Angular MDBootstrap Collapse Component

MDBootstrap is a Material Design and bootstrap-based Angular UI library that is used to make attractive webpages with its seamless and easy-to-use component. In this article, we will know how to use Collapse Component in Angular MDBootstrap.

The Collapse Component indicates a collapsible element i.e. the content that will be shown or hidden with a click of a button.

Syntax:

<button mdbBtn (click)="gfg.toggle()" mdbWavesEffect>
   Click here
</button>
<div mdbCollapse #gfg="bs-collapse">
      <p>Content</p>
</div>

Approach:

• Download Angular MDBootstrap from the official site.
• Extract the files and change them to the working directory.
• Install npm in the current project using the following command:

npm install

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

cd appname

• Start the server using the following command:

ng serve

Project Structure: After complete installation, it will look like the following:

Project Structure

Example 1: This is the basic example that illustrates how to use the Collapse Component in Angular MDBootstrap.

app.component.html

<div id='gfg'>
    <h1>GeeksforGeeks</h1>
    <h4>Angular MDBootstrap Collapse Component</h4>
    <br />
    <div>
        <button mdbBtn color="primary"
                class="waves-light"
                type="button"
                (click)="gfg.toggle()" mdbWavesEffect>
            Click Here To Toggle!
        </button>
        <div mdbCollapse #gfg="bs-collapse">
            <p>
                MDBootstrap is a bootstrap-based angular UI
                library that is used to make good looking<br/>
                webpages with its seamless and
                easy-to-use component.
            </p>
        </div>
    </div>
</div>

app.component.ts

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

@Component({
  selector: 'my-app',
  templateUrl: './app.component.html',
  styleUrls: ['./app.component.css']
})
export class AppComponent{}

app.module.ts

import { BrowserModule } from "@angular/platform-browser";
import { NgModule } from "@angular/core";
import { BrowserAnimationsModule }
    from "@angular/platform-browser/animations";

import { AppComponent } from "./app.component";
import { MDBBootstrapModule } from "angular-bootstrap-md";
import { FormsModule } from "@angular/forms";

@NgModule({
  declarations: [AppComponent],
  imports: [
    BrowserModule,
    BrowserAnimationsModule,
    MDBBootstrapModule.forRoot(),
    FormsModule,
  ],
  providers: [],
  bootstrap: [AppComponent],
})
export class AppModule {}

Output:

Example 2: In this example, we have collapsed the text in the ngAfterViewInit lifecycle in Angular MDBootstrap.

app.component.html

<div id="gfg">
    <h1>GeeksforGeeks</h1>
    <h4>
        Angular MDBootstrap Collapse Component
    </h4>
    <br />
    <button mdbBtn color="success"
            type="button"
            (click)="test.toggle(); togglebg()" mdbWavesEffect>
        Click Here To Toggle
    </button>
    <div mdbCollapse [isCollapsed]="true"
         #test="bs-collapse">
        <p *ngIf="togglevisible">
            MDBootstrap is a bootstrap-based angular
            UI library that is used to make good looking<br />
            webpages with its seamless and easy-to-use component.
        </p>
    </div>
</div>

app.component.ts

import { AfterViewInit, Component, ViewChildren } from "@angular/core";

@Component({
  selector: "my-app",
  templateUrl: "./app.component.html",
  styleUrls: ["./app.component.css"],
})
export class AppComponent implements AfterViewInit {
  @ViewChildren(AppComponent) collapses!: AppComponent[];

  ngAfterViewInit(): void {}
  togglevisible = false;

  togglebg() {
    this.togglevisible = !this.togglevisible;
  }
}

app.module.ts

import { BrowserModule } from "@angular/platform-browser";
import { NgModule } from "@angular/core";
import { BrowserAnimationsModule }
    from "@angular/platform-browser/animations";

import { AppComponent } from "./app.component";
import { CollapseModule, MDBBootstrapModule }
    from "angular-bootstrap-md";
import { FormsModule } from "@angular/forms";

@NgModule({
  declarations: [AppComponent],
  imports: [
    BrowserModule,
    BrowserAnimationsModule,
    MDBBootstrapModule.forRoot(),
    FormsModule,
    CollapseModule,
  ],
  providers: [],
  bootstrap: [AppComponent],
})
export class AppModule {}

app.component.css

#gfg{
    margin: 40px
}
.a{
    border-radius: 5px;
    border: 2px solid black;
    padding: 10px;
}

Output:

Reference: https://mdbootstrap.com/docs/angular/advanced/collapse/