Backend API
        
    import React from 'react';
import PieChart, {
  Series,
  Legend,
  Label,
  Connector,
} from 'devextreme-react/pie-chart';
import { data } from './data.ts';
import CenterTemplate from './CenterTemplate.tsx';
const countries = Array.from(new Set(data.map((item) => item.country)));
const customizeLabel = (e) => `${e.argumentText}\n${e.valueText}`;
function App() {
  const pies = countries.map((country) => (
    <PieChart
      id="pie-chart"
      key={country}
      dataSource={data.filter((i) => i.country === country)}
      resolveLabelOverlapping="shift"
      sizeGroup="piesGroup"
      innerRadius={0.65}
      centerRender={CenterTemplate}
      type="doughnut"
    >
      <Series
        argumentField="commodity"
        valueField="total"
      >
        <Label visible={true}
          format="fixedPoint"
          customizeText={customizeLabel}
          backgroundColor="none">
          <Connector visible={true}></Connector>
        </Label>
      </Series>
      <Legend visible={false}></Legend>
    </PieChart>
  ));
  return (
    <div>
      <div className="long-title"><h3>Energy Production (GWh, 2016)</h3></div>
      <div className="pies-container">
        {pies}
      </div>
    </div>
  );
}
export default App;
    
    import React from 'react';
import PieChart, {
  Series, Legend, Label, Connector,
} from 'devextreme-react/pie-chart';
import { data } from './data.js';
import CenterTemplate from './CenterTemplate.js';
const countries = Array.from(new Set(data.map((item) => item.country)));
const customizeLabel = (e) => `${e.argumentText}\n${e.valueText}`;
function App() {
  const pies = countries.map((country) => (
    <PieChart
      id="pie-chart"
      key={country}
      dataSource={data.filter((i) => i.country === country)}
      resolveLabelOverlapping="shift"
      sizeGroup="piesGroup"
      innerRadius={0.65}
      centerRender={CenterTemplate}
      type="doughnut"
    >
      <Series
        argumentField="commodity"
        valueField="total"
      >
        <Label
          visible={true}
          format="fixedPoint"
          customizeText={customizeLabel}
          backgroundColor="none"
        >
          <Connector visible={true}></Connector>
        </Label>
      </Series>
      <Legend visible={false}></Legend>
    </PieChart>
  ));
  return (
    <div>
      <div className="long-title">
        <h3>Energy Production (GWh, 2016)</h3>
      </div>
      <div className="pies-container">{pies}</div>
    </div>
  );
}
export default App;
    
    import { PieChartRef } from 'devextreme-react/pie-chart';
import React from 'react';
const formatNumber = new Intl.NumberFormat('en-US', {
  minimumFractionDigits: 0,
}).format;
function calculateTotal(pieChart: ReturnType<PieChartRef['instance']>) {
  return formatNumber(pieChart
    .getAllSeries()[0]
    .getVisiblePoints()
    .reduce((s, p) => s + Number(p.originalValue), 0));
}
function getImagePath(country: string) {
  return `../../../../images/flags/${country.replace(/\s/, '').toLowerCase()}.svg`;
}
export default function TooltipTemplate(pieChart: ReturnType<PieChartRef['instance']>) {
  const { country } = pieChart.getAllSeries()[0].getVisiblePoints()[0].data;
  return (
    <svg>
      <circle cx="100" cy="100" r={pieChart.getInnerRadius() - 6} fill="#eee"></circle>
      <image href={getImagePath(country)} x="70" y="58" width="60" height="40" />
      <text textAnchor="middle" x="100" y="120" style={{ fontSize: 18, fill: '#494949' }}>
        <tspan x="100">{country}</tspan>
        <tspan x="100" dy="20px" style={{ fontWeight: 600 }}>{
          calculateTotal(pieChart)
        }</tspan>
      </text>
    </svg>
  );
}
    
    import React from 'react';
import ReactDOM from 'react-dom';
import App from './App.tsx';
ReactDOM.render(
  <App />,
  document.getElementById('app'),
);
    
    export const data = [
  { country: 'France', commodity: 'Nuclear', total: 413278 },
  { country: 'Germany', commodity: 'Nuclear', total: 76536 },
  { country: 'France', commodity: 'Thermal', total: 47594 },
  { country: 'Germany', commodity: 'Thermal', total: 375809 },
  { country: 'France', commodity: 'Wind', total: 21033 },
  { country: 'Germany', commodity: 'Wind', total: 58228 },
  { country: 'France', commodity: 'Solar', total: 7274 },
  { country: 'Germany', commodity: 'Solar', total: 37520 },
  { country: 'France', commodity: 'Tidal, Wave', total: 618 },
];
    
    window.exports = window.exports || {};
window.config = {
  transpiler: 'ts',
  typescriptOptions: {
    module: 'system',
    emitDecoratorMetadata: true,
    experimentalDecorators: true,
    jsx: 'react',
  },
  meta: {
    'react': {
      'esModule': true,
    },
    'typescript': {
      'exports': 'ts',
    },
    'devextreme/time_zone_utils.js': {
      'esModule': true,
    },
    'devextreme/localization.js': {
      'esModule': true,
    },
    'devextreme/viz/palette.js': {
      'esModule': true,
    },
    'openai': {
      'esModule': true,
    },
  },
  paths: {
    'npm:': 'https://cdn.jsdelivr.net/npm/',
    'bundles:': '../../../../bundles/',
    'externals:': '../../../../bundles/externals/',
  },
  defaultExtension: 'js',
  map: {
    'ts': 'npm:plugin-typescript@8.0.0/lib/plugin.js',
    'typescript': 'npm:typescript@4.2.4/lib/typescript.js',
    'jszip': 'npm:jszip@3.10.1/dist/jszip.min.js',
    'react': 'npm:react@17.0.2/umd/react.development.js',
    'react-dom': 'npm:react-dom@17.0.2/umd/react-dom.development.js',
    'prop-types': 'npm:prop-types/prop-types.js',
    'rrule': 'npm:rrule@2.6.4/dist/es5/rrule.js',
    'luxon': 'npm:luxon@3.4.4/build/global/luxon.min.js',
    'es6-object-assign': 'npm:es6-object-assign',
    'devextreme': 'npm:devextreme@link:../../packages/devextreme/artifacts/npm/devextreme/cjs',
    'devextreme-react': 'npm:devextreme-react@link:../../packages/devextreme-react/npm/cjs',
    'devextreme-quill': 'npm:devextreme-quill@1.7.6/dist/dx-quill.min.js',
    'devexpress-diagram': 'npm:devexpress-diagram@2.2.24/dist/dx-diagram.js',
    'devexpress-gantt': 'npm:devexpress-gantt@4.1.64/dist/dx-gantt.js',
    'inferno': 'npm:inferno@8.2.3/dist/inferno.min.js',
    'inferno-compat': 'npm:inferno-compat/dist/inferno-compat.min.js',
    'inferno-create-element': 'npm:inferno-create-element@8.2.3/dist/inferno-create-element.min.js',
    'inferno-dom': 'npm:inferno-dom/dist/inferno-dom.min.js',
    'inferno-hydrate': 'npm:inferno-hydrate/dist/inferno-hydrate.min.js',
    'inferno-clone-vnode': 'npm:inferno-clone-vnode/dist/inferno-clone-vnode.min.js',
    'inferno-create-class': 'npm:inferno-create-class/dist/inferno-create-class.min.js',
    'inferno-extras': 'npm:inferno-extras/dist/inferno-extras.min.js',
    '@preact/signals-core': 'npm:@preact/signals-core@1.8.0/dist/signals-core.min.js',
    'devextreme-cldr-data': 'npm:devextreme-cldr-data@1.0.3',
    // SystemJS plugins
    'plugin-babel': 'npm:systemjs-plugin-babel@0.0.25/plugin-babel.js',
    'systemjs-babel-build': 'npm:systemjs-plugin-babel@0.0.25/systemjs-babel-browser.js',
    // Prettier
    'prettier/standalone': 'npm:prettier@2.8.8/standalone.js',
    'prettier/parser-html': 'npm:prettier@2.8.8/parser-html.js',
  },
  packages: {
    'devextreme': {
      defaultExtension: 'js',
    },
    'devextreme-react': {
      main: 'index.js',
    },
    'devextreme-react/common': {
      main: 'index.js',
    },
    'devextreme/events/utils': {
      main: 'index',
    },
    'devextreme/common/core/events/utils': {
      main: 'index',
    },
    'devextreme/localization/messages': {
      format: 'json',
      defaultExtension: 'json',
    },
    'devextreme/events': {
      main: 'index',
    },
    'es6-object-assign': {
      main: './index.js',
      defaultExtension: 'js',
    },
  },
  packageConfigPaths: [
    'npm:@devextreme/*/package.json',
  ],
  babelOptions: {
    sourceMaps: false,
    stage0: true,
    react: true,
  },
};
System.config(window.config);
// eslint-disable-next-line
const useTgzInCSB = ['openai'];
    
    import React from 'react';
const formatNumber = new Intl.NumberFormat('en-US', {
  minimumFractionDigits: 0,
}).format;
function calculateTotal(pieChart) {
  return formatNumber(
    pieChart
      .getAllSeries()[0]
      .getVisiblePoints()
      .reduce((s, p) => s + Number(p.originalValue), 0),
  );
}
function getImagePath(country) {
  return `../../../../images/flags/${country.replace(/\s/, '').toLowerCase()}.svg`;
}
export default function TooltipTemplate(pieChart) {
  const { country } = pieChart.getAllSeries()[0].getVisiblePoints()[0].data;
  return (
    <svg>
      <circle
        cx="100"
        cy="100"
        r={pieChart.getInnerRadius() - 6}
        fill="#eee"
      ></circle>
      <image
        href={getImagePath(country)}
        x="70"
        y="58"
        width="60"
        height="40"
      />
      <text
        textAnchor="middle"
        x="100"
        y="120"
        style={{ fontSize: 18, fill: '#494949' }}
      >
        <tspan x="100">{country}</tspan>
        <tspan
          x="100"
          dy="20px"
          style={{ fontWeight: 600 }}
        >
          {calculateTotal(pieChart)}
        </tspan>
      </text>
    </svg>
  );
}
    
    import React from 'react';
import ReactDOM from 'react-dom';
import App from './App.js';
ReactDOM.render(<App />, document.getElementById('app'));
    
    export const data = [
  { country: 'France', commodity: 'Nuclear', total: 413278 },
  { country: 'Germany', commodity: 'Nuclear', total: 76536 },
  { country: 'France', commodity: 'Thermal', total: 47594 },
  { country: 'Germany', commodity: 'Thermal', total: 375809 },
  { country: 'France', commodity: 'Wind', total: 21033 },
  { country: 'Germany', commodity: 'Wind', total: 58228 },
  { country: 'France', commodity: 'Solar', total: 7274 },
  { country: 'Germany', commodity: 'Solar', total: 37520 },
  { country: 'France', commodity: 'Tidal, Wave', total: 618 },
];
    
    <!DOCTYPE html>
<html lang="en">
  <head>
    <title>DevExtreme Demo</title>
    <meta http-equiv="X-UA-Compatible" content="IE=edge" />
    <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=5.0" />
    <link rel="stylesheet" type="text/css" href="https://cdn3.devexpress.com/jslib/25.1.6/css/dx.light.css" />
    <link rel="stylesheet" type="text/css" href="styles.css" />
    <script src="https://cdn.jsdelivr.net/npm/core-js@2.6.12/client/shim.min.js"></script>
    <script src="https://cdn.jsdelivr.net/npm/systemjs@0.21.3/dist/system.js"></script>
    <script type="text/javascript" src="config.js"></script>
    <script type="text/javascript">
      System.import("./index.tsx");
    </script>
  </head>
  <body class="dx-viewport">
    <div class="demo-container">
      <div id="app"></div>
    </div>
  </body>
</html>
    
    .pies-container {
  margin: auto;
  width: 800px;
}
.pies-container > div {
  width: 400px;
  float: left;
  margin-top: -50px;
}
.long-title h3 {
  font-weight: 200;
  font-size: 28px;
  text-align: center;
  margin-bottom: 20px;
}
.dxc-hole-template:focus {
  outline: none;
}