Getting started with Angular Heatmap chart component

28 Sep 202324 minutes to read

This section explains the steps required to create a heat map and demonstrates the basic usage of the heat map control.

Setup Angular Environment

You can use Angular CLI to setup your Angular applications. To install Angular CLI use the following command.

npm install -g @angular/cli

Create an Angular Application

Start a new Angular application using below Angular CLI command.

ng new my-app
cd my-app

Installing Syncfusion Heatmap package

Syncfusion packages are distributed in npm as @syncfusion scoped packages. You can get all the Angular Syncfusion package from npm link.

Currently, Syncfusion provides two types of package structures for Angular components,

  1. Ivy library distribution package format
  2. Angular compatibility compiler(Angular’s legacy compilation and rendering pipeline) package.

Ivy library distribution package

Syncfusion Angular packages(>=20.2.36) has been moved to the Ivy distribution to support the Angular Ivy rendering engine and the package are compatible with Angular version 12 and above. To download the package use the below command.

Add @syncfusion/ej2-angular-heatmap package to the application.

npm install @syncfusion/ej2-angular-heatmap --save

Angular compatibility compiled package(ngcc)

For Angular version below 12, you can use the legacy (ngcc) package of the Syncfusion Angular components. To download the ngcc package use the below.

Add @syncfusion/ej2-angular-heatmap@ngcc package to the application.

npm install @syncfusion/ej2-angular-heatmap@ngcc --save

To mention the ngcc package in the package.json file, add the suffix -ngcc with the package version as below.

@syncfusion/ej2-angular-heatmap:"20.2.38-ngcc"

Note: If the ngcc tag is not specified while installing the package, the Ivy Library Package will be installed and this package will throw a warning.

Registering Heatmap Module

Import Heatmap module into Angular application(app.module.ts) from the package @syncfusion/ej2-ng-heatmap [src/app/app.module.ts].

  import { NgModule }      from '@angular/core';
  import { BrowserModule } from '@angular/platform-browser';
  // import the HeatMapModule for the heatmap component
  import { HeatMapModule } from '@syncfusion/ej2-angular-heatmap';
  import { AppComponent }  from './app.component';

  @NgModule({
    //declaration of ej2-ng-heatmap module into NgModule
    imports:      [ BrowserModule, HeatMapModule ],
    declarations: [ AppComponent ],
    bootstrap:    [ AppComponent ]
  })
  export class AppModule { }

Add Heatmap component

Modify the template in app.component.ts file to render the ej2-ng-heatmap component [src/app/app.component.ts].

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

  @Component({
    selector: 'my-app',
    // specifies the template string for the Heatmap component
    template: `<ejs-heatmap id='heatmap-container'></ejs-heatmap>`,
    encapsulation: ViewEncapsulation.None
  })
  export class AppComponent  { }

Now use the my-app in the index.html instead of default one.

  <my-app></my-app>

Use the npm run start command to run the application in the browser.

  npm start

The below example shows a basic Heatmap.

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

@Component({
    selector: 'my-app',
    // specifies the template string for the HeatMap component
    template: `<ejs-heatmap id="heatmap-container"></ejs-heatmap>`,
    encapsulation: ViewEncapsulation.None
})
export class AppComponent {

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

/**
 * Module
 */
@NgModule({
    imports: [
        BrowserModule, HeatMapModule
    ],
    declarations: [AppComponent],
    bootstrap: [AppComponent]
})
export class AppModule { }
import { platformBrowserDynamic } from '@angular/platform-browser-dynamic';
import { enableProdMode } from '@angular/core';
import { AppModule } from './app.module';

import 'zone.js';
enableProdMode();
platformBrowserDynamic().bootstrapModule(AppModule);

Module injection

The heat map components are segregated into individual feature-wise modules. To use its feature, you need to inject its feature module using the HeatMap.Inject() method. In the current application,the basic heat map is modified to visualize sales revenue data for week, and the tooltip and legend features of the heat map are used. Find the relevant feature modules and descriptions as follows.

  • LegendService - Provides the legend feature by injecting it.
  • TooltipService - Provides the tooltip feature by injecting it.

Now, import the above-mentioned modules from the heat map package and inject them into the heat map component as follows.

    import { NgModule } from '@angular/core';
    import { BrowserModule } from '@angular/platform-browser';
    import { AppComponent } from './app.component';
    import { HeatmapComponent, Legend, Tooltip } from '@syncfusion/ej2-ng-heatmap';

    @NgModule({
        imports: [
            BrowserModule,
        ],
        declarations: [AppComponent, HeatMapComponent],
        bootstrap: [AppComponent],
        providers: [ HeatmapComponent, LegendService, TooltipService ]
    })

Populate heat map with data

This section explains how to populate the following two-dimensional array data to the heat map.

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

@Component({
    selector: 'my-app',
    template:
       `<ejs-heatmap id='container' style="display:block;" [dataSource]='dataSource'>
        </ejs-heatmap>`,
    encapsulation: ViewEncapsulation.None
})
export class AppComponent{
        // Data for heatmap
         dataSource: Object[] = [
           [73, 39, 26, 39, 94, 0],
           [93, 58, 53, 38, 26, 68],
           [99, 28, 22, 4, 66, 90],
           [14, 26, 97, 69, 69, 3],
           [7, 46, 47, 47, 88, 6],
           [41, 55, 73, 23, 3, 79],
           [56, 69, 21, 86, 3, 33],
           [45, 7, 53, 81, 95, 79],
           [60, 77, 74, 68, 88, 51],
           [25, 25, 10, 12, 78, 14],
           [25, 56, 55, 58, 12, 82],
           [74, 33, 88, 23, 86, 59]
        ];
    }
import { NgModule } from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';
import { AppComponent } from './app.component';
import { HeatMapModule } from '@syncfusion/ej2-angular-heatmap';

/**
 * Module
 */
@NgModule({
    imports: [
        BrowserModule, HeatMapModule
    ],
    declarations: [AppComponent],
    bootstrap: [AppComponent]
})
export class AppModule { }
import { platformBrowserDynamic } from '@angular/platform-browser-dynamic';
import { enableProdMode } from '@angular/core';
import { AppModule } from './app.module';

import 'zone.js';
enableProdMode();
platformBrowserDynamic().bootstrapModule(AppModule);

Enable axis labels

You can add axis labels to the heat map and format those labels using the xAxis and yAxis properties. Axis labels provide additional information about the data points populated in the heat map.

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

@Component({
    selector: 'my-app',
    template:
       `<ejs-heatmap id='container' style="display:block;" [dataSource]='dataSource' [xAxis]='xAxis' [yAxis]='yAxis'>
        </ejs-heatmap>`,
    encapsulation: ViewEncapsulation.None
})
export class AppComponent{
        // Data for heatmap
        dataSource: Object[] = [
           [73, 39, 26, 39, 94, 0],
           [93, 58, 53, 38, 26, 68],
           [99, 28, 22, 4, 66, 90],
           [14, 26, 97, 69, 69, 3],
           [7, 46, 47, 47, 88, 6],
           [41, 55, 73, 23, 3, 79],
           [56, 69, 21, 86, 3, 33],
           [45, 7, 53, 81, 95, 79],
           [60, 77, 74, 68, 88, 51],
           [25, 25, 10, 12, 78, 14],
           [25, 56, 55, 58, 12, 82],
           [74, 33, 88, 23, 86, 59]
        ];
        xAxis: Object = {
        labels: ['Nancy', 'Andrew', 'Janet', 'Margaret', 'Steven', 'Michael', 'Robert',
            'Laura', 'Anne', 'Paul', 'Karin', 'Mario'],
    };
    yAxis: Object = {
        labels: ['Mon', 'Tues', 'Wed', 'Thurs', 'Fri', 'Sat'],
    };
}
import { NgModule } from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';
import { AppComponent } from './app.component';
import { HeatMapModule} from '@syncfusion/ej2-angular-heatmap';

/**
 * Module
 */
@NgModule({
    imports: [
        BrowserModule, HeatMapModule
    ],
    declarations: [AppComponent],
    bootstrap: [AppComponent]
})
export class AppModule { }
import { platformBrowserDynamic } from '@angular/platform-browser-dynamic';
import { enableProdMode } from '@angular/core';
import { AppModule } from './app.module';

import 'zone.js';
enableProdMode();
platformBrowserDynamic().bootstrapModule(AppModule);

Add heat map title

Add a title using the titleSettings property to the heat map to provide quick information to the user about the data populated in the heat map.

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

@Component({
    selector: 'my-app',
    template:
       `<ejs-heatmap id='container' style="display:block;"  [titleSettings]='titleSettings' [dataSource]='dataSource' [xAxis]='xAxis' [yAxis]='yAxis'>
        </ejs-heatmap>`,
    encapsulation: ViewEncapsulation.None
})
export class AppComponent{
     titleSettings: Object = {
        text: 'Sales Revenue per Employee (in 1000 US$)',
        textStyle: {
            size: '15px',
            fontWeight: '500',
            fontStyle: 'Normal'
        }
    };
        // Data for heatmap
         dataSource: Object[] = [
           [73, 39, 26, 39, 94, 0],
           [93, 58, 53, 38, 26, 68],
           [99, 28, 22, 4, 66, 90],
           [14, 26, 97, 69, 69, 3],
           [7, 46, 47, 47, 88, 6],
           [41, 55, 73, 23, 3, 79],
           [56, 69, 21, 86, 3, 33],
           [45, 7, 53, 81, 95, 79],
           [60, 77, 74, 68, 88, 51],
           [25, 25, 10, 12, 78, 14],
           [25, 56, 55, 58, 12, 82],
           [74, 33, 88, 23, 86, 59]
        ];
        xAxis: Object = {
        labels: ['Nancy', 'Andrew', 'Janet', 'Margaret', 'Steven', 'Michael', 'Robert',
            'Laura', 'Anne', 'Paul', 'Karin', 'Mario'],
    };
    yAxis: Object = {
        labels: ['Mon', 'Tues', 'Wed', 'Thurs', 'Fri', 'Sat'],
    };
}
import { NgModule } from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';
import { AppComponent } from './app.component';
import { HeatMapModule} from '@syncfusion/ej2-angular-heatmap';
/**
 * Module
 */
@NgModule({
    imports: [
        BrowserModule, HeatMapModule
    ],
    declarations: [AppComponent],
    bootstrap: [AppComponent]
})
export class AppModule { }
import { platformBrowserDynamic } from '@angular/platform-browser-dynamic';
import { enableProdMode } from '@angular/core';
import { AppModule } from './app.module';

import 'zone.js';
enableProdMode();
platformBrowserDynamic().bootstrapModule(AppModule);

Enable legend

Use a legend for the heat map in the legendSettings object by setting the visible property to true and injecting the Legend module using the HeatMap.Inject(Legend) method.

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

@Component({
    selector: 'my-app',
    template:
       `<ejs-heatmap id='container' style="display:block;"  [titleSettings]='titleSettings' [dataSource]='dataSource'
       [xAxis]='xAxis' [yAxis]='yAxis' [legendSettings]='legendSettings'>
        </ejs-heatmap>`,
    encapsulation: ViewEncapsulation.None
})
export class AppComponent{
     titleSettings: Object = {
        text: 'Sales Revenue per Employee (in 1000 US$)',
        textStyle: {
            size: '15px',
            fontWeight: '500',
            fontStyle: 'Normal'
        }
    };
        // Data for heatmap
         dataSource: Object[] = [
           [73, 39, 26, 39, 94, 0],
           [93, 58, 53, 38, 26, 68],
           [99, 28, 22, 4, 66, 90],
           [14, 26, 97, 69, 69, 3],
           [7, 46, 47, 47, 88, 6],
           [41, 55, 73, 23, 3, 79],
           [56, 69, 21, 86, 3, 33],
           [45, 7, 53, 81, 95, 79],
           [60, 77, 74, 68, 88, 51],
           [25, 25, 10, 12, 78, 14],
           [25, 56, 55, 58, 12, 82],
           [74, 33, 88, 23, 86, 59]
        ];
        xAxis: Object = {
        labels: ['Nancy', 'Andrew', 'Janet', 'Margaret', 'Steven', 'Michael', 'Robert',
            'Laura', 'Anne', 'Paul', 'Karin', 'Mario'],
    };
    yAxis: Object = {
        labels: ['Mon', 'Tues', 'Wed', 'Thurs', 'Fri', 'Sat'],
    };
    public legendSettings: Object = {
        visible:true,
        position: 'Right',
        showLabel:true,
        height:'150px'
    };
}
import { NgModule } from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';
import { AppComponent } from './app.component';
import { HeatMapModule, LegendService } from '@syncfusion/ej2-angular-heatmap';

/**
 * Module
 */
@NgModule({
    imports: [
        BrowserModule, HeatMapModule
    ],
    declarations: [AppComponent],
    bootstrap: [AppComponent],
    providers: [LegendService]
})
export class AppModule { }
import { platformBrowserDynamic } from '@angular/platform-browser-dynamic';
import { enableProdMode } from '@angular/core';
import { AppModule } from './app.module';

import 'zone.js';
enableProdMode();
platformBrowserDynamic().bootstrapModule(AppModule);

Add data label

Add data labels to improve the readability of the heat map. This can be achieved by setting the showLabel property to true in the cellSettings object.

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

@Component({
    selector: 'my-app',
    template:
       `<ejs-heatmap id='container' style="display:block;" [cellSettings]='cellSettings' [titleSettings]='titleSettings' [dataSource]='dataSource'
       [xAxis]='xAxis' [yAxis]='yAxis' [legendSettings]='legendSettings'>
        </ejs-heatmap>`,
    encapsulation: ViewEncapsulation.None
})
export class AppComponent{
     titleSettings: Object = {
        text: 'Sales Revenue per Employee (in 1000 US$)',
        textStyle: {
            size: '15px',
            fontWeight: '500',
            fontStyle: 'Normal'
        }
    };
        // Data for heatmap
         dataSource: Object[] = [
           [73, 39, 26, 39, 94, 0],
           [93, 58, 53, 38, 26, 68],
           [99, 28, 22, 4, 66, 90],
           [14, 26, 97, 69, 69, 3],
           [7, 46, 47, 47, 88, 6],
           [41, 55, 73, 23, 3, 79],
           [56, 69, 21, 86, 3, 33],
           [45, 7, 53, 81, 95, 79],
           [60, 77, 74, 68, 88, 51],
           [25, 25, 10, 12, 78, 14],
           [25, 56, 55, 58, 12, 82],
           [74, 33, 88, 23, 86, 59]
        ];
        xAxis: Object = {
        labels: ['Nancy', 'Andrew', 'Janet', 'Margaret', 'Steven', 'Michael', 'Robert',
            'Laura', 'Anne', 'Paul', 'Karin', 'Mario'],
    };
    yAxis: Object = {
        labels: ['Mon', 'Tues', 'Wed', 'Thurs', 'Fri', 'Sat'],
    };
    public legendSettings: Object = {
        visible:true,
        position: 'Right',
        showLabel:true,
        height:'150px'
    };
    public cellSettings: Object = {
        showLabel: true,
    };
}
import { NgModule } from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';
import { AppComponent } from './app.component';
import { HeatMapModule, LegendService } from '@syncfusion/ej2-angular-heatmap';

/**
 * Module
 */
@NgModule({
    imports: [
        BrowserModule, HeatMapModule
    ],
    declarations: [AppComponent],
    bootstrap: [AppComponent],
    providers: [ LegendService]
})
export class AppModule { }
import { platformBrowserDynamic } from '@angular/platform-browser-dynamic';
import { enableProdMode } from '@angular/core';
import { AppModule } from './app.module';

import 'zone.js';
enableProdMode();
platformBrowserDynamic().bootstrapModule(AppModule);

Add custom cell palette

The default palette settings of the heat map cells can be customized by using the paletteSettings property. Using the palette property in paletteSettings object, you can change the color set for the cells. You can change the color mode of the cells to fixed or gradient mode using the type property.

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

@Component({
    selector: 'my-app',
    template:
       `<ejs-heatmap id='container' style="display:block;" [paletteSettings]='paletteSettings'
       [cellSettings]='cellSettings' [titleSettings]='titleSettings' [dataSource]='dataSource'
       [xAxis]='xAxis' [yAxis]='yAxis' [legendSettings]='legendSettings'>
        </ejs-heatmap>`,
    encapsulation: ViewEncapsulation.None
})
export class AppComponent{
     titleSettings: Object = {
        text: 'Sales Revenue per Employee (in 1000 US$)',
        textStyle: {
            size: '15px',
            fontWeight: '500',
            fontStyle: 'Normal'
        }
    };
        // Data for heatmap
         dataSource: Object[] = [
           [73, 39, 26, 39, 94, 0],
           [93, 58, 53, 38, 26, 68],
           [99, 28, 22, 4, 66, 90],
           [14, 26, 97, 69, 69, 3],
           [7, 46, 47, 47, 88, 6],
           [41, 55, 73, 23, 3, 79],
           [56, 69, 21, 86, 3, 33],
           [45, 7, 53, 81, 95, 79],
           [60, 77, 74, 68, 88, 51],
           [25, 25, 10, 12, 78, 14],
           [25, 56, 55, 58, 12, 82],
           [74, 33, 88, 23, 86, 59]
        ];
        xAxis: Object = {
        labels: ['Nancy', 'Andrew', 'Janet', 'Margaret', 'Steven', 'Michael', 'Robert',
            'Laura', 'Anne', 'Paul', 'Karin', 'Mario'],
    };
    yAxis: Object = {
        labels: ['Mon', 'Tues', 'Wed', 'Thurs', 'Fri', 'Sat'],
    };
    public legendSettings: Object = {
        visible:true,
        position: 'Right',
        showLabel:true,
        height:'150px'
    };
    public cellSettings: Object = {
        showLabel: true,
    };
     public paletteSettings: Object = {
        palette: [{ value: 0, color: '#C06C84' },
        { value: 50, color: '#6C5B7B' },
        { value: 100, color: '#355C7D' },
        ]
    };
}
import { NgModule } from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';
import { AppComponent } from './app.component';
import { HeatMapModule, LegendService } from '@syncfusion/ej2-angular-heatmap';

/**
 * Module
 */
@NgModule({
    imports: [
        BrowserModule, HeatMapModule
    ],
    declarations: [AppComponent],
    bootstrap: [AppComponent],
    providers: [LegendService]
})
export class AppModule { }
import { platformBrowserDynamic } from '@angular/platform-browser-dynamic';
import { enableProdMode } from '@angular/core';
import { AppModule } from './app.module';

import 'zone.js';
enableProdMode();
platformBrowserDynamic().bootstrapModule(AppModule);

Enable tooltip

The tooltip is used when you cannot display information by using the data labels due to space constraints. You can enable the tooltip by setting the showTooltip property to true and injecting the Tooltip module using the HeatMap.Inject(Tooltip) method.

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

@Component({
    selector: 'my-app',
    template:
       `<ejs-heatmap id='container' style="display:block;" showTooltip='true' [paletteSettings]='paletteSettings'
       [cellSettings]='cellSettings' [titleSettings]='titleSettings' [dataSource]='dataSource'
       [xAxis]='xAxis' [yAxis]='yAxis' [legendSettings]='legendSettings'>
        </ejs-heatmap>`,
    encapsulation: ViewEncapsulation.None
})
export class AppComponent{
     titleSettings: Object = {
        text: 'Sales Revenue per Employee (in 1000 US$)',
        textStyle: {
            size: '15px',
            fontWeight: '500',
            fontStyle: 'Normal'
        }
    };
        // Data for heatmap
         dataSource: Object[] = [
           [73, 39, 26, 39, 94, 0],
           [93, 58, 53, 38, 26, 68],
           [99, 28, 22, 4, 66, 90],
           [14, 26, 97, 69, 69, 3],
           [7, 46, 47, 47, 88, 6],
           [41, 55, 73, 23, 3, 79],
           [56, 69, 21, 86, 3, 33],
           [45, 7, 53, 81, 95, 79],
           [60, 77, 74, 68, 88, 51],
           [25, 25, 10, 12, 78, 14],
           [25, 56, 55, 58, 12, 82],
           [74, 33, 88, 23, 86, 59]
        ];
        xAxis: Object = {
        labels: ['Nancy', 'Andrew', 'Janet', 'Margaret', 'Steven', 'Michael', 'Robert',
            'Laura', 'Anne', 'Paul', 'Karin', 'Mario'],
    };
    yAxis: Object = {
        labels: ['Mon', 'Tues', 'Wed', 'Thurs', 'Fri', 'Sat'],
    };
    public legendSettings: Object = {
        visible:true,
        position: 'Right',
        showLabel:true,
        height:'150px'
    };
    public cellSettings: Object = {
        showLabel: true,
    };
     public paletteSettings: Object = {
        palette: [{ value: 0, color: '#C06C84' },
        { value: 50, color: '#6C5B7B' },
        { value: 100, color: '#355C7D' },
        ]
    };
}
import { NgModule } from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';
import { AppComponent } from './app.component';
import { HeatMapModule} from '@syncfusion/ej2-angular-heatmap';
import { LegendService, TooltipService} from '@syncfusion/ej2-angular-heatmap';

/**
 * Module
 */
@NgModule({
    imports: [
        BrowserModule, HeatMapModule
    ],
    declarations: [AppComponent],
    bootstrap: [AppComponent],
    providers: [ LegendService, TooltipService]
})
export class AppModule { }
import { platformBrowserDynamic } from '@angular/platform-browser-dynamic';
import { enableProdMode } from '@angular/core';
import { AppModule } from './app.module';

import 'zone.js';
enableProdMode();
platformBrowserDynamic().bootstrapModule(AppModule);

You can refer to our Angular Heatmap Chart feature tour page for its groundbreaking feature representations. You can also explore our Angular Heatmap Chart example that shows how to render the Heatmap Chart in Angular.