Dynamic hierarchical data in EJ2 TypeScript ListView control

28 Jan 202511 minutes to read

To create a dynamic hierarchical ListView, push new list item data into the existing dataSource using the select event.

Refer to the following steps to load list items into the child list:

  1. Initially, render the ListView with the required data source.

  2. Bind the select event that triggers when selecting a list item in the ListView control. By using the select event, you can push new list items to the child list of the data source by specifying its item index. The item index can be obtained from the SelectEventArgs of the select event.

import { ListView, SelectEventArgs } from '@syncfusion/ej2-lists';

let dataSource: { [key: string]: Object }[] = [
    {
        id: '01', text: 'Music', icon: 'folder',
        child: [
            { id: '01-01', text: 'Gouttes.mp3', icon: 'file' }
        ]
    },
    {
        id: '02', text: 'Videos', icon: 'folder',
        child: [
            { id: '02-01', text: 'Naturals.mp4', icon: 'file' },
            { id: '02-02', text: 'Wild.mpeg', icon: 'file' }
        ]
    },
    {
        id: '03', text: 'Documents', icon: 'folder',
        child: [
            { id: '03-01', text: 'Environment Pollution.docx', icon: 'file' },
            { id: '03-02', text: 'Global Water, Sanitation, & Hygiene.docx', icon: 'file' },
            { id: '03-03', text: 'Global Warming.ppt', icon: 'file' },
            { id: '03-04', text: 'Social Network.pdf', icon: 'file' },
            { id: '03-05', text: 'Youth Empowerment.pdf', icon: 'file' }
        ]
    },
    {
        id: '04', text: 'Pictures', icon: 'folder',
        child: [
            {
                id: '04-01', text: 'Camera Roll', icon: 'folder',
                child: [
                    { id: '04-01-01', text: 'WIN_20160726_094117.JPG', icon: 'file' },
                    { id: '04-01-02', text: 'WIN_20160726_094118.JPG', icon: 'file' },
                    { id: '04-01-03', text: 'WIN_20160726_094119.JPG', icon: 'file' }
                ]
            },
            { id: '04-02', text: 'Wind.jpg', icon: 'file' },
            { id: '04-03', text: 'Stone.jpg', icon: 'file' },
            { id: '04-04', text: 'Home.jpg', icon: 'file' },
            { id: '04-05', text: 'Bridge.png', icon: 'file' }
        ]
    },
    {
        id: '05', text: 'Downloads', icon: 'folder',
        child: [
            { id: '05-01', text: 'UI-Guide.pdf', icon: 'file' },
            { id: '05-02', text: 'Tutorials.zip', icon: 'file' },
            { id: '05-03', text: 'Game.exe', icon: 'file' },
            { id: '05-04', text: 'TypeScript.7z', icon: 'file' }
        ]
    }
];
//Initialize the listview control
let listviewInstance: ListView = new ListView({

    //Set the defined data to the dataSource property
    dataSource: dataSource,

    //Map the appropriate columns to the fields property
    fields: { iconCss: 'icon', tooltip: 'text' },

    //Set the showIcon to true
    showIcon: true,

    //Set header title
    headerTitle: 'Folders',

    //Set the showHeader to true
    showHeader: true,

    //Select onSelect event to add new list item in child page
    select: onSelect
});

//Render the initialized ListView
listviewInstance.appendTo("#listview");

//Select event to add new list item in child page
function onSelect(args: SelectEventArgs) {
    //Add new file to the child page of selected list item
    this.dataSource[args.index].child.push({ id: '01-02', text: 'Newly Added File', icon: 'file', htmlAttributes: { role: 'li', class: 'list' } });
}
<!DOCTYPE html>
<html lang="en">

<head>
    <title>Essential JS 2 for ListView </title>
    <meta charset="utf-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <meta name="description" content="Essential JS 2 for ListView UI Control" />
    <meta name="author" content="Syncfusion" />
    <link href="index.css" rel="stylesheet" />
    <link href="https://cdn.syncfusion.com/ej2/30.1.37/ej2-base/styles/material.css" rel="stylesheet" />
    <link href="https://cdn.syncfusion.com/ej2/30.1.37/ej2-lists/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='listview'></div>
    </div>
    <style>
        #listview {
            display: block;
            max-width: 350px;
            margin: auto;
            border: 1px solid #dddddd;
            border-radius: 3px;
        }


        #listview.e-listview .e-list-icon {
            height: 24px;
            width: 30px;
        }

        .folder,
        .file {
            background: url('//ej2.syncfusion.com/demos/src/listview/images/file_icons.png') no-repeat;
            background-size: 302%;
        }

        .folder {
            background-position: -5px -466px;
        }

        .file {
            background-position: -5px -151px;
        }

        /* csslint ignore:start */

        .list {
            color: deeppink !important;
        }

        /* csslint ignore:end */
    </style>
</body>

</html>
#container {
    visibility: hidden;
}

#loader {
  color: #008cff;
  height: 40px;
  width: 30%;
  position: absolute;
  font-family: 'Helvetica Neue','calibiri';
  font-size: 14px;
  top: 45%;
  left: 45%;
}