把下面代码的数据换成后台接口的动态数据给出修改后的代码import as echarts from componentsec-canvasechartsfunction initChartcanvas width height dpr const chart = echartsinitcanvas null width width height height device

import * as echarts from '../../components/ec-canvas/echarts'

function initChart(canvas, width, height, dpr) { const chart = echarts.init(canvas, null, { width: width, height: height, devicePixelRatio: dpr }); canvas.setChart(chart);

wx.request({ url: '后台接口的URL', method: 'GET', success: function(res) { var data = res.data; // 后台返回的动态数据

  var option = {
    backgroundColor: "#ffffff",
    series: [{
      label: {
        normal: {
          fontSize: 14
        }
      },
      type: 'pie',
      center: ['50%', '50%'],
      radius: ['20%', '40%'],
      data: data // 使用后台返回的数据
    }]
  };
  chart.setOption(option);
}

});

return chart; }

Page({ data: { ec: { onInit: initChart } } }