Getting started in EJ2 TypeScript Treeview control

3 Nov 202311 minutes to read

This section explains the steps required to create a simple JavaScript TreeView component, and configure its available functionalities in TypeScript using the Essential JS 2 quickstart seed repository. This seed repository is preconfigured with all the Essential JS 2 packages.

This application is integrated with the webpack.config.js configuration and uses the latest version of the webpack-cli. It requires node v14.15.0 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 TreeView component in your application.

|-- @syncfusion/ej2-navigations
    |-- @syncfusion/ej2-base
    |-- @syncfusion/ej2-data
    |-- @syncfusion/ej2-lists
    |-- @syncfusion/ej2-inputs
    |-- @syncfusion/ej2-popups
        |-- @syncfusion/ej2-buttons

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

Combined CSS files are available in the Essential JS 2 package root folder. This can be referenced in the ~/src/styles/styles.css file of your application using the following code.

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

To refer individual component CSS, please refer to the Individual Component theme files section. If you want to refer the combined component styles, please make use of our CRG (Custom Resource Generator) in your application.

Adding TreeView component

Now, you can start adding Essential JS 2 TreeView component to the application. To get started, add the TreeView component to app.ts and index.html files using the following code. Then, add the HTML <div> element with its id attribute set to tree for TreeView component to your index.html.

[src/index.html]

<!DOCTYPE html>
<html lang="en">

<head>
    <title>Essential JS 2 for TreeView</title>
    <meta charset="utf-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <meta name="description" content="Essential JS 2 for TreeView UI Control" />
    <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 id='loader'>Loading....</div>
    <div id='container'>
        <div id='treeparent'>
            <div id="tree"></div>
        </div>
    </div>
</body>

</html>

Place the following TreeView code in app.ts.

[src/app/app.ts]

import { enableRipple } from '@syncfusion/ej2-base';
enableRipple(true);
import { TreeView } from '@syncfusion/ej2-navigations'

//Initialize TreeView component
let treeViewInstance: TreeView = new TreeView();

//Render initialized TreeView
treeViewInstance.appendTo("#tree");

Binding data source

TreeView can load data either from local data sources or remote data services. This can be done using the dataSource property that is a member of the fields property. The dataSource property supports array of JavaScript objects and DataManager. Here, an array of JSON values is passed to the TreeView component.

[src/app/app.ts]

import { enableRipple } from '@syncfusion/ej2-base';
enableRipple(true);
import { TreeView } from '@syncfusion/ej2-navigations';

//define the array of JSON
let data: { [key: string]: Object }[] = [
    {
        nodeId: '01', nodeText: 'Music',
        nodeChild: [
            { nodeId: '01-01', nodeText: 'Gouttes.mp3' }
        ]
    },
    {
        nodeId: '02', nodeText: 'Videos', expanded: true,
        nodeChild: [
            { nodeId: '02-01', nodeText: 'Naturals.mp4' },
            { nodeId: '02-02', nodeText: 'Wild.mpeg' },
        ]
    },
    {
        nodeId: '03', nodeText: 'Documents',
        nodeChild: [
            { nodeId: '03-01', nodeText: 'Environment Pollution.docx' },
            { nodeId: '03-02', nodeText: 'Global Water, Sanitation, & Hygiene.docx' },
            { nodeId: '03-03', nodeText: 'Global Warming.ppt' },
            { nodeId: '03-04', nodeText: 'Social Network.pdf' },
            { nodeId: '03-05', nodeText: 'Youth Empowerment.pdf' },
        ]
    },
];
//Initialize TreeView component
let treeViewInstance: TreeView = new TreeView({
    fields: { dataSource: data, id: 'nodeId', text: 'nodeText', child: 'nodeChild' }
});

//Render initialized TreeView
treeViewInstance.appendTo("#tree");

Run the application

You have to use the npm start command to run the application in the browser.

npm start
import { enableRipple } from '@syncfusion/ej2-base';
enableRipple(true);
import { TreeView } from '@syncfusion/ej2-navigations';

//define the array of JSON
let data: { [key: string]: Object }[] = [
    {
        nodeId: '01', nodeText: 'Music',
        nodeChild: [
            { nodeId: '01-01', nodeText: 'Gouttes.mp3' }
        ]
    },
    {
        nodeId: '02', nodeText: 'Videos', expanded: true,
        nodeChild: [
            { nodeId: '02-01', nodeText: 'Naturals.mp4' },
            { nodeId: '02-02', nodeText: 'Wild.mpeg' },
        ]
    },
    {
        nodeId: '03', nodeText: 'Documents',
        nodeChild: [
            { nodeId: '03-01', nodeText: 'Environment Pollution.docx' },
            { nodeId: '03-02', nodeText: 'Global Water, Sanitation, & Hygiene.docx' },
            { nodeId: '03-03', nodeText: 'Global Warming.ppt' },
            { nodeId: '03-04', nodeText: 'Social Network.pdf' },
            { nodeId: '03-05', nodeText: 'Youth Empowerment.pdf' },
        ]
    },
];
//Initialize TreeView component
let treeViewInstance: TreeView = new TreeView({
    fields: { dataSource: data, id: 'nodeId', text: 'nodeText', child: 'nodeChild' }
});

//Render initialized TreeView
treeViewInstance.appendTo("#tree");
<!DOCTYPE html>
<html lang="en">

<head>
    <title>Essential JS 2 for TreeView </title>
    <meta charset="utf-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <meta name="description" content="Essential JS 2 for TreeView UI Control" />
    <meta name="author" content="Syncfusion" />
    <link href="index.css" rel="stylesheet" />
    <link href="https://cdn.syncfusion.com/ej2/23.2.4/ej2-base/styles/material.css" rel="stylesheet" />
    <link href="https://cdn.syncfusion.com/ej2/23.2.4/ej2-navigations/styles/material.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'>
        <div id='treeparent'>
            <div id="tree"></div>
        </div>
    </div>
</body>

</html>

You can also explore our JavaScript TreeView example to knows how to present and manipulate data.