Process the tree node operations using context menu in Angular TreeView component

7 Jan 202517 minutes to read

You can integrate the context menu with ‘TreeView’ component in order to perform the TreeView related operations like adding, removing, and renaming node.
The following example demonstrates how to use the ‘select’ event of the context menu to manipulate tree-view operations for the above-mentioned cases.

import { NgModule } from '@angular/core'
import { BrowserModule } from '@angular/platform-browser'
import { FormsModule } from '@angular/forms'
import { TreeViewModule, ContextMenuModule } from '@syncfusion/ej2-angular-navigations';
import { NodeClickEventArgs, BeforeOpenCloseMenuEventArgs, MenuEventArgs, MenuItemModel } from '@syncfusion/ej2-navigations';
import { Component, Inject, ViewChild } from '@angular/core';
import { TreeViewComponent, ContextMenuComponent } from '@syncfusion/ej2-angular-navigations';

@Component({
imports: [
        FormsModule, TreeViewModule, ContextMenuModule
    ],


standalone: true,
    selector: 'app-container',
    template: `<div id='treeparent'>
                 <ejs-treeview  id='tree' #treevalidate [fields]='field' (nodeClicked)='nodeclicked($event)'></ejs-treeview>
                 </div>
                 <ejs-contextmenu #contentmenutree id='contentmenutree' target='#tree' [items]='menuItems' (beforeOpen)='beforeopen($event)' (select)='menuclick($event)'></ejs-contextmenu>`
})
export class AppComponent {

  public hierarchicalData: Object[] = [
        { id: '01', name: 'Local Disk (C:)', expanded: true, hasAttribute:{class:'remove rename'},
            subChild: [
                {
                    id: '01-01', name: 'Program Files',
                    subChild: [
                        { id: '01-01-01', name: 'Windows NT' },
                        { id: '01-01-02', name: 'Windows Mail' },
                        { id: '01-01-03', name: 'Windows Photo Viewer' },
                    ]
                },
                {
                    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:)', hasAttribute:{class:'remove'},
            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', hasAttribute:{class:'rename'},
            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' },
                    ]
                },
            ]
        }
    ];
    // Mapping TreeView fields property with data source properties
    public field:Object ={ dataSource: this.hierarchicalData, id: 'id', text: 'name', child: 'subChild', htmlAttributes: 'hasAttribute' };

    @ViewChild ('treevalidate') treevalidate?: TreeViewComponent;
    @ViewChild ('contentmenutree') contentmenutree?: ContextMenuComponent;

    public nodeclicked(args: NodeClickEventArgs) {
        if (args.event.which === 3) {
            (this.treevalidate as TreeViewComponent).selectedNodes = [args.node.getAttribute('data-uid') as string];
        }
    }

 //Render the context menu with target as Treeview
public menuItems: MenuItemModel[] = [
    { text: 'Add New Item' },
    { text: 'Rename Item' },
    { text: 'Remove Item' }
];

public index: number = 1;
public menuclick(args: MenuEventArgs) {
    let targetNodeId: string = this.treevalidate?.selectedNodes[0] as string;
    if (args.item.text == "Add New Item") {
    let nodeId: string = "tree_" + this.index;
    let item: { [key: string]: Object } = { id: nodeId, name: "New Folder" };
        this.treevalidate?.addNodes([item], targetNodeId, null as any);
        this.index++;
        this.hierarchicalData.push(item);
        this.treevalidate?.beginEdit(nodeId);
    }
    else if (args.item.text == "Remove Item") {
        this.treevalidate?.removeNodes([targetNodeId]);
    }
    else if (args.item.text == "Rename Item") {
        this.treevalidate?.beginEdit(targetNodeId);
    }
}

public beforeopen(args: BeforeOpenCloseMenuEventArgs) {
    let targetNodeId: string = this.treevalidate?.selectedNodes[0] as string;
    let targetNode: Element = document.querySelector('[data-uid="' + targetNodeId + '"]') as Element;
    if (targetNode.classList.contains('remove')) {
        this.contentmenutree?.enableItems(['Remove Item'], false);
    }
    else {
        this.contentmenutree?.enableItems(['Remove Item'], true);
    }
    if (targetNode.classList.contains('rename')) {
        this.contentmenutree?.enableItems(['Rename Item'], false);
    }
    else {
        this.contentmenutree?.enableItems(['Rename Item'], 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 { bootstrapApplication } from '@angular/platform-browser';
import { AppComponent } from './app.component';
import 'zone.js';
bootstrapApplication(AppComponent).catch((err) => console.error(err));