Angular PrimeNG Table Change Detection

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. It provides a lot of templates, components, theme design, an extensive icon library, and much more. In this article, we are going to learn Angular PrimeNG Table Change Detection.

The Table is used to display data in tabular format. The Table needs to make aware of changes in its values. The Push, Pop, or other actions don’t work in this case because of performance issues. Hence we need to splice to create a new array reference using a spread operator or similar.

Syntax:

// Modify the data
// Next splice and reference the new data array
this.data = [...this.data];

Creating Angular application & Module Installation:

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

ng new geeks_angular

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

cd geeks_angular

Step 3: Install PrimeNG in your given directory.

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

Project Structure: After successful installation, the following project structure will be displayed:

Example 1: In the following example, we have modified the data using a button that pushes data in the array. Later using another button, the Table is updated.

• app.component.html:

HTML

<h1 style="color:green;
           text-align:center;">
    GeeksforGeeks
</h1>
<h3>Angular PrimeNG Table Change Detection</h3>
<h5>Basic</h5>

<p-table #dt [value]="tutorials"
             dataKey="title"
             [rowHover]="true"
             [showCurrentPageReport]="true"
             [filterDelay]="0"
             [globalFilterFields]="['title', 'category', 'rating']">
    <ng-template pTemplate="caption">
        <div class="table-header">
            List of Tutorials
            <span class="p-input-icon-left">
                <i class="pi pi-search"></i>
                <input pInputText type="text"
                       (input)=
    "dt.filterGlobal($event.target.value, 'contains')"
                        placeholder="Global Search" />
            </span>
        </div>
    </ng-template>
    <ng-template pTemplate="header">
        <tr>
            <th style="width: 3rem"></th>
            <th pSortableColumn="title">
                Title
                <p-sortIcon field="title"></p-sortIcon>
            </th>
            <th pSortableColumn="category">
                Category
                <p-sortIcon field="category"></p-sortIcon>
            </th>
            <th pSortableColumn="rating">
                Rating
                <p-sortIcon field="rating"></p-sortIcon>
            </th>
        </tr>
    </ng-template>
    <ng-template pTemplate="body" let-tutorial>
        <tr class="p-selectable-row">
            <td>
                <p-tableCheckbox [value]="tutorial"></p-tableCheckbox>
            </td>
            <td>
                <span class="p-column-title"> Title </span>
                {{ tutorial.title }}
            </td>
            <td>
                <span class="p-column-title"> Category </span>
                <span class="image-text">
                    {{ tutorial.category }}
                </span>
            </td>
            <td>
                <span class="p-column-title"> Rating </span>
                <span class="image-text">
                    {{ tutorial.rating }}
                </span>
            </td>
        </tr>
    </ng-template>
</p-table>
<p-button label="Add Data"
          (onClick)="handleClick()">
</p-button>
<p-button label="Update Table"
          (onClick)="updateView()">
</p-button>

• app.component.ts

Javascript

import { Component, OnInit, ViewChild } from '@angular/core';
import { Table } from 'primeng/table';
import { PrimeNGConfig } from 'primeng/api';
import { MessageService } from 'primeng/api';

@Component({
    selector: 'app-root',
    templateUrl: './app.component.html',
    styles: [
        `
  :host ::ng-deep .p-cell-editing {
      padding-top: 0 !important;
      padding-bottom: 0 !important;
  }
`,
    ],
})
export class AppComponent {
    tutorials: Tutorial[];
    @ViewChild('dt') table: Table;
    clonedTutorials: { [s: string]: Tutorial } = {};
    constructor(private primengConfig: PrimeNGConfig) { }

    ngOnInit() {
        this.tutorials = [
            {
                title: 'Queue',
                category: 'Data Structure',
                rating: 8,
            },
            {
                title: 'Circularly LinkedList',
                category: 'Data Structure',
                rating: 1,
            },
            {
                title: 'Doubly LinkedList',
                category: 'Data Structure',
                rating: 3,
            },
            {
                title: 'Singly LinkedList',
                category: 'Data Structure',
                rating: 5,
            },
            {
                title: 'Doubly Ended Queue',
                category: 'Data Structure',
                rating: 10,
            },
            {
                title: 'Binary Search Tree',
                category: 'Data Structure',
                rating: 2,
            },
            {
                title: 'Red Black Tree',
                category: 'Data Structure',
                rating: 9,
            },
            {
                title: 'Breadth First Search',
                category: 'Graph',
                rating: 6,
            },
            {
                title: "Floyd's Cycle",
                category: 'Algorithm',
                rating: 7,
            },
            {
                title: 'Travelling Salesman Problem',
                category: 'Algorithm',
                rating: 4,
            },
            {
                title: 'Bellman Ford',
                category: 'Graph',
                rating: 8,
            },
            {
                title: 'KMP Algorithm',
                category: 'String',
                rating: 10,
            },
        ];

        this.primengConfig.ripple = true;
    }
    handleClick() {
        this.tutorials.push({
            title: 'Djikstra Shortest Path',
            category: 'Graph',
            rating: 5,
        });
    }
    updateView() {
        this.tutorials = [...this.tutorials];
    }
}
export interface Tutorial {
    title?: string;
    category?: string;
    rating?: number;
}

• app.module.ts

Javascript

import { NgModule } from '@angular/core';
import { BrowserModule }
    from '@angular/platform-browser';
import { FormsModule } from '@angular/forms';
import { BrowserAnimationsModule }
    from '@angular/platform-browser/animations';
import { AppComponent } from './app.component';
import { MultiSelectModule } from 'primeng/multiselect';
import { ButtonModule } from 'primeng/button';
import { TableModule } from 'primeng/table';

@NgModule({
    imports: [
        BrowserModule,
        BrowserAnimationsModule,
        TableModule,
        MultiSelectModule,
        ButtonModule,
        FormsModule,
    ],
    declarations: [AppComponent],
    bootstrap: [AppComponent],
})
export class AppModule { }

Output:

Example 2: In the following example, we have modified the Table Data with new data.

• app.component.html

HTML

<h1 style="color:green;
           text-align:center;">
  GeeksforGeeks
</h1>
<h3>Angular PrimeNG Table Change Detection</h3>
<h5>Basic</h5>

<p-table #dt [value]="tutorials"
             dataKey="title"
             [rowHover]="true"
             [showCurrentPageReport]="true"
             [filterDelay]="0"
             [globalFilterFields]="['title', 'category', 'rating']">
    <ng-template pTemplate="caption">
        <div class="table-header">
            List of Tutorials
            <span class="p-input-icon-left">
                <i class="pi pi-search"></i>
                <input pInputText type="text"
                       (input)=
    "dt.filterGlobal($event.target.value, 'contains')"
                       placeholder="Global Search" />
            </span>
        </div>
    </ng-template>
    <ng-template pTemplate="header">
        <tr>
            <th style="width: 3rem"></th>
            <th pSortableColumn="title">
                Title
                <p-sortIcon field="title"></p-sortIcon>
            </th>
            <th pSortableColumn="category">
                Category
                <p-sortIcon field="category"></p-sortIcon>
            </th>
            <th pSortableColumn="rating">
                Rating
                <p-sortIcon field="rating"></p-sortIcon>
            </th>
        </tr>
    </ng-template>
    <ng-template pTemplate="body" let-tutorial>
        <tr class="p-selectable-row">
            <td>
                <p-tableCheckbox [value]="tutorial"></p-tableCheckbox>
            </td>
            <td>
                <span class="p-column-title"> Title </span>
                {{ tutorial.title }}
            </td>
            <td>
                <span class="p-column-title"> Category </span>
                <span class="image-text">
                    {{ tutorial.category }}
                </span>
            </td>
            <td>
                <span class="p-column-title"> Rating </span>
                <span class="image-text">
                    {{ tutorial.rating }}
                </span>
            </td>
        </tr>
    </ng-template>
</p-table>
<p-button label="Update Table"
          (onClick)="updateView()">
</p-button>

• app.component.ts

Javascript

import { Component, OnInit, ViewChild } from '@angular/core';
import { Table } from 'primeng/table';
import { PrimeNGConfig } from 'primeng/api';
import { MessageService } from 'primeng/api';

@Component({
    selector: 'app-root',
    templateUrl: './app.component.html',
    styles: [
        `
  :host ::ng-deep .p-cell-editing {
      padding-top: 0 !important;
      padding-bottom: 0 !important;
  }
`,
    ],
})
export class AppComponent {
    tutorials: Tutorial[];
    @ViewChild('dt') table: Table;
    clonedTutorials: { [s: string]: Tutorial } = {};
    constructor(private primengConfig: PrimeNGConfig) { }

    ngOnInit() {
        this.tutorials = [
            {
                title: 'Queue',
                category: 'Data Structure',
                rating: 8,
            },
            {
                title: 'Circularly LinkedList',
                category: 'Data Structure',
                rating: 1,
            },
            {
                title: 'Doubly LinkedList',
                category: 'Data Structure',
                rating: 3,
            },
            {
                title: 'Singly LinkedList',
                category: 'Data Structure',
                rating: 5,
            },
            {
                title: 'Doubly Ended Queue',
                category: 'Data Structure',
                rating: 10,
            },
            {
                title: 'Binary Search Tree',
                category: 'Data Structure',
                rating: 2,
            },
            {
                title: 'Red Black Tree',
                category: 'Data Structure',
                rating: 9,
            },
            {
                title: 'Breadth First Search',
                category: 'Graph',
                rating: 6,
            },
            {
                title: "Floyd's Cycle",
                category: 'Algorithm',
                rating: 7,
            },
            {
                title: 'Travelling Salesman Problem',
                category: 'Algorithm',
                rating: 4,
            },
            {
                title: 'Bellman Ford',
                category: 'Graph',
                rating: 8,
            },
            {
                title: 'KMP Algorithm',
                category: 'String',
                rating: 10,
            },
        ];

        this.primengConfig.ripple = true;
    }

    updateView() {
        this.tutorials = [
            {
                title: 'Queue',
                category: 'Data Structure',
                rating: 8,
            },
            {
                title: 'Circularly LinkedList',
                category: 'Data Structure',
                rating: 1,
            },
            {
                title: 'Doubly LinkedList',
                category: 'Data Structure',
                rating: 3,
            },
            {
                title: 'Singly LinkedList',
                category: 'Data Structure',
                rating: 5,
            },
            {
                title: 'Doubly Ended Queue',
                category: 'Data Structure',
                rating: 10,
            },
            {
                title: 'Binary Search Tree',
                category: 'Data Structure',
                rating: 2,
            },
            {
                title: 'Red Black Tree',
                category: 'Data Structure',
                rating: 9,
            },
            {
                title: 'Breadth First Search',
                category: 'Graph',
                rating: 6,
            },
            {
                title: "Floyd's Cycle",
                category: 'Algorithm',
                rating: 7,
            },
            {
                title: 'Travelling Salesman Problem',
                category: 'Algorithm',
                rating: 4,
            },
            {
                title: 'Bellman Ford',
                category: 'Graph',
                rating: 8,
            },
            {
                title: 'KMP Algorithm',
                category: 'String',
                rating: 10,
            },
            {
                title: 'Djikstra Shortest Path',
                category: 'Graph',
                rating: 5,
            },
        ];
    }
}
export interface Tutorial {
    title?: string;
    category?: string;
    rating?: number;
}

• app.module.ts

Javascript

import { NgModule } from '@angular/core';
import { BrowserModule }
    from '@angular/platform-browser';
import { FormsModule } from '@angular/forms';
import { BrowserAnimationsModule }
    from '@angular/platform-browser/animations';
import { AppComponent } from './app.component';
import { MultiSelectModule } from 'primeng/multiselect';
import { ButtonModule } from 'primeng/button';
import { TableModule } from 'primeng/table';

@NgModule({
    imports: [
        BrowserModule,
        BrowserAnimationsModule,
        TableModule,
        MultiSelectModule,
        ButtonModule,
        FormsModule,
    ],
    declarations: [AppComponent],
    bootstrap: [AppComponent],
})
export class AppModule { }

Output:

Reference: https://primefaces.org/primeng/table