Tooltip in Angular Heatmap chart component

27 Apr 202416 minutes to read

Tooltip is used to provide the details of the heat map cell, and this can be displayed, while hovering the cursor over the cell or performing tap action in touch devices.

You can enable the tooltip by setting the showTooltip property to true and injecting the Tooltip module using the HeatMap.Inject(Tooltip).

app.component.ts
main.ts
import { NgModule } from '@angular/core'
import { BrowserModule } from '@angular/platform-browser'
import { HeatMapModule} from '@syncfusion/ej2-angular-heatmap'
import { TooltipService} from '@syncfusion/ej2-angular-heatmap'




import { Component, ViewEncapsulation } from '@angular/core';

@Component({
imports: [
         HeatMapModule
    ],

providers: [TooltipService],
standalone: true,
    selector: 'my-app',
    template:
       `<ejs-heatmap id='container' style="display:block;" [dataSource]='dataSource' [xAxis]='xAxis'  [yAxis]='yAxis'
       [titleSettings]='titleSettings' [cellSettings]='cellSettings' [showTooltip]='showTooltip'>
        </ejs-heatmap>`,
    encapsulation: ViewEncapsulation.None
})
export class AppComponent{

dataSource: Object[] = [
   [0.72, 0.71, 0.71, 0.67, 0.72, 0.53, 0.53, 0.56, 0.58, 0.56],
    [2.28, 2.29, 2.09, 1.84, 1.64, 1.49, 1.49, 1.39, 1.32, 1.23],
    [2.02, 2.17, 2.30, 2.39, 2.36, 2.52, 2.62, 2.57, 2.57, 2.74],
    [3.21, 3.26, 3.45, 3.47, 3.42, 3.34, 3.14, 2.83, 2.64, 2.61],
    [3.22, 3.13, 3.04, 2.95, 2.69, 2.49, 2.27, 2.18, 2.06, 1.87],
    [3.30, 3.39, 3.40, 3.48, 3.60, 3.67, 3.73, 3.79, 3.79, 4.07],
    [5.80, 5.74, 5.64, 5.44, 5.18, 5.08, 5.07, 5.00, 5.35, 5.47],
    [6.91, 7.40, 8.13, 8.80, 9.04, 9.24, 9.43, 9.35, 9.49, 9.69]];

   titleSettings: Object = {
            text: 'Crude Oil Production of Non-OPEC Countries (in Million barrels per day)',
            textStyle: {
                size: '15px',
                fontWeight: '500',
                fontStyle: 'Normal',
                fontFamily: 'Segoe UI'
            }
        };
        xAxis: Object = {
            labels: ['Canada', 'China', 'Egypt', 'Mexico', 'Norway', 'Russia', 'UK', 'USA']
        };
        yAxis: Object = {
             labels: ['2000', '2001', '2002', '2003', '2004', '2005', '2006', '2007', '2008', '2009', '2010'],
        };
        public cellSettings: Object = {
            showLabel: false,
        };
        public showTooltip: Boolean = true;
}
import { bootstrapApplication } from '@angular/platform-browser';
import { AppComponent } from './app.component';
import 'zone.js';
bootstrapApplication(AppComponent).catch((err) => console.error(err));

In heat map, you can customize the tooltip using the tooltipRender client-side event.

app.component.ts
main.ts
import { NgModule } from '@angular/core'
import { BrowserModule } from '@angular/platform-browser'
import { HeatMapModule} from '@syncfusion/ej2-angular-heatmap'
import { TooltipService} from '@syncfusion/ej2-angular-heatmap'




import { Component, ViewEncapsulation } from '@angular/core';
import { ITooltipEventArgs } from '@syncfusion/ej2-angular-heatmap';

@Component({
imports: [
         HeatMapModule
    ],

providers: [TooltipService],
standalone: true,
    selector: 'my-app',
    template:
       `<ejs-heatmap id='container' style="display:block;" [dataSource]='dataSource' [xAxis]='xAxis'  [yAxis]='yAxis'
       [titleSettings]='titleSettings' [cellSettings]='cellSettings' (tooltipRender)='tooltipRender($event)'>
        </ejs-heatmap>`,
    encapsulation: ViewEncapsulation.None
})
export class AppComponent{

dataSource: Object[] = [
   [0.72, 0.71, 0.71, 0.67, 0.72, 0.53, 0.53, 0.56, 0.58, 0.56],
    [2.28, 2.29, 2.09, 1.84, 1.64, 1.49, 1.49, 1.39, 1.32, 1.23],
    [2.02, 2.17, 2.30, 2.39, 2.36, 2.52, 2.62, 2.57, 2.57, 2.74],
    [3.21, 3.26, 3.45, 3.47, 3.42, 3.34, 3.14, 2.83, 2.64, 2.61],
    [3.22, 3.13, 3.04, 2.95, 2.69, 2.49, 2.27, 2.18, 2.06, 1.87],
    [3.30, 3.39, 3.40, 3.48, 3.60, 3.67, 3.73, 3.79, 3.79, 4.07],
    [5.80, 5.74, 5.64, 5.44, 5.18, 5.08, 5.07, 5.00, 5.35, 5.47],
    [6.91, 7.40, 8.13, 8.80, 9.04, 9.24, 9.43, 9.35, 9.49, 9.69]];

     titleSettings: Object = {
            text: 'Crude Oil Production of Non-OPEC Countries (in Million barrels per day)',
            textStyle: {
                size: '15px',
                fontWeight: '500',
                fontStyle: 'Normal',
                fontFamily: 'Segoe UI'
            }
        };
        xAxis: Object = {
            labels: ['Canada', 'China', 'Egypt', 'Mexico', 'Norway', 'Russia', 'UK', 'USA']
        };
        yAxis: Object = {
             labels: ['2000', '2001', '2002', '2003', '2004', '2005', '2006', '2007', '2008', '2009', '2010'],
        };
        public cellSettings: Object = {
            showLabel: false,
        };
        public showTooltip: Boolean = true;
        public tooltipRender(args: ITooltipEventArgs): void {
            args.content = ['In ' + args.yLabel + ', the ' + args.xLabel + ' produced ' + args.value + ' million barrels per day'];
        };
 }
import { bootstrapApplication } from '@angular/platform-browser';
import { AppComponent } from './app.component';
import 'zone.js';
bootstrapApplication(AppComponent).catch((err) => console.error(err));

The fill and border properties are used to customize the background color and border of the tooltip respectively. The textStyle property in the tooltip is used to customize the font of the tooltip text.

app.component.ts
main.ts
import { NgModule } from '@angular/core'
import { BrowserModule } from '@angular/platform-browser'
import { HeatMapModule} from '@syncfusion/ej2-angular-heatmap'
import { TooltipService} from '@syncfusion/ej2-angular-heatmap'




import { Component, ViewEncapsulation } from '@angular/core';
import { ITooltipEventArgs } from '@syncfusion/ej2-angular-heatmap';

@Component({
imports: [
         HeatMapModule
    ],

providers: [TooltipService],
standalone: true,
    selector: 'my-app',
    template:
       `<ejs-heatmap id='container' style="display:block;" [dataSource]='dataSource' [xAxis]='xAxis'  [yAxis]='yAxis'
       [titleSettings]='titleSettings' [cellSettings]='cellSettings' [paletteSettings]='paletteSettings'  [tooltipSettings]='tooltipSettings' (tooltipRender)='tooltipRender($event)'>
        </ejs-heatmap>`,
    encapsulation: ViewEncapsulation.None
})
export class AppComponent{

dataSource: Object[] = [
   [0.72, 0.71, 0.71, 0.67, 0.72, 0.53, 0.53, 0.56, 0.58, 0.56],
    [2.28, 2.29, 2.09, 1.84, 1.64, 1.49, 1.49, 1.39, 1.32, 1.23],
    [2.02, 2.17, 2.30, 2.39, 2.36, 2.52, 2.62, 2.57, 2.57, 2.74],
    [3.21, 3.26, 3.45, 3.47, 3.42, 3.34, 3.14, 2.83, 2.64, 2.61],
    [3.22, 3.13, 3.04, 2.95, 2.69, 2.49, 2.27, 2.18, 2.06, 1.87],
    [3.30, 3.39, 3.40, 3.48, 3.60, 3.67, 3.73, 3.79, 3.79, 4.07],
    [5.80, 5.74, 5.64, 5.44, 5.18, 5.08, 5.07, 5.00, 5.35, 5.47],
    [6.91, 7.40, 8.13, 8.80, 9.04, 9.24, 9.43, 9.35, 9.49, 9.69]];

     titleSettings: Object = {
            text: 'Crude Oil Production of Non-OPEC Countries (in Million barrels per day)',
            textStyle: {
                size: '15px',
                fontWeight: '500',
                fontStyle: 'Normal',
                fontFamily: 'Segoe UI'
            }
        };
        xAxis: Object = {
            labels: ['Canada', 'China', 'Egypt', 'Mexico', 'Norway', 'Russia', 'UK', 'USA']
        };
        yAxis: Object = {
             labels: ['2000', '2001', '2002', '2003', '2004', '2005', '2006', '2007', '2008', '2009', '2010'],
        };
        public cellSettings: Object = {
            showLabel: false,
        };
        public paletteSettings: Object = {
                palette: [
                { color: '#F0ADCE'},
                { color: '#19307B'},
            ],
        };
        public tooltipSettings: Object = {
                fill: '#696295',
                 textStyle: {
                color: '#FFFFFF',
                size: '12px'
            },
             border: {
                width: 2,
                color: '#F0C27B'
            }
        };
        public showTooltip: Boolean = true;
        public tooltipRender(args: ITooltipEventArgs): void {
            args.content = ['In ' + args.yLabel + ', the ' + args.xLabel + ' produced ' + args.value + ' million barrels per day'];
        };
 }
import { bootstrapApplication } from '@angular/platform-browser';
import { AppComponent } from './app.component';
import 'zone.js';
bootstrapApplication(AppComponent).catch((err) => console.error(err));

Note: To use tooltip feature, we need to inject Tooltip using HeatMap.Inject(Tooltip).

Tooltip in Angular Heatmap chart component

Default tooltip

Tooltip template

Customize the appearance of Tooltip