ichart.js绘制虚线、平均分虚线效果的实现代码

var Data=new Array();     Data[0] = {       labels : ["第一单元","第二单元","第三单元","第四单元","第五单元"],       datasets : [         {           name : '优秀率',           color:'#1dbcfe',           line_width:4,           value : [80,75,92,62,0]         }       ]     }     Data[1] = {       labels : ["第一单元","第二单元","第三单元","第四单元","第五单元"],       datasets : [         {           name : '优秀率',           color:'#1dbcfe',           line_width:4,           value : [50,11,62,77,90]         }       ]     }     Data[2] = {       labels : ["第一单元","第二单元","第三单元","第四单元","第五单元"],       datasets : [         {           name : '优秀率',           color:'#1dbcfe',           line_width:4,           value : [80,51,32,44,80]         }       ]     }          var _bodyWidth=$('body').width()-16;     $('.item').each(function(i){       var _id=$(this).find('.canvas-wrap').attr('id');       var chart = new iChart.LineBasic2D({         render : _id,         data: Data[i].datasets,         align:'center',         border:0,         width : _bodyWidth*2,         height : _bodyWidth*1.2,         background_color:'#fafafa',         animation : true,//开启过渡动画         animation_duration:600,//600ms完成动画                  sub_option : {           smooth : true,           hollow:false,           hollow_inside:false,           point_size:16,           listeners : {             parseText : function(r, t) {               return t+'%';             }           },           label:{fontsize:24,color:'#333'},         },         coordinate:{           width:_bodyWidth*1.6,           valid_width:_bodyWidth*1.4,           height:_bodyWidth*1.6*.5,           striped_factor : 0.18,           axis:{             color:'#aaa',             width:[0,0,8,0]           },           scale:[{              position:'left',               start_scale:0,              end_scale:100,              scale_space:20,              scale_size:2,              scale_enable : false,              label : {color:'#999',fontsize:24},              scale_color:'#999'          },{              position:'bottom',              label : {color:'#999',fontsize:24},              scale_enable : false,              labels:Data[i].labels           }]         }                });       /**        *自定义组件,画平均线。        */      chart.plugin(new iChart.Custom({           drawFn:function(){             /**              *计算平均值的高度(坐标Y值)              */              var _total=0;             $.each(Data[i].datasets[0].value,function(i,val){               _total+=val;             });             var avg = _total/Data[i].datasets[0].value.length,//计算出的平均分写在这即可               coo = chart.getCoordinate(),               x = coo.get('originx'),               W = coo.width,               S = coo.getScale('left'),               H = coo.height,               h = (avg - S.start) * H / S.distance,               y = chart.y + H - h;             for(xi=x;xi<=(x+W);xi=xi+32){               chart.target.line(xi,y,xi+16,y,2,'#fe941c');             }             chart.target.textAlign('start')             .textBaseline('middle')             .textFont('500 20px Verdana')             .fillText('平均战胜率'+avg+'%',x+W-100,y-20,false,'#fe941c');           }       }));       chart.draw();     });