Percentage tooltip in Angular Chart component

13 Mar 20264 minutes to read

By using the tooltipRender event, you can show the percentage value for each point of pie series in tooltip.

To show the percentage value in pie tooltip, follow the given step:

Step 1:

By using the tooltipRender event, you can access the args.point.y and args.series.sumOfPoints values from the event arguments. You can use these values to calculate the percentage value for each point of pie series. To display the percentage value in tooltip, use the args.content property.

app.component.ts

import { ChartModule, ChartAllModule, AccumulationChartAllModule } from '@syncfusion/ej2-angular-charts'
import { AccumulationChartModule } from '@syncfusion/ej2-angular-charts'
import { PieSeriesService, AccumulationTooltipService, AccumulationDataLabelService } from '@syncfusion/ej2-angular-charts'
import {
    LineSeriesService, DateTimeService, DataLabelService, StackingColumnSeriesService, CategoryService,
    StepAreaSeriesService, SplineSeriesService, ScrollBarService, ChartAnnotationService, LegendService, TooltipService, StripLineService,
    SelectionService, ScatterSeriesService, ZoomService, ColumnSeriesService, AreaSeriesService, RangeAreaSeriesService
} from '@syncfusion/ej2-angular-charts'


import { Component, OnInit } from '@angular/core';
import { IAccTooltipRenderEventArgs } from '@syncfusion/ej2-angular-charts';
@Component({
imports: [
         ChartModule, ChartAllModule, AccumulationChartAllModule, AccumulationChartModule
    ],

providers: [LineSeriesService, DateTimeService, ColumnSeriesService, DataLabelService, ZoomService, StackingColumnSeriesService, CategoryService,
        StepAreaSeriesService, SplineSeriesService, ChartAnnotationService, LegendService, TooltipService, StripLineService,
        PieSeriesService, AccumulationTooltipService, ScrollBarService, AccumulationDataLabelService, SelectionService, ScatterSeriesService,
        AreaSeriesService, RangeAreaSeriesService ],
standalone: true,
    selector: 'app-container',
    template: `<ejs-accumulationchart id="chart-container" [tooltip]='tooltip' [title]='title' (tooltipRender)='tooltipRender($event)'>
        <e-accumulation-series-collection>
            <e-accumulation-series [dataSource]='piedata' xName='x' yName='y' [dataLabel]='datalabel' radius="70%"></e-accumulation-series>
        </e-accumulation-series-collection>
    </ejs-accumulationchart>`
})
export class AppComponent implements OnInit {
    public piedata?: Object[];
    public datalabel?: Object;
    public tooltip?: Object;
    public title?: String;
    public tooltipRender(args: IAccTooltipRenderEventArgs): void {
           let value  = args.point.y / args.series.sumOfPoints * 100;
           args["text"] = args.point.x + ' : ' + Math.ceil(value) + '' + '%';
        };
    ngOnInit(): void {
        this.datalabel = { visible: true };
        this.tooltip = {enable: true};
        this.title = 'Mobile Browser Statistics';
        this.piedata = [
                    { 'x': 'Chrome', y: 37 }, { 'x': 'UC Browser', y: 17 },
                    { 'x': 'iPhone', y: 19 }, { 'x': 'Others', y: 4 }, { 'x': 'Opera', y: 11 }
                ];
    }

}

main.ts

import { bootstrapApplication } from '@angular/platform-browser';
import { AppComponent } from './app.component';
import 'zone.js';
bootstrapApplication(AppComponent).catch((err) => console.error(err));