Accessibility in Angular Accordion component

30 Jan 20237 minutes to read

The Accordion component has been designed keeping in mind the WAI-ARIA specifications, by applying the prompt WAI-ARIA roles, states, and properties along with the keyboard support. Thus, making it usable for people who use assistive WAI-ARIA Accessibility supports that is achieved through the attributes like aria-labelledby,
It helps to provides information about the elements in a document for assistive technology.
The component implements the keyboard navigation support by following the WAI-ARIA practices and tested in major screen readers.

ARIA attributes

Property	Functionality
role	Button: Attribute is set to the Accordion header elements to indicate that the element can be used to toggle the visibility of the associated content section, describing the actual role of the element. Region: Attribute is set to the Accordion panel elements to create a landmark region that contains the currently expanded accordion panel, describing the actual role of the element.
aria-labelledby	Attribute is set to content (panel) and it points to the corresponding Accordion header.
aria-controls	Attribute is set to the header and it points to the corresponding Accordion content.
aria-expanded	Attribute is set to the Accordion header elements to indicates the expand state of the Accordion Item. Default value of this attribute is false. If an item is expanded, the attribute value changes to ‘true’.
aria-hidden	Attribute is set to the Accordion panel elements to indicates the content visible state of the Accordion Item. Default value of this attribute is true. If an item content is visible, the attribute value changes to false.
aria-disabled	It indicates the disabled state of the Accordion and its items.

Keyboard interaction

Keyboard navigation is enabled by default. Possible keys are:

Key	Description
Space or Enter	When focus is on the Accordion header, click on the focused element makes the element to expand and collapse.
Down Arrow	Focus the next Accordion header.
Up Arrow	Focus the previous Accordion header.
Home	Focus the first Accordion header.
End	Focus the last Accordion header.

app.component.ts

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

@Component({
    selector: 'app-container',
    template: `
  <ejs-accordion>
        <e-accordionitems>
          <e-accordionitem expanded='true'>
            <ng-template #header>
              <div>ASP.NET</div>
            </ng-template>
            <ng-template #content>
              <div>Microsoft ASP.NET is a set of technologies in the Microsoft .NET Framework for building Web applications and XML Web
                services. ASP.NET pages execute on the server and generate markup such as HTML, WML, or XML that is sent to a desktop
                or mobile browser. ASP.NET pages use a compiled,event-driven programming model that improves performance and enables
                the separation of application logic and user interface.</div>
            </ng-template>
          </e-accordionitem>
          <e-accordionitem>
            <ng-template #header>
              <div>ASP.NET MVC</div>
            </ng-template>
            <ng-template #content>
              <div>The Model-View-Controller (MVC) architectural pattern separates an application into three main components: the model,
                the view, and the controller. The ASP.NET MVC framework provides an alternative to the ASP.NET Web Forms pattern for
                creating Web applications. The ASP.NET MVC framework is a lightweight, highly testable presentation framework that
                (as with Web Forms-based applications) is integrated with existing ASP.NET features, such as master pages and membership-based
                authentication.
              </div>
            </ng-template>
          </e-accordionitem>
          <e-accordionitem>
            <ng-template #header>
              <div>JavaScript</div>
            </ng-template>
            <ng-template #content>
              <div>JavaScript (JS) is an interpreted computer programming language.It was originally implemented as part of web browsers
                so that client-side scripts could interact with the user, control the browser, communicate asynchronously, and alter
                the document content that was displayed.More recently, however, it has become common in both game development and
                the creation of desktop applications.</div>
            </ng-template>
          </e-accordionitem>
        </e-accordionitems>
      </ejs-accordion>
        `
})

export class AppComponent {

}

app.module.ts

import { NgModule } from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';
import { AccordionModule } from '@syncfusion/ej2-angular-navigations';
import { AppComponent } from './app.component';

/**
 * Module
 */
@NgModule({
    imports: [
        BrowserModule, AccordionModule
    ],
    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);