Angular PrimeNG Basic Tree

Last Updated : 29 Aug, 2022

Angular PrimeNG is an open-source framework with a rich set of native Angular UI components that are used for great styling and this framework is used to make responsive websites with very much ease. This article will show us how to use the Basic TreeTable in Angular PrimeNG.

Angular PrimeNG Basic Tree is used to display hierarchical data. we can easily modify, manipulate, and show the data in a hierarchical way using Basic TreeTable Component.

Syntax:

<p-tree [value]="..."></p-tree>

Creating Angular application & Module Installation:

Step 1: Create an Angular application using the following command.

ng new appname

Step 2: After creating your project folder i.e. appname, move to it using the following command.

cd appname

Step 3: Install PrimeNG in your given directory.

npm install primeng --save
npm install primeicons --save

Project Structure: It will look like the following:

Project Structure

Example 1: Below is a simple example that demonstrates the use of the Angular PrimeNG Tree, In this example, we are making a simple and basic Tree Component.

app.component.html

<h2 style="color: green">GeeksforGeeks</h2> 
<h4>Angular PrimeNG Basic Tree</h4> 
<p-tree [value]="files1"></p-tree>

app.component.ts

import { Component, OnInit } from '@angular/core'; 
import { NodeService } from './nodeservice'; 
import { TreeNode } from 'primeng/api'; 
  
@Component({ 
    selector: 'app-root', 
    templateUrl: './app.component.html', 
}) 
export class AppComponent { 
    files1: TreeNode[] = []; 
  
    constructor(private nodeService: NodeService) { } 
  
    ngOnInit() { 
        this.files1 = [ 
            { 
                label: 'A', 
                children: [ 
                    { 
                        label: 'B', 
  
                        children: [ 
                            { 
                                label: 'C', 
                            }, 
                            { 
                                label: 'D', 
                            }, 
                        ], 
                    }, 
                    { 
                        label: 'E', 
  
                        children: [ 
                            { 
                                label: 'F', 
                            }, 
                        ], 
                    }, 
                ], 
            }, 
            { 
                label: 'G', 
  
                children: [ 
                    { 
                        label: 'H', 
                    }, 
                    { 
                        label: 'I', 
                    }, 
                    { 
                        label: 'J', 
                    }, 
                ], 
            }, 
        ]; 
    } 
} 

app.module.ts

import { NgModule } from '@angular/core'; 
import { BrowserModule } from '@angular/platform-browser'; 
import { FormsModule } from '@angular/forms'; 
import { HttpClientModule } from '@angular/common/http'; 
import { BrowserAnimationsModule }  
    from '@angular/platform-browser/animations'; 
import { AppComponent } from './app.component'; 
import { NodeService } from './nodeservice'; 
import { TreeModule } from 'primeng/tree'; 
import { ButtonModule } from 'primeng/button'; 
import { InputTextModule } from 'primeng/inputtext'; 
  
@NgModule({ 
    imports: [ 
        BrowserModule, 
        BrowserAnimationsModule, 
        TreeModule, 
        ButtonModule, 
        InputTextModule, 
        HttpClientModule, 
        FormsModule, 
    ], 
    declarations: [AppComponent], 
    bootstrap: [AppComponent], 
    providers: [NodeService], 
}) 
export class AppModule { } 

Run the below command to start the app.

ng serve --open

Output:

Example 2: Below is a simple example that demonstrates the use of the Angular PrimeNG Tree, In this example, we are making a simple and basic Tree Component with icons along with the text.

app.component.html

<h2 style="color: green">GeeksforGeeks</h2> 
<h4>Angular PrimeNG Basic Tree</h4> 
<p-tree [value]="files1"></p-tree>

app.component.ts

import { Component, OnInit } from '@angular/core'; 
import { NodeService } from './nodeservice'; 
import { TreeNode } from 'primeng/api'; 
  
@Component({ 
    selector: 'app-root', 
    templateUrl: './app.component.html', 
}) 
export class AppComponent { 
    files1: TreeNode[] = []; 
  
    constructor(private nodeService: NodeService) { } 
  
    ngOnInit() { 
        this.files1 = [ 
            { 
                label: 'A', 
                expandedIcon: 'pi pi-folder-open', 
                collapsedIcon: 'pi pi-folder', 
                children: [ 
                    { 
                        label: 'B', 
                        expandedIcon: 'pi pi-folder-open', 
                        collapsedIcon: 'pi pi-folder', 
                        children: [ 
                            { 
                                label: 'C', 
                                icon: 'pi pi-folder', 
                            }, 
                            { 
                                label: 'D', 
                                icon: 'pi pi-folder', 
                            }, 
                        ], 
                    }, 
                    { 
                        label: 'E', 
                        expandedIcon: 'pi pi-folder-open', 
                        collapsedIcon: 'pi pi-folder', 
                        children: [ 
                            { 
                                label: 'F', 
                                icon: 'pi pi-folder', 
                            }, 
                        ], 
                    }, 
                ], 
            }, 
            { 
                label: 'G', 
                collapsedIcon: 'pi pi-folder', 
                expandedIcon: 'pi pi-folder-open', 
                children: [ 
                    { 
                        label: 'H', 
                        icon: 'pi pi-folder', 
                    }, 
                    { 
                        label: 'I', 
                        icon: 'pi pi-folder', 
                    }, 
                    { 
                        label: 'J', 
                        icon: 'pi pi-folder', 
                    }, 
                ], 
            }, 
        ]; 
    } 
} 

app.module.ts

import { NgModule } from '@angular/core'; 
import { BrowserModule } from '@angular/platform-browser'; 
import { FormsModule } from '@angular/forms'; 
import { HttpClientModule } from '@angular/common/http'; 
import { BrowserAnimationsModule }  
    from '@angular/platform-browser/animations'; 
import { AppComponent } from './app.component'; 
import { NodeService } from './nodeservice'; 
import { TreeModule } from 'primeng/tree'; 
import { ButtonModule } from 'primeng/button'; 
import { InputTextModule } from 'primeng/inputtext'; 
  
@NgModule({ 
    imports: [ 
        BrowserModule, 
        BrowserAnimationsModule, 
        TreeModule, 
        ButtonModule, 
        InputTextModule, 
        HttpClientModule, 
        FormsModule, 
    ], 
    declarations: [AppComponent], 
    bootstrap: [AppComponent], 
    providers: [NodeService], 
}) 
export class AppModule { } 