Getting started in EJ2 TypeScript Check box control
3 Nov 20239 minutes to read
This section explains how to create a simple CheckBox, and configure its available functionalities in TypeScript, using Essential JS 2 quickstart seed repository.
This application is integrated with the
webpack.config.js
configuration and uses the latest version of the webpack-cli. It requires nodev14.15.0
or higher. For more information about webpack and its features, refer to the webpack documentation.
Dependencies
The following list of dependencies are required to use the CheckBox component in your application the.
|-- @syncfusion/ej2-buttons
|-- @syncfusion/ej2-base
Set up development environment
Open the command prompt from the required directory, and run the following command to clone the Syncfusion JavaScript (Essential JS 2) quickstart project from GitHub.
git clone https://github.com/SyncfusionExamples/ej2-quickstart-webpack- ej2-quickstart
After cloning the application in the ej2-quickstart
folder, run the following command line to navigate to the ej2-quickstart
folder.
cd ej2-quickstart
Add Syncfusion JavaScript packages
Syncfusion JavaScript (Essential JS 2) packages are available on the npmjs.com public registry. You can install all Syncfusion JavaScript (Essential JS 2) controls in a single @syncfusion/ej2 package or individual packages for each control.
The quickstart application is preconfigured with the dependent @syncfusion/ej2 package in the ~/package.json
file. Use the following command to install the dependent npm packages from the command prompt.
npm install
Import the Syncfusion CSS styles
To render Checkbox component, need to import Button and its dependent components styles as given below in the ~/src/styles/styles.css
file, as shown below:
@import "../../node_modules/@syncfusion/ej2-base/styles/material.css";
@import "../../node_modules/@syncfusion/ej2-buttons/styles/material.css";
Add CheckBox to the project
Add the HTML input tag with id attribute as the element
to your index.html
file.
[src/index.html]
<!DOCTYPE html>
<html lang="en">
<head>
<title>Essential JS 2</title>
<meta charset="utf-8" />
<meta name="viewport" content="width=device-width, initial-scale=1.0, user-scalable=no" />
<meta name="description" content="Essential JS 2" />
<meta name="author" content="Syncfusion" />
<link rel="shortcut icon" href="resources/favicon.ico" />
<link href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css" rel="stylesheet" />
</head>
<body>
<div>
<!--element which is going to render-->
<input id="element" type="checkbox"/>
</div>
</body>
</html>
Import the CheckBox component in your app.ts
file and initialize it to #element
as shown in the following.
[src/app/app.ts]
import { CheckBox } from '@syncfusion/ej2-buttons';
// Initialize CheckBox component.
let checkbox: CheckBox = new CheckBox({ label: 'Default' });
// Render initialized CheckBox.
checkbox.appendTo('#element');
Run the application
Run the application in the browser using the following command:
npm start
The following example shows a basic CheckBox component.
import { CheckBox } from '@syncfusion/ej2-buttons';
import { enableRipple } from '@syncfusion/ej2-base';
enableRipple(true);
// Initialize CheckBox component.
let checkbox: CheckBox = new CheckBox({ label: 'Default' });
// Render initialized CheckBox.
checkbox.appendTo('#element');
<!DOCTYPE html>
<html lang="en">
<head>
<title>EJ2 CheckBox</title>
<meta charset="utf-8" />
<meta name="viewport" content="width=device-width, initial-scale=1.0" />
<meta name="description" content="Typescript UI Controls" />
<meta name="author" content="Syncfusion" />
<link href="https://cdn.syncfusion.com/ej2/27.1.48/ej2-base/styles/material.css" rel="stylesheet" />
<link href="https://cdn.syncfusion.com/ej2/27.1.48/ej2-buttons/styles/material.css" rel="stylesheet" />
<link href="styles.css" rel="stylesheet" />
<script src="https://cdnjs.cloudflare.com/ajax/libs/systemjs/0.19.38/system.js"></script>
<script src="systemjs.config.js"></script>
<script src="https://cdn.syncfusion.com/ej2/syncfusion-helper.js" type ="text/javascript"></script>
</head>
<body>
<div id='loader'>LOADING....</div>
<div id='container'>
<input type='checkbox' id='element'/>
</div>
</body>
</html>
#container {
visibility: hidden;
}
#loader {
color: #008cff;
height: 40px;
width: 30%;
position: absolute;
top: 45%;
left: 45%;
}
.e-checkbox-wrapper {
margin-top: 18px;
}
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
The CheckBox indeterminate state can be set through indeterminate
property. CheckBox indeterminate state masks the real value of CheckBox visually. The Checkbox cannot be changed to indeterminate state through the user interface, this state can be achieved only through the property.
import { CheckBox } from '@syncfusion/ej2-buttons';
import { enableRipple } from '@syncfusion/ej2-base';
enableRipple(true);
//checked state.
let checkbox: CheckBox = new CheckBox({ label: 'Checked State', checked: true });
checkbox.appendTo('#checkbox1');
//unchecked state.
checkbox = new CheckBox({ label: 'Unchecked State' });
checkbox.appendTo('#checkbox2');
//indeterminate state.
checkbox = new CheckBox({ label: 'Indeterminate State', indeterminate: true });
checkbox.appendTo('#checkbox3');
<!DOCTYPE html>
<html lang="en">
<head>
<title>EJ2 CheckBox</title>
<meta charset="utf-8" />
<meta name="viewport" content="width=device-width, initial-scale=1.0" />
<meta name="description" content="Typescript UI Controls" />
<meta name="author" content="Syncfusion" />
<link href="https://cdn.syncfusion.com/ej2/27.1.48/ej2-base/styles/material.css" rel="stylesheet" />
<link href="https://cdn.syncfusion.com/ej2/27.1.48/ej2-buttons/styles/material.css" rel="stylesheet" />
<link href="styles.css" rel="stylesheet" />
<script src="https://cdnjs.cloudflare.com/ajax/libs/systemjs/0.19.38/system.js"></script>
<script src="systemjs.config.js"></script>
<script src="https://cdn.syncfusion.com/ej2/syncfusion-helper.js" type ="text/javascript"></script>
</head>
<body>
<div id='loader'>LOADING....</div>
<div id='container'>
<ul>
<li><input type="checkbox" id="checkbox1" /></li>
<li><input type="checkbox" id="checkbox2" /></li>
<li><input type="checkbox" id="checkbox3" /></li>
</ul>
</div>
</body>
</html>
#container {
visibility: hidden;
}
#loader {
color: #008cff;
height: 40px;
width: 30%;
position: absolute;
top: 45%;
left: 45%;
}
.e-checkbox-wrapper {
margin-top: 18px;
}
li {
list-style: none;
}