Accessibility in Angular Context menu component

17 Nov 20226 minutes to read

The web accessibility makes web content and web applications more accessible for people with disabilities. It especially helps in dynamic content change and development of advanced user interface controls with AJAX, HTML, JavaScript, and related technologies. ContextMenu provides built-in compliance with WAI-ARIA specifications. WAI-ARIA support is achieved through attributes the like aria-expanded and aria-haspopup applied for menu item in ContextMenu. It helps the people with disabilities by providing information about the widget for assistive technology in the screen readers. ContextMenu component contains the menu role and menuItem role.

Properties	Functionality
menu	This role will be specified for an item that do not have sub menus.
menuItem	This role will be specified for an item which don’t have sub menus.
aria-haspopup	Indicates the availability and type of interactive popup element.
aria-expanded	Indicates whether the subtree can be expanded or collapsed, as well as indicates whether its current state expanded or collapsed.

Keyboard interaction

Keyboard shortcuts	Actions
Esc	Closes the opened ContextMenu.
Enter	Selects the focused menu item.
Up	Navigates up or to the previous menu item.
Down	Navigates down or to the next menu item.
Left	Close the current sub menu and navigates to the parent menu.
Right	Navigates and opens the next sub menu.

app.component.ts

import { Component } from '@angular/core';
import { getInstance } from '@syncfusion/ej2-base';
import { MenuItemModel, ContextMenu } from '@syncfusion/ej2-navigations';

@Component({
  selector: 'app-root',
  template: `
            <div id='target'>Right click / Touch hold to open the ContextMenu</div>
            <ejs-contextmenu id='contextmenu' target='#target' [items]= 'menuItems' (load)="menuOpen()"></ejs-contextmenu>`
})

export class AppComponent {
    public menuItems: MenuItemModel[] = [
        {
            text: 'Cut',
            iconCss: 'e-cm-icons e-cut'
        },
        {
            text: 'Copy',
            iconCss: 'e-cm-icons e-copy'
        },
        {
            text: 'Paste',
            iconCss: 'e-cm-icons e-paste',
            items: [
                {
                    text: 'Paste Text',
                    iconCss: 'e-cm-icons e-pastetext'
                },
                {
                    text: 'Paste Special',
                    iconCss: 'e-cm-icons e-pastespecial'
                }
            ]
        }];

     ngAfterViewInit(): void{
         setTimeout(() => {
            let contextmenuObj: ContextMenu = getInstance(document.getElementById("contextmenu_0"), ContextMenu) as ContextMenu;
            contextmenuObj.open(40, 20);
        }, 300);
     }
}

app.module.ts

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

enableRipple(true);

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