Chart annotations in React Chart component

20 Jan 202315 minutes to read

Annotations are used to mark the specific area of interest in the chart area with texts, shapes or images.

You can add annotations to the chart by using the annotations option. By using the content option of annotation object, you can specify the id of the element that needs to be displayed in the chart area.

import * as React from "react";
import * as ReactDOM from "react-dom";
import { ChartComponent, SeriesCollectionDirective, SeriesDirective, Inject, ChartAnnotation, AnnotationsDirective, AnnotationDirective, Legend, Category, Tooltip, DataLabel, ColumnSeries } from '@syncfusion/ej2-react-charts';
import { columnData } from 'datasource.ts';
function App() {
    const primaryxAxis = { valueType: 'Category', title: 'Countries' };
    const primaryyAxis = { minimum: 0, maximum: 80, interval: 20, title: 'Medals' };
    const border = { width: 2, color: 'grey' };
    const animation = { enable: true, duration: 1200, delay: 100 };
    return <ChartComponent id='charts' primaryXAxis={primaryxAxis} primaryYAxis={primaryyAxis} title='Olympic Medals'>
      <Inject services={[ColumnSeries, Legend, Tooltip, DataLabel, Category, ChartAnnotation]}/>
      <AnnotationsDirective>
        <AnnotationDirective content='70 Gold Medals' region='Series' coordinateUnits='Point' x='Japan' y={75}>
        </AnnotationDirective>
      </AnnotationsDirective>
      <SeriesCollectionDirective>
        <SeriesDirective dataSource={columnData} xName='country' yName='gold' name='Gold' border={border} animation={animation} type='Column'>
        </SeriesDirective>
      </SeriesCollectionDirective>
    </ChartComponent>;
}
;
export default App;
ReactDOM.render(<App />, document.getElementById("charts"));
import * as React from "react";
import * as ReactDOM from "react-dom";
import { AxisModel, ChartComponent, SeriesCollectionDirective, SeriesDirective, Inject, ChartAnnotation, AnnotationsDirective, AnnotationDirective, Legend, Category, Tooltip, DataLabel, ColumnSeries}from'@syncfusion/ej2-react-charts';
import { columnData } from 'datasource.ts';

function App() {

  const primaryxAxis: AxisModel = { valueType: 'Category', title: 'Countries' };
  const primaryyAxis: AxisModel = { minimum: 0, maximum: 80, interval: 20, title: 'Medals' };
  const border = { width: 2, color: 'grey' };
  const animation = { enable: true, duration: 1200, delay: 100 };

  return <ChartComponent id='charts'
      primaryXAxis={primaryxAxis}
      primaryYAxis={primaryyAxis}
      title='Olympic Medals'>
      <Inject services={[ColumnSeries, Legend, Tooltip, DataLabel, Category, ChartAnnotation]} />
      <AnnotationsDirective>
        <AnnotationDirective content='70 Gold Medals' region='Series' coordinateUnits='Point' x='Japan' y={75}>
        </AnnotationDirective>
      </AnnotationsDirective>
      <SeriesCollectionDirective>
        <SeriesDirective dataSource={columnData} xName='country' yName='gold' name='Gold'
          border={border}
          animation={animation} type='Column'>
        </SeriesDirective>
      </SeriesCollectionDirective>
    </ChartComponent>

};
export default App;
ReactDOM.render(<App />, document.getElementById("charts"));

Note: To use annotation feature in chart, we need to inject ChartAnnotation module into the services.

Region

Annotations can be placed either with respect to Series or Chart. by default, it will placed with respect to Chart.

import * as React from "react";
import * as ReactDOM from "react-dom";
import { ChartComponent, SeriesCollectionDirective, SeriesDirective, Inject, ChartAnnotation, AnnotationsDirective, AnnotationDirective, Legend, Category, Tooltip, DataLabel, ColumnSeries } from '@syncfusion/ej2-react-charts';
import { columnData } from 'datasource.ts';
function App() {
    const primaryxAxis = { valueType: 'Category', title: 'Countries' };
    const primaryyAxis = { minimum: 0, maximum: 80, interval: 20, title: 'Medals' };
    const border = { width: 2, color: 'grey' };
    const animation = { enable: true, duration: 1200, delay: 100 };
    const template = chartTemplate;
    function chartTemplate() {
        return (<div className='template'>
      <div>Highest Medal Count</div>
    </div>);
    }
    return <ChartComponent id='charts' primaryXAxis={primaryxAxis} primaryYAxis={primaryyAxis} title='Olympic Medals'>
      <Inject services={[ColumnSeries, Legend, Tooltip, DataLabel, Category, ChartAnnotation]}/>
      <AnnotationsDirective>
        <AnnotationDirective content={template} region='Series' coordinateUnits='Point' x='Japan' y={75}>
        </AnnotationDirective>
      </AnnotationsDirective>
      <SeriesCollectionDirective>
        <SeriesDirective dataSource={columnData} xName='country' yName='gold' name='Gold' border={border} animation={animation} type='Column'>
        </SeriesDirective>
      </SeriesCollectionDirective>
    </ChartComponent>;
}
;
export default App;
ReactDOM.render(<App />, document.getElementById("charts"));
import * as React from "react";
import * as ReactDOM from "react-dom";
import { AxisModel, ChartComponent, SeriesCollectionDirective, SeriesDirective, Inject, ChartAnnotation, AnnotationsDirective, AnnotationDirective, Legend, Category, Tooltip, DataLabel, ColumnSeries} from'@syncfusion/ej2-react-charts';
import { columnData } from 'datasource.ts';

function App() {

  const primaryxAxis: AxisModel = { valueType: 'Category', title: 'Countries' };
  const primaryyAxis: AxisModel = { minimum: 0, maximum: 80, interval: 20, title: 'Medals' };
  const border = { width: 2, color: 'grey' };
  const animation = { enable: true, duration: 1200, delay: 100 };
  const template: any = chartTemplate;
  function chartTemplate(): any {
    return (<div className='template'>
      <div>Highest Medal Count</div>
    </div>);
  }

  return <ChartComponent id='charts'
      primaryXAxis={primaryxAxis}
      primaryYAxis={primaryyAxis}
      title='Olympic Medals'>
      <Inject services={[ColumnSeries, Legend, Tooltip, DataLabel, Category, ChartAnnotation]} />
      <AnnotationsDirective>
        <AnnotationDirective content={template} region='Series' coordinateUnits='Point' x='Japan' y={75}>
        </AnnotationDirective>
      </AnnotationsDirective>
      <SeriesCollectionDirective>
        <SeriesDirective dataSource={columnData} xName='country' yName='gold' name='Gold'
          border={border}
          animation={animation} type='Column'>
        </SeriesDirective>
      </SeriesCollectionDirective>
    </ChartComponent>

};
export default App;
ReactDOM.render(<App />, document.getElementById("charts"));

Co-ordinate Units

Specified the coordinates units of the annotation either Pixel or Point.

import * as React from "react";
import * as ReactDOM from "react-dom";
import { ChartComponent, SeriesCollectionDirective, SeriesDirective, Inject, ChartAnnotation, AnnotationsDirective, AnnotationDirective, Legend, Category, Tooltip, DataLabel, ColumnSeries } from '@syncfusion/ej2-react-charts';
import { columnData } from 'datasource.ts';
function App() {
    const primaryxAxis = { valueType: 'Category', title: 'Countries' };
    const primaryyAxis = { minimum: 0, maximum: 80, interval: 20, title: 'Medals' };
    const border = { width: 2, color: 'grey' };
    const animation = { enable: true, duration: 1200, delay: 100 };
    const template = chartTemplate;
    function chartTemplate() {
        return (<div className='charttemplate'>
      <div> Annotation In Pixel </div>
    </div>);
    }
    return <ChartComponent id='charts' primaryXAxis={primaryxAxis} primaryYAxis={primaryyAxis} title='Olympic Medals'>
      <Inject services={[ColumnSeries, Legend, Tooltip, DataLabel, Category, ChartAnnotation]}/>
      <AnnotationsDirective>
        <AnnotationDirective content={template} coordinateUnits='Pixel' x={150} y={50}>
        </AnnotationDirective>
      </AnnotationsDirective>
      <SeriesCollectionDirective>
        <SeriesDirective dataSource={columnData} xName='country' yName='gold' name='Gold' border={border} animation={animation} type='Column'>
        </SeriesDirective>
      </SeriesCollectionDirective>
    </ChartComponent>;
}
;
export default App;
ReactDOM.render(<App />, document.getElementById("charts"));
import * as React from "react";
import * as ReactDOM from "react-dom";
import { AxisModel,ChartComponent, SeriesCollectionDirective, SeriesDirective, Inject, ChartAnnotation, AnnotationsDirective, AnnotationDirective, Legend, Category, Tooltip, DataLabel, ColumnSeries}from'@syncfusion/ej2-react-charts';
import { columnData } from 'datasource.ts';

function App() {

  const primaryxAxis: AxisModel = { valueType: 'Category', title: 'Countries' };
  const primaryyAxis: AxisModel = { minimum: 0, maximum: 80, interval: 20, title: 'Medals' };
  const border = { width: 2, color: 'grey' };
  const animation = { enable: true, duration: 1200, delay: 100 };
  const template: any = chartTemplate;
  function chartTemplate(): any {
    return (<div className='charttemplate'>
      <div> Annotation In Pixel </div>
    </div>);
  }

  return <ChartComponent id='charts'
      primaryXAxis={primaryxAxis}
      primaryYAxis={primaryyAxis}
      title='Olympic Medals'>
      <Inject services={[ColumnSeries, Legend, Tooltip, DataLabel, Category, ChartAnnotation]} />
      <AnnotationsDirective>
        <AnnotationDirective content={template}
          coordinateUnits='Pixel' x={150} y={50}>
        </AnnotationDirective>
      </AnnotationsDirective>
      <SeriesCollectionDirective>
        <SeriesDirective dataSource={columnData} xName='country' yName='gold' name='Gold'
          border={border}
          animation={animation} type='Column'>
        </SeriesDirective>
      </SeriesCollectionDirective>
    </ChartComponent>

};
export default App;
ReactDOM.render(<App />, document.getElementById("charts"));