Node Editing in Angular TreeView component

03 Mar 2021 / 4 minutes to read

The TreeView allows you to edit nodes by setting the allowEditing property to true. To directly edit the nodes in place, double click the TreeView node or select the node and press F2 key.

When editing is completed by focus out or by pressing the Enter key, the modified node’s text saves automatically. If you do not want to save the modified node’s text in TreeView node, press Escape key. It does not save the edited text to the TreeView node.

Node editing can also be performed programmatically by using the beginEdit method. On passing the node ID or element through this method, the edit textbox will be created for the particular node thus allowing us to edit it.
If you need to validate or prevent editing, the nodeEditing event can be used which is triggered before the TreeView node is renamed. On successfully renaming a node the nodeEdited event will be triggered.

In the following example, the first level node’s text cannot be changed, but all other level nodes’ text can be changed.

Source

Preview

app.component.ts

app.module.ts

main.ts

import { Component } from '@angular/core';

@Component({
selector: 'app-container',
// specifies the template string for the TreeView component
template: `<div id='treeparent'><ejs-treeview id='treeelement' [fields]='field' [allowEditing]='allowEditing' (nodeEditing)='editing($event)'></ejs-treeview></div>`
})
export class AppComponent {
@ViewChild('samples')
constructor() {
}
// defined the array of data
public hierarchicalData: Object[] = [
            { id: '01', name: 'Local Disk(C:)', expanded: true,
            subChild: [
                {
                    id: '01-01', name: 'Program Files',
                    subChild: [
                        { id: '01-01-01', name: '7-Zip' },
                        { id: '01-01-02', name: 'Git' },
                        { id: '01-01-03', name: 'IIS Express' },
                    ]
                },
                {
                    id: '01-02', name: 'Users', expanded: true,
                    subChild: [
                        { id: '01-02-01', name: 'Smith' },
                        { id: '01-02-02', name: 'Public' },
                        { id: '01-02-03', name: 'Admin' },
                    ]
                },
                {
                    id: '01-03', name: 'Windows',
                    subChild: [
                        { id: '01-03-01', name: 'Boot' },
                        { id: '01-03-02', name: 'FileManager' },
                        { id: '01-03-03', name: 'System32' },
                    ]
                },
            ]
        },
        {
            id: '02', name: 'Local Disk(D:)',
            subChild: [
                {
                    id: '02-01', name: 'Personals',
                    subChild: [
                        { id: '02-01-01', name: 'My photo.png' },
                        { id: '02-01-02', name: 'Rental document.docx' },
                        { id: '02-01-03', name: 'Pay slip.pdf' },
                    ]
                },
                {
                    id: '02-02', name: 'Projects',
                    subChild: [
                        { id: '02-02-01', name: 'ASP Application' },
                        { id: '02-02-02', name: 'TypeScript Application' },
                        { id: '02-02-03', name: 'React Application' },
                    ]
                },
                {
                    id: '02-03', name: 'Office',
                    subChild: [
                        { id: '02-03-01', name: 'Work details.docx' },
                        { id: '02-03-02', name: 'Weekly report.docx' },
                        { id: '02-03-03', name: 'Wish list.csv' },
                    ]
                },
            ]
        },
        {
            id: '03', name: 'Local Disk(E:)', icon: 'folder',
            subChild: [
                {
                    id: '03-01', name: 'Pictures',
                    subChild: [
                        { id: '03-01-01', name: 'Wind.jpg' },
                        { id: '03-01-02', name: 'Stone.jpg' },
                        { id: '03-01-03', name: 'Home.jpg' },
                    ]
                },
                {
                    id: '03-02', name: 'Documents',
                        subChild: [
                        { id: '03-02-01', name: 'Environment Pollution.docx' },
                        { id: '03-02-02', name: 'Global Warming.ppt' },
                        { id: '03-02-03', name: 'Social Network.pdf' },
                    ]
                },
                {
                    id: '03-03', name: 'Study Materials',
                    subChild: [
                        { id: '03-03-01', name: 'UI-Guide.pdf' },
                        { id: '03-03-02', name: 'Tutorials.zip' },
                        { id: '03-03-03', name: 'TypeScript.7z' },
                    ]
                },
            ]
        }
];
// maps the appropriate column to fields property
public field: Object = { dataSource: this.hierarchicalData, id: 'id', text: 'name', child: 'subChild' };
// enable the editing options to the TreeView
public allowEditing: boolean = true;
//Bind the nodeChecked event
public editing(args: NodeCheckEventArgs) {
        //check whether node is root node or not
        if (args.node.parentNode.parentNode.nodeName !== "LI") {
            args.cancel = true;
        }
};
}

import { NgModule } from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';
import { FormsModule } from '@angular/forms';
import { AppComponent } from './app.component';
import { TreeViewModule } from '@syncfusion/ej2-angular-navigations';
/**
 * Module
 */
@NgModule({
    imports: [
        BrowserModule,FormsModule,TreeViewModule
    ],
    declarations: [AppComponent],
    bootstrap: [AppComponent]
})
export class AppModule { }

import { platformBrowserDynamic } from '@angular/platform-browser-dynamic';
import { enableProdMode } from '@angular/core';
import { AppModule } from './app.module';

enableProdMode();
platformBrowserDynamic().bootstrapModule(AppModule);

Node Editing in Angular TreeView component

See Also