Dynamic data update in React Chart component

19 Sep 202424 minutes to read

Adding a new data point

The addPoint method is used to dynamically add a new data point to the chart series. This method is particularly useful when you want to update the chart with a new data point without having to refresh the entire chart. This method takes two parameters:

  • The first parameter is the new data point to add to your existing data source.
  • The optional second parameter specifies the animation duration for adding the new data point.
import * as React from "react";
import * as ReactDOM from "react-dom";
import {
  ChartComponent, SeriesCollectionDirective, SeriesDirective, Inject,
  Legend, Category, DataLabel, SplineSeries
} from '@syncfusion/ej2-react-charts';
import { data } from './datasource';

function App() {
  const primaryXAxis = { valueType: 'Category', enableTrim: false, majorTickLines: { width: 0 }, majorGridLines: { width: 0 } };
  const primaryYAxis = { minimum: 0, maximum: 800, labelFormat: '{value}M', edgeLabelPlacement: 'Shift' };
  const marker = {
    visible: true,
    dataLabel: {
      visible: true,
      position: 'Top',
      font: {
        fontWeight: '600'
      }
    }
  };
  const legendSettings = { visible: false };
  let chartInstance;
  function clickHandler() {
    chartInstance.series[0].addPoint({ x: 'Japan', y: 118.2 });
  }
  return (<div>
    <button value='add' onClick={clickHandler.bind(this)}>Add Point</button>
    <ChartComponent id='charts' ref={chart => chartInstance = chart} primaryXAxis={primaryXAxis} primaryYAxis={primaryYAxis} legendSettings={legendSettings} title='Internet Users - 2016' chartArea={{ border: { width: 1 } }}>
      <Inject services={[SplineSeries, Legend, DataLabel, Category]} />
      <SeriesCollectionDirective>
        <SeriesDirective dataSource={data} xName='x' yName='y' width={2} name='Users' type='Spline' marker={marker}>
        </SeriesDirective>
      </SeriesCollectionDirective>
    </ChartComponent></div>);
}
;
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,
  Legend, Category, DataLabel, SplineSeries, MarkerSettingsModel, LegendSettingsModel
} from '@syncfusion/ej2-react-charts';
import { data } from './datasource';

function App() {
  const primaryXAxis: AxisModel = { valueType: 'Category', enableTrim: false, majorTickLines: { width: 0 }, majorGridLines: { width: 0 } };
  const primaryYAxis: AxisModel = { minimum: 0, maximum: 800, labelFormat: '{value}M', edgeLabelPlacement: 'Shift' };
  const marker: MarkerSettingsModel = {
    visible: true,
    dataLabel: {
      visible: true,
      position: 'Top',
      font: {
        fontWeight: '600'
      }
    }
  };
  const legendSettings: LegendSettingsModel = { visible: false };
  let chartInstance: ChartComponent;
  function clickHandler() {
    chartInstance.series[0].addPoint({ x: 'Japan', y: 118.2 });
  }

  return (<div>
    <button value='add' onClick={clickHandler.bind(this)}>Add Point</button>
    <ChartComponent id='charts' ref={chart => chartInstance = chart} primaryXAxis={primaryXAxis} primaryYAxis={primaryYAxis} legendSettings={legendSettings} title='Internet Users - 2016' chartArea={{ border: { width: 1 } }}>
      <Inject services={[SplineSeries, Legend, DataLabel, Category]} />
      <SeriesCollectionDirective>
        <SeriesDirective dataSource={data} xName='x' yName='y' width={2} name='Users' type='Spline' marker={marker}>
        </SeriesDirective>
      </SeriesCollectionDirective>
    </ChartComponent></div>)
};
export default App;
ReactDOM.render(<App />, document.getElementById("charts"));
export let data = [
    { x: "Germany",       y: 72 },
    { x: "Russia",        y: 103.1 },
    { x: "Brazil",        y: 139.1 },
    { x: "India",         y: 462.1 },
    { x: "China",         y: 721.4 },
    { x: "USA",           y: 286.9 },
    { x: "Great Britain", y: 115.1 },
    { x: "Nigeria",       y: 97.2 }
];
export let data: Object[] = [
    { x: "Germany",       y: 72 },
    { x: "Russia",        y: 103.1 },
    { x: "Brazil",        y: 139.1 },
    { x: "India",         y: 462.1 },
    { x: "China",         y: 721.4 },
    { x: "USA",           y: 286.9 },
    { x: "Great Britain", y: 115.1 },
    { x: "Nigeria",       y: 97.2 }
];

Removing an existing data point

The removePoint method is used to dynamically remove a data point from the chart series. This method is particularly useful when you want to update the chart by removing an existing data point without having to refresh the entire chart. This method takes two parameters:

  • The first parameter is the index of the data point that needs to be removed from the existing data source.
  • The optional second parameter specifies the animation duration for removing the data point.
import * as React from "react";
import * as ReactDOM from "react-dom";
import {
  ChartComponent, SeriesCollectionDirective, SeriesDirective, Inject,
  Legend, Category, DataLabel, SplineSeries
} from '@syncfusion/ej2-react-charts';
import { data } from './datasource';

function App() {
  const primaryXAxis = { valueType: 'Category', enableTrim: false, majorTickLines: { width: 0 }, majorGridLines: { width: 0 } };
  const primaryYAxis = { minimum: 0, maximum: 800, labelFormat: '{value}M', edgeLabelPlacement: 'Shift' };
  const marker = {
    visible: true,
    dataLabel: {
      visible: true,
      position: 'Top',
      font: {
        fontWeight: '600'
      }
    }
  };
  const legendSettings = { visible: false };
  let chartInstance;
  function clickHandler() {
    chartInstance.series[0].removePoint(0);
  }
  return (<div>
    <button value='remove' onClick={clickHandler.bind(this)}>Remove Point</button>
    <ChartComponent id='charts' ref={chart => chartInstance = chart} primaryXAxis={primaryXAxis} primaryYAxis={primaryYAxis} legendSettings={legendSettings} title='Internet Users - 2016' chartArea={{ border: { width: 1 } }}>
      <Inject services={[SplineSeries, Legend, DataLabel, Category]} />
      <SeriesCollectionDirective>
        <SeriesDirective dataSource={data} xName='x' yName='y' width={2} name='Users' type='Spline' marker={marker}>
        </SeriesDirective>
      </SeriesCollectionDirective>
    </ChartComponent></div>);
}
;
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,
  Legend, Category, DataLabel, SplineSeries, MarkerSettingsModel, LegendSettingsModel
} from '@syncfusion/ej2-react-charts';
import { data } from './datasource';

function App() {
  const primaryXAxis: AxisModel = { valueType: 'Category', enableTrim: false, majorTickLines: { width: 0 }, majorGridLines: { width: 0 } };
  const primaryYAxis: AxisModel = { minimum: 0, maximum: 800, labelFormat: '{value}M', edgeLabelPlacement: 'Shift' };
  const marker: MarkerSettingsModel = {
    visible: true,
    dataLabel: {
      visible: true,
      position: 'Top',
      font: {
        fontWeight: '600'
      }
    }
  };
  const legendSettings: LegendSettingsModel = { visible: false };
  let chartInstance: ChartComponent;
  function clickHandler() {
    chartInstance.series[0].removePoint(0);
  }

  return (<div>
    <button value='remove' onClick={clickHandler.bind(this)}>Remove Point</button>
    <ChartComponent id='charts' ref={chart => chartInstance = chart} primaryXAxis={primaryXAxis} primaryYAxis={primaryYAxis} legendSettings={legendSettings} title='Internet Users - 2016' chartArea={{ border: { width: 1 } }}>
      <Inject services={[SplineSeries, Legend, DataLabel, Category]} />
      <SeriesCollectionDirective>
        <SeriesDirective dataSource={data} xName='x' yName='y' width={2} name='Users' type='Spline' marker={marker}>
        </SeriesDirective>
      </SeriesCollectionDirective>
    </ChartComponent></div>)
};
export default App;
ReactDOM.render(<App />, document.getElementById("charts"));
export let data = [
    { x: "Germany",       y: 72 },
    { x: "Russia",        y: 103.1 },
    { x: "Brazil",        y: 139.1 },
    { x: "India",         y: 462.1 },
    { x: "China",         y: 721.4 },
    { x: "USA",           y: 286.9 },
    { x: "Great Britain", y: 115.1 },
    { x: "Nigeria",       y: 97.2 }
];
export let data: Object[] = [
    { x: "Germany",       y: 72 },
    { x: "Russia",        y: 103.1 },
    { x: "Brazil",        y: 139.1 },
    { x: "India",         y: 462.1 },
    { x: "China",         y: 721.4 },
    { x: "USA",           y: 286.9 },
    { x: "Great Britain", y: 115.1 },
    { x: "Nigeria",       y: 97.2 }
];

Replacing entire data points

To replace the existing data source in the chart with a new data source, you can simply use the setData method. This method allows you to replace the existing data points in the chart series with a new set of data points, enabling you to easily update the chart with new information. This method takes two parameters:

  • The first parameter is the new set of data points to be updated.
  • The optional second parameter specifies the animation duration for updating the new data source.
import * as React from "react";
import * as ReactDOM from "react-dom";
import { ChartComponent, SeriesCollectionDirective, SeriesDirective, Inject, ColumnSeries, Category } from '@syncfusion/ej2-react-charts';
import { data } from './datasource';

function App() {
  const primaryXAxis = { valueType: 'Category', majorGridLines: { width: 0 }, labelStyle: { size: '12px' }, labelIntersectAction: 'Rotate90' };
  const primaryYAxis = { title: 'Sales (in percentage)', labelFormat: '{value}%', lineStyle: { width: 0 }, majorTickLines: { width: 0 }, interval: 5, minimum: 0, maximum: 100 };
  let chartInstance;
  function clickHandler() {
    const newData = data.map((item) => {
      const value = getRandomInt(10, 90);
      return { x: item.x, y: value };
    });
    if (chartInstance.series.length > 0) {
      chartInstance.series[0].setData(newData, 500);
    }
  }

  function getRandomInt(min, max) {
    return Math.floor(Math.random() * (max - min + 1)) + min;
  }

  let axisRangeCalculated = (args) => {
    if (args.axis.name === 'primaryYAxis') {
      args.maximum = args.maximum > 100 ? 100 : args.maximum;
      if (args.maximum > 80) {
        args.interval = 20;
      }
      else if (args.maximum > 40) {
        args.interval = 10;
      }
    }
  }
  return (<div>
    <button value='update' onClick={clickHandler.bind(this)}>Update Data</button>
    <ChartComponent id='charts' ref={chart => chartInstance = chart} primaryXAxis={primaryXAxis} primaryYAxis={primaryYAxis} title='Sales by product' chartArea={{ border: { width: 0 } }} axisRangeCalculated={axisRangeCalculated.bind(this)}>
      <Inject services={[ColumnSeries, Category]} />
      <SeriesCollectionDirective>
        <SeriesDirective dataSource={data} xName='x' yName='y' cornerRadius={{ topLeft: 15, topRight: 15 }} columnWidth={0.5} type='Column'>
        </SeriesDirective>
      </SeriesCollectionDirective>
    </ChartComponent></div>);
}
;
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,
  ColumnSeries, Category, IAxisRangeCalculatedEventArgs
} from '@syncfusion/ej2-react-charts';
import { data } from './datasource';

function App() {
  const primaryXAxis: AxisModel = { valueType: 'Category', majorGridLines: { width: 0 }, labelStyle: { size: '12px' }, labelIntersectAction: 'Rotate90' };
  const primaryYAxis: AxisModel = { title: 'Sales (in percentage)', labelFormat: '{value}%', lineStyle: { width: 0 }, majorTickLines: { width: 0 }, interval: 5, minimum: 0, maximum: 100 };
  let chartInstance: ChartComponent;
  function clickHandler() {
    const newData = data.map((item: { x: string, y: number }) => {
      const value: number = getRandomInt(10, 90);
      return { x: item.x, y: value };
    });
    if (chartInstance.series.length > 0) {
      chartInstance.series[0].setData(newData, 500);
    }
  }

  function getRandomInt(min: number, max: number) {
    return Math.floor(Math.random() * (max - min + 1)) + min;
  }

  let axisRangeCalculated = (args: IAxisRangeCalculatedEventArgs): void => {
    if (args.axis.name === 'primaryYAxis') {
      args.maximum = args.maximum as number > 100 ? 100 : args.maximum;
      if (args.maximum > 80) {
        args.interval = 20;
      }
      else if (args.maximum > 40) {
        args.interval = 10;
      }
    }
  }

  return (<div>
    <button value='update' onClick={clickHandler.bind(this)}>Update Data</button>
    <ChartComponent id='charts' ref={chart => chartInstance = chart} primaryXAxis={primaryXAxis} primaryYAxis={primaryYAxis} title='Sales by product' chartArea={{ border: { width: 0 } }} axisRangeCalculated={axisRangeCalculated.bind(this)}>
      <Inject services={[ColumnSeries, Category]} />
      <SeriesCollectionDirective>
        <SeriesDirective dataSource={data} xName='x' yName='y' cornerRadius={{ topLeft: 15, topRight: 15 }} columnWidth={0.5} type='Column'>
        </SeriesDirective>
      </SeriesCollectionDirective>
    </ChartComponent></div>)
};
export default App;
ReactDOM.render(<App />, document.getElementById("charts"));
export let data = [
    { x: 'Jewellery', y: 75 },
    { x: 'Shoes', y: 45 },
    { x: 'Footwear', y: 73 },
    { x: 'Pet Services', y: 53 },
    { x: 'Business Clothing', y: 85 },
    { x: 'Office Supplies', y: 68 },
    { x: 'Food', y: 45 }
];
export let data: any[] = [
    { x: 'Jewellery', y: 75 },
    { x: 'Shoes', y: 45 },
    { x: 'Footwear', y: 73 },
    { x: 'Pet Services', y: 53 },
    { x: 'Business Clothing', y: 85 },
    { x: 'Office Supplies', y: 68 },
    { x: 'Food', y: 45 }
];

Click to add or remove a data point

You can use mouse or touch events to dynamically add or remove data points from an existing data source by clicking on the appropriate position within the chart area. To add a new data point to the existing data source, click anywhere in the chart area, retrieve the x-axis and y-axis information of the clicked location from the chartMouseClick event arguments. Then, utilize the addPoint method to add a new data point to the existing data source.

To remove a data point from the existing data source, simply click on the desired data point. To achieve this, first, verify whether the clicked data point obtained from chartMouseClick already exists in the data source. If it does, remove it by utilizing the removePoint method based on its index.

import * as React from "react";
import * as ReactDOM from "react-dom";
import { ChartComponent, SeriesCollectionDirective, SeriesDirective, Inject, LineSeries, DataLabel, Tooltip } from '@syncfusion/ej2-react-charts';
import { data } from './datasource';

function App() {
  const primaryXAxis = { edgeLabelPlacement: 'Shift', rangePadding: 'Additional', majorGridLines: { width: 0 } };
  const primaryYAxis = { title: 'Value', interval: 20, lineStyle: { width: 0 }, majorTickLines: { width: 0 } };
  const marker = {
    visible: true,
    isFilled: true,
    border: {
      width: 2,
      color: 'White'
    },
    width: 13,
    height: 13
  };
  const tooltip = { enable: true };
  let chartInstance;
  const axisRangeCalculated = (args) => {
    if (args.axis.name === 'primaryXAxis') {
      if (args.interval < 10) {
        args.maximum = args.maximum + 10;
        args.minimum = args.minimum - 10;
        args.interval = 10;
      }
    }
    if (args.axis.name === 'primaryYAxis') {
      if (args.maximum <= 60) {
        args.interval = 10;
      }
    }
  }

  const chartMouseClick = (args) => {
    let isRemoved = false;
    if (args.axisData) {
      for (let i = 0; i < (chartInstance.series[0]).points.length; i++) {
        const markerWidth = (chartInstance.series[0]).marker.width / 2;
        let roundedX = Math.round(args.axisData['primaryXAxis']) + markerWidth;
        let roundedY = Math.round(args.axisData['primaryYAxis']) + markerWidth;
        let pointX = Math.round((chartInstance.series[0]).points[i].x) + markerWidth;
        let pointY = Math.round((chartInstance.series[0]).points[i].y) + markerWidth;
        if ((roundedX === pointX || roundedX + 1 === pointX || roundedX - 1 === pointX) &&
          (roundedY === pointY || roundedY + 1 === pointY || roundedY - 1 === pointY)) {
          if ((chartInstance.series[0]).points.length > 1) {
            const points = (chartInstance.series[0]).points;
            const duration = i === 0 || i === points[points.length - 1].index ? 500 : 0;
            chartInstance.series[0].removePoint(i, duration);
          }
          isRemoved = true;
        }
      }
      if (!isRemoved) {
        chartInstance.series[0].addPoint({ x: Math.round(args.axisData['primaryXAxis']), y: Math.round(args.axisData['primaryYAxis']) });
      }
    }
  };
  return (<div>
    <ChartComponent id='charts' ref={chart => chartInstance = chart} primaryXAxis={primaryXAxis} primaryYAxis={primaryYAxis} tooltip={tooltip} title='User supplied data' chartArea={{ border: { width: 0 } }} axisRangeCalculated={axisRangeCalculated.bind(this)} chartMouseClick={chartMouseClick.bind(this)}>
      <Inject services={[LineSeries, DataLabel, Tooltip]} />
      <SeriesCollectionDirective>
        <SeriesDirective dataSource={data} xName='x' yName='y' marker={marker} width={3} type='Line'>
        </SeriesDirective>
      </SeriesCollectionDirective>
    </ChartComponent></div>);
}
;
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,
  LineSeries, DataLabel, Tooltip, MarkerSettingsModel, IAxisRangeCalculatedEventArgs, Series, TooltipSettingsModel, IMouseEventArgs
} from '@syncfusion/ej2-react-charts';
import { data } from './datasource';

function App() {
  const primaryXAxis: AxisModel = { edgeLabelPlacement: 'Shift', rangePadding: 'Additional', majorGridLines: { width: 0 } };
  const primaryYAxis: AxisModel = { title: 'Value', interval: 20, lineStyle: { width: 0 }, majorTickLines: { width: 0 } };
  const marker: MarkerSettingsModel = {
    visible: true,
    isFilled: true,
    border: {
      width: 2,
      color: 'White'
    },
    width: 13,
    height: 13
  };
  const tooltip: TooltipSettingsModel = { enable: true };
  let chartInstance: ChartComponent;
  const axisRangeCalculated = (args: IAxisRangeCalculatedEventArgs): void => {
    if (args.axis.name === 'primaryXAxis') {
      if (args.interval < 10) {
        args.maximum = args.maximum + 10;
        args.minimum = args.minimum - 10;
        args.interval = 10;
      }
    }
    if (args.axis.name === 'primaryYAxis') {
      if (args.maximum <= 60) {
        args.interval = 10;
      }
    }
  }

  const chartMouseClick = (args: IMouseEventArgs): void => {
    let isRemoved: boolean = false;
    if (args.axisData) {
      for (let i: number = 0; i < (chartInstance.series[0] as Series).points.length; i++) {
        const markerWidth: number = (chartInstance.series[0] as Series).marker.width / 2;
        let roundedX: number = Math.round(args.axisData['primaryXAxis']) + markerWidth;
        let roundedY: number = Math.round(args.axisData['primaryYAxis']) + markerWidth;
        let pointX: number = Math.round((chartInstance.series[0] as Series).points[i].x as number) + markerWidth;
        let pointY: number = Math.round((chartInstance.series[0] as Series).points[i].y as number) + markerWidth;
        if ((roundedX === pointX || roundedX + 1 === pointX || roundedX - 1 === pointX) &&
          (roundedY === pointY || roundedY + 1 === pointY || roundedY - 1 === pointY)) {
          if ((chartInstance.series[0] as Series).points.length > 1) {
            const points = (chartInstance.series[0] as Series).points;
            const duration: number = i === 0 || i === points[points.length - 1].index ? 500 : 0;
            chartInstance.series[0].removePoint(i, duration);
          }
          isRemoved = true;
        }
      }
      if (!isRemoved) {
        chartInstance.series[0].addPoint({ x: Math.round(args.axisData['primaryXAxis']), y: Math.round(args.axisData['primaryYAxis']) });
      }
    }
  };

  return (<div>
    <ChartComponent id='charts' ref={chart => chartInstance = chart} primaryXAxis={primaryXAxis} primaryYAxis={primaryYAxis} tooltip={tooltip} title='User supplied data' chartArea={{ border: { width: 0 } }} axisRangeCalculated={axisRangeCalculated.bind(this)} chartMouseClick={chartMouseClick.bind(this)}>
      <Inject services={[LineSeries, DataLabel, Tooltip]} />
      <SeriesCollectionDirective>
        <SeriesDirective dataSource={data} xName='x' yName='y' marker={marker} width={3} type='Line'>
        </SeriesDirective>
      </SeriesCollectionDirective>
    </ChartComponent></div>)
};
export default App;
ReactDOM.render(<App />, document.getElementById("charts"));
export let data = [
    { x: 20, y: 20 },
    { x: 80, y: 80 }
];
export let data: Object[] = [
    { x: 20, y: 20 },
    { x: 80, y: 80 }
];