Getting started with Angular Check box component

14 Nov 20226 minutes to read

This section explains how to create a simple CheckBox, and demonstrate the basic usage of the CheckBox module in an Angular environment.

Dependencies

The following list of dependencies are required to use the CheckBox module in your application.

|-- @syncfusion/ej2-angular-buttons
    |-- @syncfusion/ej2-angular-base
    |-- @syncfusion/ej2-base
    |-- @syncfusion/ej2-buttons

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 CheckBox 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-buttons package to the application.

npm install @syncfusion/ej2-angular-buttons --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-buttons@ngcc package to the application.

npm install @syncfusion/ej2-angular-buttons@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-buttons:"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.

Adding CheckBox module

Import CheckBox module into Angular application(app.module.ts) from the package
@syncfusion/ej2-angular-buttons.

import { NgModule }      from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';

// Imported Syncfusion checkbox module from buttons package.
import { CheckBoxModule } from '@syncfusion/ej2-angular-buttons';

import { AppComponent }  from './app.component';

@NgModule({
  imports:      [ BrowserModule, CheckBoxModule ], // Registering EJ2 Checkbox Module.
  declarations: [ AppComponent ],
  bootstrap:    [ AppComponent ]
})
export class AppModule { }

Adding Syncfusion CheckBox component

Modify the template in app.component.ts file to render the CheckBox component.

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

@Component({
  selector: 'app-root',
  template: `<!-- To Render CheckBox. -->
             <ejs-checkbox label="Default"></ejs-checkbox>`
})
export class AppComponent  { }

Adding CSS reference

Add CheckBox component’s styles as given below in style.css.

@import '../node_modules/@syncfusion/ej2-base/styles/material.css';
@import '../node_modules/@syncfusion/ej2-buttons/styles/material.css';

Running the application

Run the application in the browser using the following command:

ng serve

The below example shows a basic CheckBox component,

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

@Component({
    selector: 'app-root',
    template: `<!-- To Render CheckBox. -->
               <ejs-checkbox label="Default"></ejs-checkbox>`
})

export class AppComponent { }
import { NgModule } from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';
import { CheckBoxModule } from '@syncfusion/ej2-angular-buttons';
import { AppComponent } from './app.component';
import { enableRipple } from '@syncfusion/ej2-base';

enableRipple(true);

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

enableProdMode();
platformBrowserDynamic().bootstrapModule(AppModule);

Change the CheckBox state

The Essential JS 2 CheckBox contains 3 different states visually, they are:

  • Checked
  • Unchecked
  • Indeterminate

The CheckBox checked property is used to handle the checked and unchecked state.
In checked state a tick mark will be added to the visualization of CheckBox.

Indeterminate

CheckBox indeterminate state can be set through indeterminate property. CheckBox indeterminate state masks the real value of CheckBox visually. Checkbox cannot be changed to indeterminate state through the user interface, this state can be achieved only through the property.

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

@Component({
    selector: 'app-root',
    template: `<ul>
               <!-- checked state. -->
               <li><ejs-checkbox label="Checked State" [checked]="true"></ejs-checkbox></li>

               <!-- unchecked state. -->
               <li><ejs-checkbox label="Unchecked State"></ejs-checkbox></li>

               <!-- indeterminate state. -->
               <li><ejs-checkbox label="Indeterminate State" [indeterminate]="true"></ejs-checkbox></li>
               </ul>`
})

export class AppComponent { }
import { NgModule } from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';
import { CheckBoxModule } from '@syncfusion/ej2-angular-buttons';
import { AppComponent } from './app.component';
import { enableRipple } from '@syncfusion/ej2-base';

enableRipple(true);

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

enableProdMode();
platformBrowserDynamic().bootstrapModule(AppModule);