extjs图形绘制之饼图实现方法分析

Ext.define('ChartPieTest', {
  extend: 'Ext.panel.Panel',
  autoScroll : true,
  initComponent: function () {
    var me = this;
    me.store = me.createStore();
    me.grid = me.getGridPanel();
    me.mainPanel = Ext.create('Ext.panel.Panel',{
      layout:'fit',
      items:[me.grid],
    });
 
    Ext.apply(me,{
      layout:'fit',
      items:[me.mainPanel]
    });
    me.callParent();
    me.mainPanel.down('chart').on('cellclick', function(grid, td, cellIndex, record, tr, rowIndex, e, eOpts) {
      me.onCellClick(cellIndex, record);
    });
  },
 
  getGridPanel:function(){
    var me = this;
    return {
      xtype:'chart',
      insetPadding: 40,
      animate : true,// 是否支持动态数据变化
      legend: {// 图例
        position: "right",
        spacing: 12,
        padding: 5,
        font: {
          name: 'Tahoma',
          color: '#3366FF',
          size: 12,
          bold: true
        }
      },
      store:me.store,
      //axes:me.createAxes(),
      series:me.createSeries(),
    }
  },
  createStore: function () {
    var me = this;
    return Ext.create('Ext.data.JsonStore', {
      //从后端请求数据
     /* fields: [
        {name: 'id', mapping: 'id'},
        {name:'statTime',mapping:'statTime',type:'date',dateFormat:'time'},
        'activeCount', 'effectiveCount','effectiveProportion',
      ],
      proxy: {
        type: 'ajax',
        url: ctx+'/mvc//analyze/tblVwMonthUserStat',
        reader: {
          type: 'json',
          root: 'root',
          totalProperty: 'totalProperty'
        }
      },
      listeners: {
        'beforeload': function (store, operation, eOpts) {
          store.proxy.extraParams.selectYear = me.selectYear
        }
      },*/
     //自己模拟数据
      fields: ['name', 'data'],
      data: [
        { 'name': '中年人',  'data': 10 },
        { 'name': '婴儿',  'data': 7 },
        { 'name': '老年人', 'data': 5 },
        { 'name': '小孩', 'data': 2 },
        { 'name': '青少年', 'data': 27 }
      ],
      autoLoad: true
    });
  },
  
  createSeries: function () {
    var me = this;
    var columns = [
      {
        type: 'pie',
        angleField: 'data',
        showInLegend: true,
        tips: {
          trackMouse: true,
          width: 140,
          height: 40,
          renderer: function(storeItem, item) {
            // calculate and display percentage on hover
            var total = 0;
            me.store.each(function(rec) {
              total += rec.get('data');
            });
            this.setTitle(storeItem.get('name') + ': ' + Math.round(storeItem.get('data') / total * 100) + '%');
          }
        },
        highlight: {
          segment: {
            margin: 5
          }
        },
        label: {
          field: 'name',
          display: 'rotate',
          contrast: true,
          font: '18px Arial'
        }
      },
 
    ];
    return columns;
  }
 
});