Multiple selection in Angular TreeView component
27 Aug 202512 minutes to read
The TreeView component supports selecting multiple nodes simultaneously, enabling users to perform batch operations on several items. Selection highlights the chosen nodes and provides interactive feedback through visual indicators.
The TreeView supports multiple node selection by setting allowMultiSelection to true.
Enabling multiple selection
To select multiple nodes, use these keyboard combinations:
- Hold CTRL key and click individual nodes to add or remove them from the selection
- Hold SHIFT key and click nodes to select a continuous range from the last selected node
In the following example, the allowMultiSelection
property is enabled to demonstrate multiple node selection.
import { NgModule } from '@angular/core'
import { BrowserModule } from '@angular/platform-browser'
import { FormsModule } from '@angular/forms'
import { TreeViewModule } from '@syncfusion/ej2-angular-navigations'
import { Component, ViewChild } from '@angular/core';
import { TreeViewComponent } from '@syncfusion/ej2-angular-navigations';
@Component({
imports: [
FormsModule, TreeViewModule
],
standalone: true,
selector: 'app-container',
// specifies the template string for the TreeView component
template: `<div id='treeparent'><ejs-treeview id='treeelement' [fields]='field' [allowMultiSelection]='allowMultiSelection'></ejs-treeview></div>`
})
export class AppComponent {
@ViewChild('samples')
public tree?: TreeViewComponent;
constructor() {
}
// defined the array of data
public countries: 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
public field: Object = { dataSource: this.countries, id: 'id', parentID: 'pid', text: 'name', hasChildren: 'hasChild', selected: 'isSelected' };
// set the Multi Selection option to TreeView
public allowMultiSelection: boolean = true;
}
@import 'node_modules/@syncfusion/ej2-base/styles/material.css';
@import 'node_modules/@syncfusion/ej2-inputs/styles/material.css';
@import 'node_modules/@syncfusion/ej2-buttons/styles/material.css';
@import 'node_modules/@syncfusion/ej2-angular-base/styles/material.css';
@import 'node_modules/@syncfusion/ej2-angular-navigations/styles/material.css';
@import 'node_modules/@syncfusion/ej2-angular-inputs/styles/material.css';
import { bootstrapApplication } from '@angular/platform-browser';
import { AppComponent } from './app.component';
import 'zone.js';
bootstrapApplication(AppComponent).catch((err) => console.error(err));
Multiple selection is not supported through touch interactions on mobile devices.
Managing selected nodes
Control and retrieve selected nodes using the selectedNodes property. This property accepts and returns an array of selected node IDs, allowing both initial configuration and dynamic updates.
Selection events
The TreeView provides events to handle selection changes:
- The
nodeSelecting
event triggers before a node selection changes and can prevent the selection by settingcancel
to true - The
nodeSelected
event triggers after a node selection is completed successfully
In the following example, New South Wales and Western Australia nodes are pre-selected at initialization. The selection events display alerts showing the selected node information.
import { NgModule } from '@angular/core'
import { BrowserModule } from '@angular/platform-browser'
import { FormsModule } from '@angular/forms'
import { TreeViewModule, TreeViewComponent } from '@syncfusion/ej2-angular-navigations'
import { Component, ViewChild } from '@angular/core';
import { NodeSelectEventArgs } from '@syncfusion/ej2-navigations';
@Component({
imports: [
FormsModule, TreeViewModule
],
standalone: true,
selector: 'app-container',
// specifies the template string for the TreeView component
template: `<div id='treeparent'><ejs-treeview #tree id='treeelement' [fields]='field' [allowMultiSelection]='allowMultiSelection' [selectedNodes]='selectedNodes' (nodeSelected)='nodeSelected($event)'></ejs-treeview></div>`
})
export class AppComponent {
@ViewChild('tree')
public tree?: TreeViewComponent;
constructor() {
}
// defined the array of data
public countries: 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
public field: Object = { dataSource: this.countries, id: 'id', parentID: 'pid', text: 'name', hasChildren: 'hasChild' };
// set the Multi Selection option to the TreeView
public allowMultiSelection: boolean = true;
//set the Selected nodes to the TreeView
public selectedNodes: string[] = ['2', '6'];
//Bind the nodeSelected event
public nodeSelected(e: NodeSelectEventArgs) {
alert("The selected node's id: " + this.tree?.selectedNodes); // To alert the selected node's id.
};
}
@import 'node_modules/@syncfusion/ej2-base/styles/material.css';
@import 'node_modules/@syncfusion/ej2-inputs/styles/material.css';
@import 'node_modules/@syncfusion/ej2-buttons/styles/material.css';
@import 'node_modules/@syncfusion/ej2-angular-base/styles/material.css';
@import 'node_modules/@syncfusion/ej2-angular-navigations/styles/material.css';
@import 'node_modules/@syncfusion/ej2-angular-inputs/styles/material.css';
import { bootstrapApplication } from '@angular/platform-browser';
import { AppComponent } from './app.component';
import 'zone.js';
bootstrapApplication(AppComponent).catch((err) => console.error(err));