Process the tree node operations using context menu in Angular Treeview component
27 Apr 202417 minutes to read
You can intergrade the context menu with ‘TreeView’ component in order to perform the tree view related operations like add, remove and renaming node.
Following is an example which demonstrates the above cases which are used to manipulate tree view operations in the ‘select ‘ event of context menu.
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 { bootstrapApplication } from '@angular/platform-browser';
import { AppComponent } from './app.component';
import 'zone.js';
bootstrapApplication(AppComponent).catch((err) => console.error(err));