Multiple selection in React Treeview component

28 Aug 202421 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.

index.jsx

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'));

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: { [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.

index.jsx

import * as React from 'react';
import * as ReactDOM from 'react-dom';
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;
    let selectedNodes = ['2', '6'];
    function nodeSelected(e) {
        alert("The selected node's id: " + selectedNodes); // To alert the selected node's id.
    }
    return (
    // specifies the tag for render the TreeView component
    <TreeViewComponent fields={fields} allowMultiSelection={allowMultiSelection} selectedNodes={selectedNodes} nodeSelected={nodeSelected}/>);
}
export default App;
ReactDOM.render(<App />, document.getElementById('sample'));

index.tsx

import * as React from 'react';
import * as ReactDOM from 'react-dom';
import {TreeViewComponent,NodeSelectEventArgs} 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;
    let selectedNodes: string[] = ['2','6'];
    function nodeSelected(e:NodeSelectEventArgs){
        alert("The selected node's id: " + selectedNodes); // To alert the selected node's id.
    }

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

See Also

• How to hover and select the multiple line tree nodes

• How to select only one child at a time, out of one specific parent