href="images/50.gif" rel="external nofollow"  type="image/gif" />
 <script src="js/jquery.min.js"></script>
 <script src="js/jquery.circliful.js"></script>
 <style>
     body{ margin:0; padding:0; font-size:14px; line-height:24px; color:#8b8b8b; font-family:Microsoft YaHei, Arial, Helvetica, sans-serif;}
     .you{ margin-left:36px; float:left; height:auto; width:55%; min-width:500px}
     .yous{ box-shadow:0px 0px 5px  #ddd; background:#FFF;}
     .youz{ background:url(./images/tbg.png) repeat-x; height:39px; line-height:39px; font-size:14px; color:#323436; text-indent:20px}
     .rrlh{ height:180px; margin-top:20px}
     .txz{ position: absolute; left: 50%; top: 50%; margin-left: -30px; margin-top: -30px; line-height: 30px;}
     .cpu{ width:50%; height:170px; float:left; text-align:center; position:relative}
 </style>
 </head>
 <div class="you">
     <div class="yous">
         <div class="youz">运行状态</div>
         <div class="rrlh">
             <!-- cpu使用率 -->
             <div class="cpu">
                 <div class="txz"><span style="font-size: 40px;" id="cpuText">0</span><br /> CPU使用率</div>
                 <div id="myStat2" style="display: inline-block" data-width="10" data-fontsize="28" ></div>
             </div>
             <!-- 内存使用率 -->
             <div class="cpu">
                 <div class="txz"><span style="font-size: 40px;" id="ncText">0</span><br /> 内存使用率</div>
                 <div id="myStat3" style="display: inline-block" data-width="10" data-fontsize="28" ></div>
             </div>
         </div>
     </div>
 </div>
 </html>

第二步：修改 jquery.circliful.js

 (function( $ ) {
     $.fn.circliful = function(options) {
         var settings = $.extend({
             // These are the defaults.
             foregroundColor: "#556b2f",
             backgroundColor: "#eee",
             fillColor: false,
             width: 15,
             dimension: 200,
             size: 15,
             percent: 50,
             endPercent: 100,
             showValue: "showValue", //新增 动态数值变化值显示标签ID
             animationStep: 1.0
         }, options );
          return this.each(function() {
                 var dimension = '';
                 var text = '';
                 var info = '';
                 var width = '';
                 var size = 0;
                 var percent = 0;
                 var endPercent = 100;
                 var fgcolor = '';
                 var bgcolor = '';
                 var icon = '';
                 var animationstep = 0.0;
                 var showValue = '';
                 $(this).addClass('circliful');                 showValue = settings.showValue; //赋值                 if($(this).data('dimension') != undefined) {
                     dimension = $(this).data('dimension');
                 } else {
                     dimension = settings.dimension;
                 }                 if($(this).data('width') != undefined) {
                     width = $(this).data('width');
                 } else {
                     width = settings.width;
                 }                 if($(this).data('fontsize') != undefined) {
                     size = $(this).data('fontsize');
                 } else {
                     size = settings.size;
                 }                 if($(this).data('percent') != undefined) {
                     percent = $(this).data('percent') / 100;
                     endPercent = $(this).data('percent');
                 } else {
                     percent = settings.percent / 100;
                     endPercent = settings.endPercent;
                 }                 if($(this).data('fgcolor') != undefined) {
                     fgcolor = $(this).data('fgcolor');
                 } else {
                     fgcolor = settings.foregroundColor;
                 }                 if($(this).data('bgcolor') != undefined) {
                     bgcolor = $(this).data('bgcolor');
                 } else {
                     bgcolor = settings.backgroundColor;
                 }                 if($(this).data('animation-step') != undefined) {
                     animationstep = parseFloat($(this).data('animation-step'));
                 } else {
                     animationstep = settings.animationStep;
                 }
                 if($(this).data('text') != undefined) {
                     text = $(this).data('text');                     if($(this).data('icon') != undefined) {
                         icon = '<i class="fa ' + $(this).data('icon') + '"></i>';
                     }                      if($(this).data('type') != undefined) {
                         type = $(this).data('type');                         if(type == 'half') {
                             $(this).append('<span class="circle-text-half">' +  icon  + text + '</span>');
                             $(this).find('.circle-text-half').css({'line-height': (dimension / 1.45) + 'px', 'font-size' : size + 'px' });
                         } else {
                             $(this).append('<span class="circle-text">' + icon + text + '</span>');
                             //设置文字样式
                             $(this).find('.circle-text').css(
                                 {'line-height': dimension + 'px', 'font-size' : size + 'px'}
                             );
                         }
                     } else {
                         $(this).append('<span class="circle-text">' + icon + text + '</span>');
                         $(this).find('.circle-text').css(
                             {'line-height': dimension + 'px', 'font-size' : size + 'px' }
                         );
                     }
                 } else if($(this).data('icon') != undefined) {                 }                 if($(this).data('info') != undefined) {
                     info = $(this).data('info');                     if($(this).data('type') != undefined) {
                         type = $(this).data('type');                         if(type == 'half') {
                             $(this).append('<span class="circle-info-half">' + info + '</span>');
                             $(this).find('.circle-info-half').css({'line-height': (dimension * 0.9) + 'px', });
                         } else {
                             $(this).append('<span class="circle-info">' + info + '</span>');
                             $(this).find('.circle-info').css({'line-height': (dimension * 1.25) + 'px', });
                         }
                     } else {
                         $(this).append('<span class="circle-info">' + info + '</span>');
                         $(this).find('.circle-info').css({'line-height': (dimension * 1.25) + 'px', });
                     }
                 }                 $(this).width(dimension + 'px');               var canvas = $('<canvas></canvas>').attr({ width: dimension, height: dimension }).appendTo($(this)).get(0);
               var context = canvas.getContext('2d');
               var x = canvas.width / 2;
               var y = canvas.height / 2;
               var degrees = percent * 360.0;
               var radians = degrees * (Math.PI / 180);
               var radius = canvas.width / 2.5;
               var startAngle = 2.3 * Math.PI;
               var endAngle = 0;
               var counterClockwise = false;
               var curPerc = animationstep === 0.0 ? endPercent : 0.0;
               var curStep = Math.max(animationstep, 0.0);
               var circ = Math.PI * 2;
               var quart = Math.PI / 2;
               var type = '';
               var fill = false;               if($(this).data('type') != undefined) {
                     type = $(this).data('type');                     if(type == 'half') {
                         var startAngle = 2.0 * Math.PI;
                         var endAngle = 3.13;
                         var circ = Math.PI * 1.0;
                         var quart = Math.PI / 0.996;
                     }
                 }                 if($(this).data('fill') != undefined) {
                     fill = $(this).data('fill');
                 } else {
                     fill = settings.fillColor;
                 }
               //animate foreground circle
               function animate(current) {
                 /**
                  * [修改] 设置圆心动态数据变化值
                  * showValue 为显示动态值的html标签的ID
                  * 这里 parseInt(current*100) 取整数，他的最大值为 endPercent的值
                  **/
                 $("#"+showValue).html(parseInt(current*100));
                 /**
                  * [修改] 判断值是否超过圆形的一半，并修改圆形颜色              *
                  **/
                 if(current <.5){
                     fgcolor = '#14b997';
                 }else{
                     fgcolor = '#f75656';
                 }                 context.clearRect(0, 0, canvas.width, canvas.height);
                 context.beginPath();
                 context.arc(x, y, radius, endAngle, startAngle, false);
                 context.lineWidth = width - 1;
                 // line color
                 context.strokeStyle = bgcolor;
                 context.stroke();
                 if(fill) {
                     context.fillStyle = fill;
                     context.fill();
                 }
                 context.beginPath();
                 context.arc(x, y, radius, -(quart), ((circ) * current) - quart, false);
                 context.lineWidth = width;
                 // line color
                 context.strokeStyle = fgcolor;
                 context.stroke();                 if (curPerc < endPercent) {
                        curPerc += curStep;
                      requestAnimationFrame(function () {
                         /**
                          * [修改] 降低圆形进度条速度
                          **/
                         setTimeout(function(){
                             animate(Math.min(curPerc, endPercent) / 100);
                         }, 40);
                      });
                 }
              }
              animate(curPerc / 100);
         });
     };
 }( jQuery ));

第三步：调用

 $(document).ready(function(){
         var cupCount = 10,
             ncCount = 80;
         var myStat2Color = cupCount > 50 ? '#f75656' : '#14b997';
         var myStat3Color = ncCount > 50 ? '#f75656' : '#14b997';
         $('#myStat2').circliful({
             dimension: 170,
             endPercent: cupCount,
             showValue: "cpuText",
             foregroundColor: myStat2Color,//556b2f
             backgroundColor: "#eee",
         });
         $('#myStat3').circliful({
             dimension: 170,
             endPercent: ncCount,
             showValue: "ncText",
             foregroundColor: myStat3Color,
             backgroundColor: "#eee",
         });
     });