Custom Legend Markers
Legend markers are SVG elements. To customize a legend marker, declare the SVG markup in the markerTemplate. You can access the legend item data object inside the template and use it to identify the series and read its parameters.
In this demo, the markers' appearance changes when you click the markers to show or hide the corresponding series.
Feel free to share demo-related thoughts here.
If you have technical questions, please create a support ticket in the DevExpress Support Center.
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If you have technical questions, please create a support ticket in the DevExpress Support Center.
Backend API
import React from 'react';
import {
Chart, ChartTypes, Series, CommonSeriesSettings, Point, Legend,
} from 'devextreme-react/chart';
import { dataSource } from './data.ts';
import markerTemplate from './MarkerTemplate.tsx';
function onLegendClick(e: ChartTypes.LegendClickEvent) {
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';
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,
},
},
paths: {
'npm:': 'https://unpkg.com/',
},
defaultExtension: 'js',
map: {
'ts': 'npm:plugin-typescript@4.2.4/lib/plugin.js',
'typescript': 'npm:typescript@4.2.4/lib/typescript.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@15.8.1/prop-types.js',
'rrule': 'npm:rrule@2.6.4/dist/es5/rrule.js',
'luxon': 'npm:luxon@1.28.1/build/global/luxon.min.js',
'es6-object-assign': 'npm:es6-object-assign@1.1.0',
'devextreme': 'npm:devextreme@23.2.5/cjs',
'devextreme-react': 'npm:devextreme-react@23.2.5/cjs',
'jszip': 'npm:jszip@3.10.1/dist/jszip.min.js',
'devextreme-quill': 'npm:devextreme-quill@1.6.4/dist/dx-quill.min.js',
'devexpress-diagram': 'npm:devexpress-diagram@2.2.5/dist/dx-diagram.js',
'devexpress-gantt': 'npm:devexpress-gantt@4.1.51/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@7.4.11/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@2.8.4/standalone.js',
'prettier/parser-html': 'npm:prettier@2.8.4/parser-html.js',
},
packages: {
'devextreme': {
defaultExtension: 'js',
},
'devextreme-react': {
main: 'index.js',
},
'devextreme/events/utils': {
main: 'index',
},
'devextreme/localization/messages': {
format: 'json',
defaultExtension: '',
},
'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>
<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=1.0" />
<link rel="stylesheet" type="text/css" href="https://cdn3.devexpress.com/jslib/23.2.5/css/dx.light.css" />
<link rel="stylesheet" type="text/css" href="styles.css" />
<script src="https://unpkg.com/core-js@2.6.12/client/shim.min.js"></script>
<script src="https://unpkg.com/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>
#chart {
height: 440px;
}