Package Exports

recharts-to-png
recharts-to-png/dist/index.esm.js
recharts-to-png/dist/index.js

This package does not declare an exports field, so the exports above have been automatically detected and optimized by JSPM instead. If any package subpath is missing, it is recommended to post an issue to the original package (recharts-to-png) to support the "exports" field. If that is not possible, create a JSPM override to customize the exports field for this package.

Readme

recharts-to-png

Uses html2canvas to convert a Recharts chart to PNG.

Inspired by these Stack Overflow questions and answers from peter.bartos and AlbertMunichMar. Special thanks to HarmNullix for helping to improve the performance of this library.

Install

npm install recharts-to-png

Demo

See the demo here. It implements useCurrentPng with different chart types and file-saver.

Source:

For usage with class components, see an implementation of the CurrentPng component with render props here.

Usage

useCurrentPng

useCurrentPng is a React hook that returns a tuple. The first parameter is a promise that will return a string if the PNG is valid. The second parameter is an object with two properties: ref, which is required to be attached to the target Recharts component, and isLoading, which is optional and changes state from false to true while the PNG is being generated and downloaded.

function MyApp(props) {
  // useCurrentPng usage (isLoading is optional)
  const [getPng, { ref, isLoading }] = useCurrentPng();

  // Can also pass in options for html2canvas
  // const [getPng, { ref }] = useCurrentPng({ backgroundColor: '#000' });

  const handleDownload = useCallback(async () => {
    const png = await getPng();

    // Verify that png is not undefined
    if (png) {
      // Download with FileSaver
      FileSaver.saveAs(png, 'myChart.png');
    }
  }, [getPng]);

  return (
    <>
      <ComposedChart data={props.data} ref={ref}>
        <XAxis dataKey="name" />
        <YAxis />
        <Tooltip />
        <Legend />
        <CartesianGrid stroke="#f5f5f5" />
        <Area type="monotone" dataKey="amt" fill="#8884d8" stroke="#8884d8" />
        <Bar dataKey="pv" barSize={20} fill="#413ea0" />
        <Line type="monotone" dataKey="uv" stroke="#ff7300" />
        <Brush dataKey="name" height={30} stroke="#8884d8" />
      </ComposedChart>
      <br/>
      <button onClick={handleDownload}>
        {isLoading ? 'Downloading...' : 'Download Chart'}
      </button>
    </>
  );

CurrentPng

Per user request, CurrentPng implements the same functionality as useCurrentPng but as a class component using render props. See background in this issue.

// index.tsx
ReactDOM.render(
  <CurrentPng>{(props) => <RenderPropsExample {...props} />}</CurrentPng>,
  rootElement
);

// RenderPropsExample.tsx
export default class RenderPropsExample extends React.Component<CurrentPngProps, State> {
  state: State = {
    chartData: [],
  };

  componentDidMount() {
    this.setState({
      chartData: getData(100),
    });
  }

  handleDownload = async () => {
    const png = await this.props.getPng();

    if (png) {
      FileSaver.saveAs(png, 'chart.png');
    }
  };

  render() {
    return (
      <>
        <h4>
          <code>Example: Download chart with React.Component Render Props </code>
        </h4>
        <ResponsiveContainer width="100%" height={300}>
          <ComposedChart data={this.state.chartData} ref={this.props.chartRef}>
            <XAxis dataKey="name" />
            <YAxis />
            <Tooltip />
            <Legend />
            <CartesianGrid stroke="#f5f5f5" />
            <Area type="monotone" dataKey="amt" fill="#8884d8" stroke="#8884d8" />
            <Bar dataKey="pv" barSize={20} fill="#413ea0" />
            <Line type="monotone" dataKey="uv" stroke="#ff7300" />
            <Brush dataKey="name" height={30} stroke="#8884d8" />
          </ComposedChart>
        </ResponsiveContainer>
        <br />
        <button disabled={this.props.isLoading} onClick={() => this.handleDownload()}>
          {this.props.isLoading ? (
            <span className="download-button-content">
              <i className="gg-spinner" />
              <span className="download-button-text">
                <code>Downloading...</code>
              </span>
            </span>
          ) : (
            <span className="download-button-content">
              <i className="gg-software-download" />
              <span className="download-button-text">
                <code>Download Chart</code>
              </span>
            </span>
          )}
        </button>
      </>
    );
  }
}

Contributing/Developing

Fork/clone the repository
- How to contribute to a project on Github
Install dependencies
```
npm i
```
Build recharts-to-png in watch mode
```
npm run watch
```
Start the demo to observe your changes
```
npm run demo
```
Ensure all tests pass
```
npm run test
```