React Charts - Custom Legend Markers

import React from 'react';

import {

  Chart, Series, CommonSeriesSettings, Point, Legend,

} from 'devextreme-react/chart';

import { dataSource } from './data.js';

import markerTemplate from './MarkerTemplate.js';

​

function onLegendClick(e) {

  e.target.isVisible() ? e.target.hide() : e.target.show();

}

function App() {

  return (

    <Chart

      id="chart"

      title="Noisy and Original Signals"

      dataSource={dataSource}

      onLegendClick={onLegendClick}

    >

      <CommonSeriesSettings argumentField="argument">

        <Point visible={false}></Point>

      </CommonSeriesSettings>

      <Series

        valueField="originalValue"

        name="Original Signal"

      />

      <Series

        valueField="value"

        name="Noisy Signal"

      />

      <Legend

        verticalAlignment="bottom"

        horizontalAlignment="center"

        markerRender={markerTemplate}

      ></Legend>

    </Chart>

  );

}

export default App;

​

import React from 'react';

​

const markerPath = {

  'Original Signal': 'M 0 8 C 2 4 7 4 9.5 8 C 11 12 16 12 18 8 L 18 10 C 16 14 11 14 8.5 10 C 7 6 2 6 0 10 Z',

  'Noisy Signal': 'M 18 8 L 12 12 L 7 3 L 0 7.4 L 0 10 L 6 6 L 11 15 L 18 10.6 Z',

};

​

export default function MarkerTemplate(item) {

  const color = item.series.isVisible() ? item.marker.fill : '#888';

  return (

    <svg>

      <rect x={0} y={0} width={18} height={18} fill={color} opacity={0.3}></rect>

      <path d={markerPath[item.series.name]} fill={color}></path>

    </svg>

  );

}

​

import React from 'react';

import ReactDOM from 'react-dom';

​

import App from './App.tsx';

​

ReactDOM.render(

  <App />,

  document.getElementById('app'),

);

​

function generateData(start: number, end: number, step: number) {

  const data: ({ value: number; originalValue: number; argument: number; })[] = [];

  for (let i = start; i < end; i += step) {

    const originalValue = Math.sin(i) / i;

    data.push({ value: originalValue + ((0.5 - Math.random()) / 10), originalValue, argument: i });

  }

  return data;

}

​

export const dataSource = generateData(2.5, 12, 0.1);

​

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://unpkg.com/',

    '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@24.2.6/cjs',

    'devextreme-react': 'npm:devextreme-react@24.2.6/cjs',

    'devextreme-quill': 'npm:devextreme-quill@1.7.1/dist/dx-quill.min.js',

    'devexpress-diagram': 'npm:devexpress-diagram@2.2.15/dist/dx-diagram.js',

    'devexpress-gantt': 'npm:devexpress-gantt@4.1.60/dist/dx-gantt.js',

    '@devextreme/runtime': 'npm:@devextreme/runtime@3.0.12',

    'inferno': 'npm:inferno@7.4.11/dist/inferno.min.js',

    'inferno-compat': 'npm:inferno-compat/dist/inferno-compat.min.js',

    'inferno-create-element': 'npm:inferno-create-element@7.4.11/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',

    '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/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',

    'npm:@devextreme/runtime@3.0.12/inferno/package.json',

  ],

  babelOptions: {

    sourceMaps: false,

    stage0: true,

    react: true,

  },

};

System.config(window.config);

​

import React from 'react';

​

const markerPath = {

  'Original Signal':

    'M 0 8 C 2 4 7 4 9.5 8 C 11 12 16 12 18 8 L 18 10 C 16 14 11 14 8.5 10 C 7 6 2 6 0 10 Z',

  'Noisy Signal': 'M 18 8 L 12 12 L 7 3 L 0 7.4 L 0 10 L 6 6 L 11 15 L 18 10.6 Z',

};

export default function MarkerTemplate(item) {

  const color = item.series.isVisible() ? item.marker.fill : '#888';

  return (

    <svg>

      <rect

        x={0}

        y={0}

        width={18}

        height={18}

        fill={color}

        opacity={0.3}

      ></rect>

      <path

        d={markerPath[item.series.name]}

        fill={color}

      ></path>

    </svg>

  );

}

​

import React from 'react';

import ReactDOM from 'react-dom';

import App from './App.js';

​

ReactDOM.render(<App />, document.getElementById('app'));

​

function generateData(start, end, step) {

  const data = [];

  for (let i = start; i < end; i += step) {

    const originalValue = Math.sin(i) / i;

    data.push({ value: originalValue + (0.5 - Math.random()) / 10, originalValue, argument: i });

  }

  return data;

}

export const dataSource = generateData(2.5, 12, 0.1);

​

<!DOCTYPE html>

<html lang="en">

  <head>↔</head>

​

  <body class="dx-viewport">

    <div class="demo-container">

      <div id="app"></div>

    </div>

  </body>

</html>

​

#chart {

  height: 440px;

}

​