Multi Selection in React TreeView component

25 Jan 2023 / 5 minutes to read

Selection provides an interactive support and highlights the node that you select. Selection can be done through simple mouse down or keyboard interaction.

The TreeView also supports selection of multiple nodes by setting allowMultiSelection to true.

To multi-select, press and hold CTRL key and click the desired nodes. To select range of nodes, press and hold the SHIFT key and click the nodes.

In the following example, the allowMultiSelection property is enabled.

Multi selection is not applicable through touch interactions.

Source

Preview

index.jsx

index.html

index.tsx

import * as React from 'react';
import * as ReactDOM from 'react-dom';
import { enableRipple } from '@syncfusion/ej2-base';
enableRipple(true);
import { TreeViewComponent } from '@syncfusion/ej2-react-navigations';
function App() {
    // define the JSON of data
    let countries = [
        { id: 1, name: 'Australia', hasChild: true, expanded: true },
        { id: 2, pid: 1, name: 'New South Wales', isSelected: true },
        { id: 3, pid: 1, name: 'Victoria' },
        { id: 4, pid: 1, name: 'South Australia' },
        { id: 6, pid: 1, name: 'Western Australia', isSelected: true },
        { id: 7, name: 'Brazil', hasChild: true },
        { id: 8, pid: 7, name: 'Paraná' },
        { id: 9, pid: 7, name: 'Ceará' },
        { id: 10, pid: 7, name: 'Acre' },
        { id: 11, name: 'China', hasChild: true },
        { id: 12, pid: 11, name: 'Guangzhou' },
        { id: 13, pid: 11, name: 'Shanghai' },
        { id: 14, pid: 11, name: 'Beijing' },
        { id: 15, pid: 11, name: 'Shantou' },
        { id: 16, name: 'France', hasChild: true },
        { id: 17, pid: 16, name: 'Pays de la Loire' },
        { id: 18, pid: 16, name: 'Aquitaine' },
        { id: 19, pid: 16, name: 'Brittany' },
        { id: 20, pid: 16, name: 'Lorraine' },
        { id: 21, name: 'India', hasChild: true },
        { id: 22, pid: 21, name: 'Assam' },
        { id: 23, pid: 21, name: 'Bihar' },
        { id: 24, pid: 21, name: 'Tamil Nadu' },
        { id: 25, pid: 21, name: 'Punjab' }
    ];
    // maps the appropriate column to fields property
    let fields = { dataSource: countries, id: 'id', parentID: 'pid', text: 'name', hasChildren: 'hasChild', selected: 'isSelected' };
    // set the Multi Selection option to TreeView
    let allowMultiSelection = true;
    return (
    // specifies the tag for render the TreeView component
    <TreeViewComponent fields={fields} allowMultiSelection={allowMultiSelection}/>);
}
export default App;
ReactDOM.render(<App />, document.getElementById('sample'));

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

<head>
            
    <title>Syncfusion React 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 React Components" />
    <meta name="author" content="Syncfusion" />
    <link href="style.css" rel="stylesheet"/>
    <link href="//cdn.syncfusion.com/ej2/20.4.38/ej2-base/styles/material.css" rel="stylesheet" />
    <link href="//cdn.syncfusion.com/ej2/20.4.38/ej2-inputs/styles/material.css" rel="stylesheet" />
    <link href="//cdn.syncfusion.com/ej2/20.4.38/ej2-buttons/styles/material.css" rel="stylesheet" />
    <link href="//cdn.syncfusion.com/ej2/20.4.38/ej2-react-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>
</head>

<body>
    <div id='treeparent'>
        <div id='sample'>
            <div id='loader'>Loading....</div>
        </div>
    </div>
</body>

</html>

import * as React from 'react';
import * as ReactDOM from 'react-dom';
import {enableRipple} from '@syncfusion/ej2-base';
enableRipple(true);
import {TreeViewComponent} from '@syncfusion/ej2-react-navigations';

function App() {

    // define the JSON of data
  let countries: { [key: string]: Object }[] = [
            { id: 1, name: 'Australia', hasChild: true, expanded: true },
            { id: 2, pid: 1, name: 'New South Wales', isSelected: true },
            { id: 3, pid: 1, name: 'Victoria' },
            { id: 4, pid: 1, name: 'South Australia' },
            { id: 6, pid: 1, name: 'Western Australia', isSelected: true },
            { id: 7, name: 'Brazil', hasChild: true },
            { id: 8, pid: 7, name: 'Paraná' },
            { id: 9, pid: 7, name: 'Ceará' },
            { id: 10, pid: 7, name: 'Acre' },
            { id: 11, name: 'China', hasChild: true },
            { id: 12, pid: 11, name: 'Guangzhou' },
            { id: 13, pid: 11, name: 'Shanghai' },
            { id: 14, pid: 11, name: 'Beijing' },
            { id: 15, pid: 11, name: 'Shantou' },
            { id: 16, name: 'France', hasChild: true },
            { id: 17, pid: 16, name: 'Pays de la Loire' },
            { id: 18, pid: 16, name: 'Aquitaine' },
            { id: 19, pid: 16, name: 'Brittany' },
            { id: 20, pid: 16, name: 'Lorraine' },
            { id: 21, name: 'India', hasChild: true },
            { id: 22, pid: 21, name: 'Assam' },
            { id: 23, pid: 21, name: 'Bihar' },
            { id: 24, pid: 21, name: 'Tamil Nadu' },
            { id: 25, pid: 21, name: 'Punjab' }
    ];
    // maps the appropriate column to fields property
    let fields: Object = { dataSource: countries, id: 'id', parentID: 'pid', text: 'name', hasChildren: 'hasChild', selected: 'isSelected' };
    // set the Multi Selection option to TreeView
    let allowMultiSelection: boolean = true;

    return (
        // specifies the tag for render the TreeView component
        <TreeViewComponent fields={fields} allowMultiSelection={ allowMultiSelection }/>
    );
}
export default App;
ReactDOM.render(<App />, document.getElementById('sample'));

Selected nodes

You can get or set the selected nodes in TreeView at initial rendering and dynamically by using the selectedNodes property. It will return the selected node’s ID as an array.

The nodeselecting event is triggered before a node is selected/unselected which can be used to prevent the selection.
The nodeSelected event is triggered once a node is successfully selected/unselected.

In the following example, New South Wales and Western Australia nodes are selected at initial rendering. When a node is selected, the selected node’s ID is displayed in alert.