APG Patterns
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日本語 GitHub

Breadcrumb

A navigation pattern that shows the user's current location within a site hierarchy.

🤖 AI Implementation Guide
Svelte

Demo

Basic Breadcrumb

A simple breadcrumb trail showing the path to the current page.

Long Path

A deeper navigation path with multiple levels of hierarchy.

Accessibility Features

WAI-ARIA Roles

Role Target Element Description
navigation <nav> element Provides a navigation landmark for assistive technology (implicit role of <nav>)

WAI-ARIA Breadcrumb Pattern (opens in new tab)

WAI-ARIA Properties

Attribute Target Values Required Description
aria-label <nav> "Breadcrumb" (or localized) Yes Labels the navigation landmark for screen readers
aria-current Current page element "page" Yes (on last item) Identifies the current page within the breadcrumb trail

WAI-ARIA States

aria-current="page"

Indicates the current page location within the breadcrumb navigation.

Target Last item in the breadcrumb (current page)
Values "page"
Required Yes
Reference aria-current (opens in new tab)

Keyboard Support

Key Action
Tab Move focus between breadcrumb links
Enter Activate the focused link

Breadcrumb uses native <a> element behavior for keyboard interaction. No additional keyboard handlers are required.

Source Code

Breadcrumb.svelte 
<script lang="ts">
  /**
   * Breadcrumb component following WAI-ARIA APG pattern
   * @see https://www.w3.org/WAI/ARIA/apg/patterns/breadcrumb/
   */

  export interface BreadcrumbItem {
    label: string;
    href?: string;
  }

  interface Props {
    items: BreadcrumbItem[];
    ariaLabel?: string;
    class?: string;
  }

  let { items, ariaLabel = 'Breadcrumb', class: className }: Props = $props();

  function getItemKey(item: BreadcrumbItem): string {
    return `${item.href ?? 'current'}-${item.label}`;
  }
</script>

{#if items.length > 0}
  <nav aria-label={ariaLabel} class="apg-breadcrumb {className ?? ''}">
    <ol class="apg-breadcrumb-list">
      {#each items as item, index (getItemKey(item))}
        <li class="apg-breadcrumb-item">
          {#if item.href && index !== items.length - 1}
            <a href={item.href} class="apg-breadcrumb-link">
              {item.label}
            </a>
          {:else}
            <span
              aria-current={index === items.length - 1 ? 'page' : undefined}
              class="apg-breadcrumb-current"
            >
              {item.label}
            </span>
          {/if}
        </li>
      {/each}
    </ol>
  </nav>
{/if}

Usage

Example 
<script>
  import Breadcrumb from './Breadcrumb.svelte';

  const items = [
    { label: 'Home', href: '/' },
    { label: 'Products', href: '/products' },
    { label: 'Current Product' }
  ];
</script>

<Breadcrumb {items} />

API

Props

Prop Type Default Description
items BreadcrumbItem[] required Array of breadcrumb items
ariaLabel string "Breadcrumb" Accessible label for the navigation

BreadcrumbItem

Property Type Required Description
label string Yes Display text for the item
href string No URL for the link (omit for current page)

Testing

Tests verify APG compliance across ARIA attributes, semantic structure, and accessibility requirements.

Test Categories

High Priority: APG ARIA Attributes

Test Description
nav element Uses semantic <nav> element
aria-label Navigation has accessible label (default: "Breadcrumb")
aria-current="page" Last item has aria-current="page"
ol/li structure Uses ordered list for proper semantic structure

High Priority: Keyboard Interaction

Test Description
Tab navigation Tab moves focus between breadcrumb links
Enter activation Enter key activates focused link
Current page not focusable Last item (span) is not in tab order

Medium Priority: Accessibility

Test Description
axe violations No WCAG 2.1 AA violations (via jest-axe)
Custom aria-label Can override default label via ariaLabel prop
Separator hidden Visual separators are hidden from assistive technology

Low Priority: Component Behavior

Test Description
Renders all items All provided items are rendered in order
Links have href Non-current items render as links with correct href
className merge Custom classes are merged with component classes

Testing Tools

See testing-strategy.md (opens in new tab) for full documentation.

Resources