Templates in EJ2 TypeScript Dropdown Tree Control

27 Feb 202524 minutes to read

The Dropdown Tree control provides support to customize each list item, header, and footer elements. It uses the Essential JS 2 Template engine to compile and render the elements properly.

Item template

The content of each list item within the Dropdown Tree control can be customized using the itemTemplate property.

In the following sample, Dropdown Tree list items are customized with employee information such as name and job using the itemTemplate property.

The template expression should be provided inside the ${…} interpolation syntax.

import { DropDownTree } from '@syncfusion/ej2-dropdowns';

let data: { [key: string]: Object }[] = [
    { "id": 1, "name": "Steven Buchanan", "job": "General Manager", "hasChild": true, "expanded": true },
    { "id": 2, "pid": 1, "name": "Laura Callahan", "job": "Product Manager", "hasChild": true },
    { "id": 3, "pid": 2, "name": "Andrew Fuller", "job": "Team Lead", "hasChild": true },
    { "id": 4, "pid": 3, "name": "Anne Dodsworth", "job": "Developer" },
    { "id": 10, "pid": 3, "name": "Lilly", "job": "Developer", "status": "online" },
    { "id": 5, "pid": 1, "name": "Nancy Davolio", "job": "Product Manager", "hasChild": true },
    { "id": 6, "pid": 5, "name": "Michael Suyama", "job": "Team Lead", "hasChild": true },
    { "id": 7, "pid": 6, "name": "Robert King", "job": "Developer " },
    { "id": 11, "pid": 6, "name": "Mary", "job": "Developer " },
    { "id": 9, "pid": 1, "name": "Janet Leverling", "job": "HR" }
];
let ddtreeObj: DropDownTree = new DropDownTree({
    fields: { dataSource: data, text: 'name', value: 'id', parentValue: 'pid', hasChildren: 'hasChild' },
    itemTemplate: '#itemTemplate',
    width: '100%',
    cssClass: 'custom',
    placeholder: 'Select an employee',
    popupHeight: '250px'
});
ddtreeObj.appendTo('#template');
<!DOCTYPE html>
<html lang="en">

<head>
    <title>Essential JS 2 Dropdown Tree</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/ej2/29.1.33/ej2-base/styles/material.css" rel="stylesheet" />
    <link href="https://cdn.syncfusion.com/ej2/29.1.33/ej2-inputs/styles/material.css" rel="stylesheet" />
    <link href="https://cdn.syncfusion.com/ej2/29.1.33/ej2-buttons/styles/material.css" rel="stylesheet" />
    <link href="https://cdn.syncfusion.com/ej2/29.1.33/ej2-lists/styles/material.css" rel="stylesheet" />
    <link href="https://cdn.syncfusion.com/ej2/29.1.33/ej2-navigations/styles/material.css" rel="stylesheet" />
    <link href="https://cdn.syncfusion.com/ej2/29.1.33/ej2-dropdowns/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 class="stackblitz-container bootstrap5">
        <div class="col-lg-12 control-section">
            <div style="margin: 0 auto; max-width:350px;">
                <input type="text" id="template">
            </div>
        </div>
        <script id="itemTemplate" type="text/x-template">
            <div>     
                <span class="ename">${name} - </span>
                <span class="ejob">${job}</span> 
            </div>
        </script>
    </div>
    <style>
        .custom .ejob {
            opacity: .60;
        }
    </style>
</body>
</html>

Value template

The currently selected value displayed by default on the Dropdown Tree input element can be customized using the valueTemplate property.

In the following sample, the selected value is displayed as a combined text of both Name and Job in the Dropdown Tree input, separated by a hyphen.

import { DropDownTree } from '@syncfusion/ej2-dropdowns';

let data: { [key: string]: Object }[] = [
    { "id": 1, "name": "Steven Buchanan", "job": "General Manager", "hasChild": true, "expanded": true },
    { "id": 2, "pid": 1, "name": "Laura Callahan", "job": "Product Manager", "hasChild": true },
    { "id": 3, "pid": 2, "name": "Andrew Fuller", "job": "Team Lead", "hasChild": true },
    { "id": 4, "pid": 3, "name": "Anne Dodsworth", "job": "Developer" },
    { "id": 10, "pid": 3, "name": "Lilly", "job": "Developer", "status": "online" },
    { "id": 5, "pid": 1, "name": "Nancy Davolio", "job": "Product Manager", "hasChild": true },
    { "id": 6, "pid": 5, "name": "Michael Suyama", "job": "Team Lead", "hasChild": true },
    { "id": 7, "pid": 6, "name": "Robert King", "job": "Developer " },
    { "id": 11, "pid": 6, "name": "Mary", "job": "Developer " },
    { "id": 9, "pid": 1, "name": "Janet Leverling", "job": "HR" }
];
let ddtreeObj: DropDownTree = new DropDownTree({
    fields: { dataSource: data, text: 'name', value: 'id', parentValue: 'pid', hasChildren: 'hasChild' },
    itemTemplate: '#itemTemplate',
    width: '100%',
    cssClass: 'custom',
    valueTemplate: '#valueTemplate',
    placeholder: 'Select an employee',
    popupHeight: '250px'
});
ddtreeObj.appendTo('#template');
<!DOCTYPE html>
<html lang="en">

<head>
    <title>Essential JS 2 DropDownTree</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/ej2/29.1.33/ej2-base/styles/material.css" rel="stylesheet" />
    <link href="https://cdn.syncfusion.com/ej2/29.1.33/ej2-inputs/styles/material.css" rel="stylesheet" />
    <link href="https://cdn.syncfusion.com/ej2/29.1.33/ej2-buttons/styles/material.css" rel="stylesheet" />
    <link href="https://cdn.syncfusion.com/ej2/29.1.33/ej2-lists/styles/material.css" rel="stylesheet" />
    <link href="https://cdn.syncfusion.com/ej2/29.1.33/ej2-navigations/styles/material.css" rel="stylesheet" />
    <link href="https://cdn.syncfusion.com/ej2/29.1.33/ej2-dropdowns/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 class="stackblitz-container bootstrap5">
        <div class="col-lg-12 control-section">
            <div style="margin: 0 auto; max-width:350px;">
                <input type="text" id="template">
            </div>
        </div>
        <script id="itemTemplate" type="text/x-template">
            <div>     
                <span class="ename">${name} - </span>
                <span class="ejob">${job}</span> 
            </div>
        </script>
        <script id="valueTemplate" type="text/x-template">
            <div>     
                <span class="ename">${name} - </span>
                <span class="ejob">${job}</span> 
            </div>
        </script>
        <style>
            .custom .ejob {
                opacity: .60;
            }
        </style>
    </div>
</body>

</html>

Header template

The header element is statically shown at the top of the popup list items within the Dropdown Tree control. A custom element can be placed as a header element using the headerTemplate property.

In the following sample, the header is customized using a custom element.

import { DropDownTree } from '@syncfusion/ej2-dropdowns';

let data: { [key: string]: Object }[] = [
    { "id": 1, "name": "Steven Buchanan", "job": "General Manager", "hasChild": true, "expanded": true },
    { "id": 2, "pid": 1, "name": "Laura Callahan", "job": "Product Manager", "hasChild": true },
    { "id": 3, "pid": 2, "name": "Andrew Fuller", "job": "Team Lead", "hasChild": true },
    { "id": 4, "pid": 3, "name": "Anne Dodsworth", "job": "Developer" },
    { "id": 10, "pid": 3, "name": "Lilly", "job": "Developer", "status": "online" },
    { "id": 5, "pid": 1, "name": "Nancy Davolio", "job": "Product Manager", "hasChild": true },
    { "id": 6, "pid": 5, "name": "Michael Suyama", "job": "Team Lead", "hasChild": true },
    { "id": 7, "pid": 6, "name": "Robert King", "job": "Developer " },
    { "id": 11, "pid": 6, "name": "Mary", "job": "Developer " },
    { "id": 9, "pid": 1, "name": "Janet Leverling", "job": "HR" }
];
let ddtreeObj: DropDownTree = new DropDownTree({
    fields: { dataSource: data, text: 'name', value: 'id', parentValue: 'pid', hasChildren: 'hasChild' },
    headerTemplate: '#headerTemplate',
    width: '100%',
    cssClass: 'custom',
    placeholder: 'Select an employee',
    popupHeight: '250px'
});
ddtreeObj.appendTo('#template');
<!DOCTYPE html>
<html lang="en">

<head>
    <title>Essential JS 2 Dropdown Tree</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/ej2/29.1.33/ej2-base/styles/material.css" rel="stylesheet" />
    <link href="https://cdn.syncfusion.com/ej2/29.1.33/ej2-inputs/styles/material.css" rel="stylesheet" />
    <link href="https://cdn.syncfusion.com/ej2/29.1.33/ej2-buttons/styles/material.css" rel="stylesheet" />
    <link href="https://cdn.syncfusion.com/ej2/29.1.33/ej2-lists/styles/material.css" rel="stylesheet" />
    <link href="https://cdn.syncfusion.com/ej2/29.1.33/ej2-navigations/styles/material.css" rel="stylesheet" />
    <link href="https://cdn.syncfusion.com/ej2/29.1.33/ej2-dropdowns/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 class="stackblitz-container bootstrap5">
        <div class="col-lg-12 control-section">
            <div style="margin: 0 auto; max-width:350px;">
                <input type="text" id="template">
            </div>
        </div>
        <script id="headerTemplate" type="text/x-template">
            <div class="head"> Employee List </div>
        </script>
    </div>
    <style>
        .custom .head {
            height: 40px;
            line-height: 40px;
            font-size: 14px;
            margin: 0 auto;
            width: 100%;
            padding: 0 20px;
            font-weight: bold;
            border-bottom: 1px solid #e0e0e0;
        }
    </style>
</body>
</html>

The Dropdown Tree control has options to display a footer element at the bottom of the list items in the popup list. A custom element can be placed as a footer element using the footerTemplate property.

In the following sample, the footer element displays the total number of employees present in the Dropdown Tree control.

import { DropDownTree } from '@syncfusion/ej2-dropdowns';

let data: { [key: string]: Object }[] = [
    { "id": 1, "name": "Steven Buchanan", "job": "General Manager", "hasChild": true, "expanded": true },
    { "id": 2, "pid": 1, "name": "Laura Callahan", "job": "Product Manager", "hasChild": true },
    { "id": 3, "pid": 2, "name": "Andrew Fuller", "job": "Team Lead", "hasChild": true },
    { "id": 4, "pid": 3, "name": "Anne Dodsworth", "job": "Developer" },
    { "id": 10, "pid": 3, "name": "Lilly", "job": "Developer", "status": "online" },
    { "id": 5, "pid": 1, "name": "Nancy Davolio", "job": "Product Manager", "hasChild": true },
    { "id": 6, "pid": 5, "name": "Michael Suyama", "job": "Team Lead", "hasChild": true },
    { "id": 7, "pid": 6, "name": "Robert King", "job": "Developer " },
    { "id": 11, "pid": 6, "name": "Mary", "job": "Developer " },
    { "id": 9, "pid": 1, "name": "Janet Leverling", "job": "HR" }
];
let ddtreeObj: DropDownTree = new DropDownTree({
    fields: { dataSource: data, text: 'name', value: 'id', parentValue: 'pid', hasChildren: 'hasChild' },
    footerTemplate: "<span class='foot'> Total number of employees: " + data.length + "</span>",
    width: '100%',
    cssClass: 'custom',
    placeholder: 'Select an employee',
    popupHeight: '250px'
});
ddtreeObj.appendTo('#template');
<!DOCTYPE html>
<html lang="en">
<head>
    <title>Essential JS 2 Dropdown Tree</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/ej2/29.1.33/ej2-base/styles/material.css" rel="stylesheet" />
    <link href="https://cdn.syncfusion.com/ej2/29.1.33/ej2-inputs/styles/material.css" rel="stylesheet" />
    <link href="https://cdn.syncfusion.com/ej2/29.1.33/ej2-buttons/styles/material.css" rel="stylesheet" />
    <link href="https://cdn.syncfusion.com/ej2/29.1.33/ej2-lists/styles/material.css" rel="stylesheet" />
    <link href="https://cdn.syncfusion.com/ej2/29.1.33/ej2-navigations/styles/material.css" rel="stylesheet" />
    <link href="https://cdn.syncfusion.com/ej2/29.1.33/ej2-dropdowns/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 class="stackblitz-container bootstrap5">
        <div class="col-lg-12 control-section">
            <div style="margin: 0 auto; max-width:350px;">
                <input type="text" id="template">
            </div>
        </div>
    </div>
    <style>
        .custom .foot {
            height: 40px;
            line-height: 40px;
            font-size: 14px;
            margin: 0 auto;
            width: 100%;
            padding: 0 20px;
            font-weight: bold;
        }

        .custom .e-ddt-footer {
            border-top: 1px solid #e0e0e0;
        }
    </style>
</body>

</html>

No Records template

The Dropdown Tree control can display custom designs in the popup list content using the noRecordsTemplate property when no matches are found during a search and datasource is empty.

In the following sample, the popup list content displays a notification of no data available.

import { DropDownTree } from '@syncfusion/ej2-dropdowns';

let data: { [key: string]: Object }[] = [];
let ddtreeObj: DropDownTree = new DropDownTree({
    fields: { dataSource: data, text: 'name', value: 'id', parentValue: 'pid', hasChildren: 'hasChild' },
    noRecordsTemplate: "<span class='norecord'> NO DATA AVAILABLE</span>",
    width: '100%',
    placeholder: 'Select an employee',
    popupHeight: '250px'
});
ddtreeObj.appendTo('#template');
<!DOCTYPE html>
<html lang="en">

<head>
    <title>Essential JS 2 Dropdown Tree</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/ej2/29.1.33/ej2-base/styles/material.css" rel="stylesheet" />
    <link href="https://cdn.syncfusion.com/ej2/29.1.33/ej2-inputs/styles/material.css" rel="stylesheet" />
    <link href="https://cdn.syncfusion.com/ej2/29.1.33/ej2-buttons/styles/material.css" rel="stylesheet" />
    <link href="https://cdn.syncfusion.com/ej2/29.1.33/ej2-lists/styles/material.css" rel="stylesheet" />
    <link href="https://cdn.syncfusion.com/ej2/29.1.33/ej2-navigations/styles/material.css" rel="stylesheet" />
    <link href="https://cdn.syncfusion.com/ej2/29.1.33/ej2-dropdowns/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 class="stackblitz-container bootstrap5">
        <div class="col-lg-12 control-section">
            <div style="margin: 0 auto; max-width:350px;">
                <input type="text" id="template">
            </div>
        </div>
    </div>
</body>
</html>

Action failure template

The Dropdown Tree control provides an option to custom design the popup list content using the actionFailureTemplate property when the data fetch request fails at the remote server.

In the following sample, when the data fetch request fails, the Dropdown Tree control displays a notification.

import { DropDownTree } from '@syncfusion/ej2-dropdowns';
import { Query, DataManager, ODataV4Adaptor } from '@syncfusion/ej2-data';

let data: DataManager = new DataManager({
    url: 'https://services.odata.org/V4/Northwind/Northwind.svs',
    adaptor: new ODataV4Adaptor,
    crossDomain: true,
});
let query: Query = new Query().from('Employees').select('EmployeeID,FirstName,Title').take(5);
let query1: Query = new Query().from('Orders').select('OrderID,EmployeeID,ShipName').take(5);
let ddTreeObj: DropDownTree = new DropDownTree({
    fields: {
        dataSource: data, query: query, value: 'EmployeeID', text: 'FirstName', hasChildren: 'EmployeeID',
        child: { dataSource: data, query: query1, value: 'OrderID', parentValue: 'EmployeeID', text: 'ShipName' }
    },
    width: '100%',
    actionFailureTemplate: "<span class='action-failure'> Data fetch request fails</span>",
    placeholder: 'Select an employee',
    popupHeight: '250px'
});
ddTreeObj.appendTo('#template');
<!DOCTYPE html>
<html lang="en">

<head>
    <title>Essential JS 2 Dropdown Tree</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/ej2/29.1.33/ej2-base/styles/material.css" rel="stylesheet" />
    <link href="https://cdn.syncfusion.com/ej2/29.1.33/ej2-inputs/styles/material.css" rel="stylesheet" />
    <link href="https://cdn.syncfusion.com/ej2/29.1.33/ej2-buttons/styles/material.css" rel="stylesheet" />
    <link href="https://cdn.syncfusion.com/ej2/29.1.33/ej2-lists/styles/material.css" rel="stylesheet" />
    <link href="https://cdn.syncfusion.com/ej2/29.1.33/ej2-navigations/styles/material.css" rel="stylesheet" />
    <link href="https://cdn.syncfusion.com/ej2/29.1.33/ej2-dropdowns/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 class="stackblitz-container bootstrap5">
        <div class="col-lg-12 control-section">
            <div style="margin: 0 auto; max-width:350px;">
                <input type="text" id="template">
            </div>
        </div>
    </div>
</body>
</html>

Custom template to show selected items in input

In the Dropdown Tree control, while selecting more than one item via checkbox or multi-selection support, all the selected items will be displayed in the input. Instead of displaying all the selected item text, a custom template can be displayed by setting the mode property as Custom and using the customTemplate property.

When the mode property is set as Custom, the Dropdown Tree control displays the default template value (${value.length} item(s) selected) like 1 item(s) selected or 2 item(s) selected. The default template can be customized using the customTemplate property.

In the following sample, the Dropdown Tree control is rendered with the default value of the customTemplate property like “1 item(s) selected or 2 item(s) selected”.

import { DropDownTree } from '@syncfusion/ej2-dropdowns';

let data: { [key: string]: Object }[] = [
    { "id": 1, "name": "Steven Buchanan", "job": "General Manager", "hasChild": true, "expanded": true },
    { "id": 2, "pid": 1, "name": "Laura Callahan", "job": "Product Manager", "hasChild": true },
    { "id": 3, "pid": 2, "name": "Andrew Fuller", "job": "Team Lead", "hasChild": true },
    { "id": 4, "pid": 3, "name": "Anne Dodsworth", "job": "Developer" },
    { "id": 10, "pid": 3, "name": "Lilly", "job": "Developer", "status": "online" },
    { "id": 5, "pid": 1, "name": "Nancy Davolio", "job": "Product Manager", "hasChild": true },
    { "id": 6, "pid": 5, "name": "Michael Suyama", "job": "Team Lead", "hasChild": true },
    { "id": 7, "pid": 6, "name": "Robert King", "job": "Developer " },
    { "id": 11, "pid": 6, "name": "Mary", "job": "Developer " },
    { "id": 9, "pid": 1, "name": "Janet Leverling", "job": "HR" }
];
let checkList: DropDownTree = new DropDownTree({
    fields: { dataSource: data, text: 'name', value: 'id', parentValue: 'pid', hasChildren: 'hasChild' },
    placeholder: 'Select items',
    popupHeight: '200px',
    mode: 'Custom',
    showCheckBox: true,
    treeSettings: { autoCheck: true }
});
checkList.appendTo('#checkbox');
<!DOCTYPE html>
<html lang="en">

<head>
    <title>Essential JS 2 Dropdown Tree</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/ej2/29.1.33/ej2-base/styles/material.css" rel="stylesheet" />
    <link href="https://cdn.syncfusion.com/ej2/29.1.33/ej2-inputs/styles/material.css" rel="stylesheet" />
    <link href="https://cdn.syncfusion.com/ej2/29.1.33/ej2-buttons/styles/material.css" rel="stylesheet" />
    <link href="https://cdn.syncfusion.com/ej2/29.1.33/ej2-lists/styles/material.css" rel="stylesheet" />
    <link href="https://cdn.syncfusion.com/ej2/29.1.33/ej2-navigations/styles/material.css" rel="stylesheet" />
    <link href="https://cdn.syncfusion.com/ej2/29.1.33/ej2-dropdowns/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 class="stackblitz-container bootstrap5">
        <div class="col-lg-12 control-section">
            <div style="margin: 0 auto; max-width:350px;">
                <input type="text" id="checkbox">
            </div>
        </div>
    </div>       
</body>
</html>

In the following sample, the Dropdown Tree control is rendered with a custom value of the customTemplate property like Selected items count: 2.

import { DropDownTree } from '@syncfusion/ej2-dropdowns';

let data: { [key: string]: Object }[] = [
    { "id": 1, "name": "Steven Buchanan", "job": "General Manager", "hasChild": true, "expanded": true },
    { "id": 2, "pid": 1, "name": "Laura Callahan", "job": "Product Manager", "hasChild": true },
    { "id": 3, "pid": 2, "name": "Andrew Fuller", "job": "Team Lead", "hasChild": true },
    { "id": 4, "pid": 3, "name": "Anne Dodsworth", "job": "Developer" },
    { "id": 10, "pid": 3, "name": "Lilly", "job": "Developer", "status": "online" },
    { "id": 5, "pid": 1, "name": "Nancy Davolio", "job": "Product Manager", "hasChild": true },
    { "id": 6, "pid": 5, "name": "Michael Suyama", "job": "Team Lead", "hasChild": true },
    { "id": 7, "pid": 6, "name": "Robert King", "job": "Developer " },
    { "id": 11, "pid": 6, "name": "Mary", "job": "Developer " },
    { "id": 9, "pid": 1, "name": "Janet Leverling", "job": "HR" }
];
let checkList: DropDownTree = new DropDownTree({
    fields: { dataSource: data, text: 'name', value: 'id', parentValue: 'pid', hasChildren: 'hasChild' },
    placeholder: 'Select items',
    popupHeight: '200px',
    mode: 'Custom',
    customTemplate: "Selected items count: ${value.length}",
    showCheckBox: true,
    treeSettings: { autoCheck: true }
});
checkList.appendTo('#checkbox');
<!DOCTYPE html>
<html lang="en">

<head>
    <title>Essential JS 2 Dropdown Tree</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/ej2/29.1.33/ej2-base/styles/material.css" rel="stylesheet" />
    <link href="https://cdn.syncfusion.com/ej2/29.1.33/ej2-inputs/styles/material.css" rel="stylesheet" />
    <link href="https://cdn.syncfusion.com/ej2/29.1.33/ej2-buttons/styles/material.css" rel="stylesheet" />
    <link href="https://cdn.syncfusion.com/ej2/29.1.33/ej2-lists/styles/material.css" rel="stylesheet" />
    <link href="https://cdn.syncfusion.com/ej2/29.1.33/ej2-navigations/styles/material.css" rel="stylesheet" />
    <link href="https://cdn.syncfusion.com/ej2/29.1.33/ej2-dropdowns/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 class="stackblitz-container bootstrap5">
        <div class="col-lg-12 control-section">
            <div style="margin: 0 auto; max-width:350px;">
                <input type="text" id="checkbox">
            </div>
        </div>
    </div>   
</body>
</html>