Customize the tree nodes based on levels in Angular Treeview component

6 Sep 202214 minutes to read

You can customize the tree nodes level wise by adding custom cssClass to the component and enabling styles.

app.component.ts

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

@Component({
    selector: 'app-container',
    template:  `<div id='treeparent'><ejs-treeview id='treeElement' #treevalidate [fields]='field' [cssClass]='cssClass'></ejs-treeview></div>
                <div class="details">
                    <label>Note:</label>
                       <div><b>1. The font-weight "Bold" is applied for all the leaf nodes</b></div>
                       <div><i>2. The font-weight "Italic" is applied for first level nodes</i></div>
                       <div style="color: darkmagenta">3. The color "darkmagenta" is applied for second level nodes</div>
                    </div>`
})
export class AppComponent {
      // Hierarchical data source for TreeView component
   public hierarchicalData: Object[] = [
        { id: '01', name: 'Local Disk (C:)', expanded: true,
            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:)',
            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' },
                    ]
                },
            ]
        }
    ];
    // Mapping TreeView fields property with data source properties
    public field:Object ={ dataSource: this.hierarchicalData, id: 'id', text: 'name', child: 'subChild' };
    public cssClass: string = 'mytree';
}

app.module.ts

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 { }

main.ts

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

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