Data markers in Angular Chart component

3 Feb 202616 minutes to read

Data markers are visual indicators placed at each data point on a series, helping to clearly identify and highlight individual values in your chart. Markers improve readability and accessibility, especially in line and area charts where data points may otherwise be unclear. Customize marker shape, color, size, and appearance to match your design requirements.

Marker

Enable markers for data points by setting the visible option to true in the marker property. Each series receives distinct markers by default, improving visual differentiation.

import { NgModule } from '@angular/core'
import { BrowserModule } from '@angular/platform-browser'
import { ChartModule } from '@syncfusion/ej2-angular-charts'
import { CategoryService, LineSeriesService } from '@syncfusion/ej2-angular-charts'



import { Component, OnInit } from '@angular/core';
import { markerData } from './datasource';

@Component({
imports: [
         ChartModule
    ],

providers: [ CategoryService, LineSeriesService],
standalone: true,
    selector: 'app-container',
    template: `<ejs-chart id="chart-container" [primaryXAxis]='primaryXAxis'[primaryYAxis]='primaryYAxis' [title]='title'>
        <e-series-collection>
            <e-series [dataSource]='chartData' type='Line' xName='x' yName='y' name='December 2007' width=2 [marker]='marker'></e-series>
            <e-series [dataSource]='chartData' type='Line' xName='x' yName='y1' name='December 2008' width=2 [marker]='marker'></e-series>
        </e-series-collection>
    </ejs-chart>`
})
export class AppComponent implements OnInit {
    public primaryXAxis?: Object;
    public chartData?: Object[];
    public title?: string;
    public marker?: Object;
    primaryYAxis: any;
    ngOnInit(): void {
        this.chartData = markerData;
        this.primaryXAxis = {
            valueType: 'Category', interval: 1,
        };
        this.marker = { visible: true };
        this.title = 'FB Penetration of Internet Audience';
    }

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

Shape

Assign different shapes to markers such as Rectangle, Circle, Diamond, Triangle, and others using the shape property. Shape selection helps distinguish between multiple series and improves visual clarity.

import { NgModule } from '@angular/core'
import { BrowserModule } from '@angular/platform-browser'
import { ChartModule } from '@syncfusion/ej2-angular-charts'
import { CategoryService, LineSeriesService } from '@syncfusion/ej2-angular-charts'



import { Component, OnInit } from '@angular/core';
import { markerData } from './datasource';

@Component({
imports: [
         ChartModule
    ],

providers: [ CategoryService, LineSeriesService],
standalone: true,
    selector: 'app-container',
    template: `<ejs-chart id="chart-container" [primaryXAxis]='primaryXAxis'[primaryYAxis]='primaryYAxis' [title]='title'>
        <e-series-collection>
            <e-series [dataSource]='chartData' type='Line' xName='x' yName='y' name='December 2007' width=2 [marker]='marker'></e-series>
        </e-series-collection>
    </ejs-chart>`
})
export class AppComponent implements OnInit {
    public primaryXAxis?: Object;
    public chartData?: Object[];
    public title?: string;
    public marker?: Object;
    primaryYAxis: any;
    ngOnInit(): void {
        this.chartData = markerData;
        this.primaryXAxis = {
            valueType: 'Category'
        };
        this.marker = { visible: true, width: 10, height: 10, shape: 'Diamond' };
        this.title = 'FB Penetration of Internet Audience';
    }

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

Note : To know more about the marker shape type refer the shape.

Images

Use custom images as markers instead of predefined shapes by setting the imageUrl property. This allows branded or thematic markers that enhance visual appeal and user engagement.

import { NgModule } from '@angular/core'
import { BrowserModule } from '@angular/platform-browser'
import { ChartModule } from '@syncfusion/ej2-angular-charts'
import { CategoryService, LineSeriesService } from '@syncfusion/ej2-angular-charts'




import { Component, OnInit } from '@angular/core';
import { imageData } from './datasource';

@Component({
imports: [
         ChartModule
    ],

providers: [ CategoryService, LineSeriesService],
standalone: true,
    selector: 'app-container',
    template: `<ejs-chart id="chart-container" [primaryXAxis]='primaryXAxis'[primaryYAxis]='primaryYAxis' [title]='title'>
        <e-series-collection>
            <e-series [dataSource]='chartData' type='Line' xName='x' yName='y' name='India' width=2 [marker]='marker'></e-series>
        </e-series-collection>
    </ejs-chart>`
})
export class AppComponent implements OnInit {
    public primaryXAxis?: Object;
    public chartData?: Object[];
    public title?: string;
    public marker?: Object;
    primaryYAxis: any;
    ngOnInit(): void {
        this.chartData = imageData;
        this.primaryXAxis = {
            valueType: 'Category'
        };
        this.marker = { visible: true,
                        width: 10, height: 10, shape: 'Image',
                        imageUrl:'./sun_annotation.png'
        };
        this.title = 'Temperature flow over months';
    }

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

Customization

Customize marker appearance by modifying the fill (background color) and border properties. Combined with shape and image options, these customizations enable comprehensive marker styling to match your application design.

import { NgModule } from '@angular/core'
import { BrowserModule } from '@angular/platform-browser'
import { ChartModule } from '@syncfusion/ej2-angular-charts'
import { CategoryService, LineSeriesService } from '@syncfusion/ej2-angular-charts'



import { Component, OnInit } from '@angular/core';
import { markerData } from './datasource';

@Component({
imports: [
         ChartModule
    ],

providers: [ CategoryService, LineSeriesService],
standalone: true,
    selector: 'app-container',
    template: `<ejs-chart id="chart-container" [primaryXAxis]='primaryXAxis'[primaryYAxis]='primaryYAxis' [title]='title'>
        <e-series-collection>
            <e-series [dataSource]='chartData' type='Line' xName='x' yName='y' name='December 2007' width=2 [marker]='marker'></e-series>
        </e-series-collection>
    </ejs-chart>`
})
export class AppComponent implements OnInit {
    public primaryXAxis?: Object;
    public chartData?: Object[];
    public title?: string;
    public marker?: Object;
    primaryYAxis: any;
    ngOnInit(): void {
        this.chartData = markerData;
        this.primaryXAxis = {
            valueType: 'Category'
        };
        this.marker = { visible: true,  fill: 'Red', height: 10, width: 10,
                    border:{width: 2, color: 'blue'} };
        this.title = 'FB Penetration of Internet Audience';
    }

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

Customizing specific point

Use the pointRender event to customize markers for individual data points. This event allows you to conditionally change shape, color, and border properties based on data values or other criteria.

import { NgModule } from '@angular/core'
import { BrowserModule } from '@angular/platform-browser'
import { ChartModule } from '@syncfusion/ej2-angular-charts'
import { CategoryService, LineSeriesService } from '@syncfusion/ej2-angular-charts'



import { Component, OnInit } from '@angular/core';
import { markerData } from './datasource';
import { IPointRenderEventArgs } from '@syncfusion/ej2-angular-charts';

@Component({
imports: [
         ChartModule
    ],

providers: [ CategoryService, LineSeriesService],
standalone: true,
    selector: 'app-container',
    template: `<ejs-chart id="chart-container" [primaryXAxis]='primaryXAxis'[primaryYAxis]='primaryYAxis' (pointRender)='pointRender($event)' [title]='title'>
        <e-series-collection>
            <e-series [dataSource]='chartData' type='Line' xName='x' yName='y' name='December 2007' width=2 [marker]='marker'></e-series>
        </e-series-collection>
    </ejs-chart>`
})
export class AppComponent implements OnInit {
    public primaryXAxis?: Object;
    public chartData?: Object[];
    public title?: string;
    public marker?: Object;
    primaryYAxis: any;
    public pointRender(args: IPointRenderEventArgs): void {
        if(args.point.index === 3) {
                args.fill = 'red'
        }
    };
    ngOnInit(): void {
        this.chartData = markerData;
        this.primaryXAxis = {
            valueType: 'Category'
        };
        this.marker = {  visible: true,
                    height: 10, width: 10 };
        this.title = 'FB Penetration of Internet Audience';
    }

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

Fill marker with series color

Fill markers with the series color by enabling the isFilled property. This creates a cohesive visual design where markers inherit the series color automatically.

import { NgModule } from '@angular/core'
import { BrowserModule } from '@angular/platform-browser'
import { ChartModule } from '@syncfusion/ej2-angular-charts'
import { CategoryService, LineSeriesService } from '@syncfusion/ej2-angular-charts'



import { Component, OnInit } from '@angular/core';
import { markerData } from './datasource';

@Component({
imports: [
         ChartModule
    ],

providers: [ CategoryService, LineSeriesService],
standalone: true,
    selector: 'app-container',
    template: `<ejs-chart id="chart-container" [primaryXAxis]='primaryXAxis'[primaryYAxis]='primaryYAxis' (pointRender)='pointRender($event)' [title]='title'>
        <e-series-collection>
            <e-series [dataSource]='chartData' type='Line' xName='x' yName='y' name='December 2007' width=2 [marker]='marker'></e-series>
        </e-series-collection>
    </ejs-chart>`
})
export class AppComponent implements OnInit {
    pointRender($event: any) {
    }
    public primaryXAxis?: Object;
    public chartData?: Object[];
    public title?: string;
    public marker?: Object;
    primaryYAxis: any;
    ngOnInit(): void {
        this.chartData = markerData;
        this.primaryXAxis = {
            valueType: 'Category'
        };
        this.marker = {  visible: true,
            height: 10, width: 10, isFilled: true };
        this.title = 'FB Penetration of Internet Audience';
    }

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

See also