Accessibility

Aria UI treats accessibility as part of the component contract. Each primitive is designed so the hard interaction details are handled close to the source: semantic structure, keyboard paths, focus movement, disabled states, and state attributes that can be styled without changing behavior.

The goal is not to make accessibility invisible. The goal is to make the expected behavior explicit enough that product teams can compose interfaces with confidence and still keep responsibility for copy, layout, contrast, labeling, and the final user experience.

Accessibility model

Aria UI uses a native-first model:

• use native HTML controls whenever the platform already provides the right behavior
• add WAI-ARIA roles, states, and properties when a composite widget needs richer semantics
• expose predictable data attributes so visual states can follow interaction states
• keep pointer, keyboard, and assistive technology paths aligned

For composite patterns, Aria UI follows the WAI-ARIA Authoring Practices Guide (APG) where it applies. Patterns such as dialogs, menus, tabs, listboxes, sliders, and tree views have expected keyboard and focus behavior; the primitives encode those expectations so each implementation does not have to rediscover them.

Keyboard interaction

Every interactive pattern should have a non-pointer path. Aria UI components define keyboard behavior at the primitive level so the same interaction works consistently across examples and product surfaces.

• Tab moves through focusable controls in document order
• arrow keys move inside composite widgets when the pattern calls for roving focus or active selection
• Enter and Space activate the expected item, trigger, or control
• Escape dismisses transient UI such as menus, dialogs, popovers, and comboboxes
• Home and End move to the first or last item where the pattern supports ordered navigation

Keyboard behavior is part of the public contract for each component. When a package has additional key bindings, the component documentation lists them in the keyboard section.

Focus management

Focus should always have a clear place to go. Components that open transient surfaces move focus intentionally, keep focus inside the active surface when needed, and return focus to a sensible element when the surface closes.

This matters most for overlays and composite widgets:

• dialogs should focus meaningful content when they open and return focus to the trigger when they close
• menus and popovers should support dismissal without stranding focus
• listboxes, tabs, tree views, and grids should keep active navigation understandable
• disabled items should remain visually clear without becoming accidental tab stops

Aria UI exposes the behavior layer, but your application still owns the visible focus treatment. Focus rings should be easy to spot, meet contrast expectations, and remain visible in dense layouts.

State and semantics

Accessible behavior depends on the DOM communicating the same state the user sees. Aria UI primitives use semantic elements first, then add ARIA attributes where state needs to be announced or navigated by assistive technology.

Common state includes:

• expanded or collapsed content
• selected, checked, pressed, or current items
• disabled controls
• invalid or required form fields
• modal and non-modal overlay state

The same state is also exposed through data attributes where appropriate. That lets you style open, closed, selected, disabled, and similar states without changing the markup or duplicating state in application code.

What your app still owns

Aria UI can provide accessible primitives, but it cannot guarantee the final page is accessible. The surrounding product still controls context, hierarchy, language, and visual quality.

Before shipping an interface, check that you have:

• clear labels and descriptions for controls
• heading order that matches the page structure
• sufficient color contrast in every state
• visible focus indicators that are not hidden by layout or overflow
• error messages that identify the field and explain the fix
• announcements for async changes, loading states, and destructive actions when needed
• touch targets and spacing that work on small screens

Accessibility is a system property. The primitive can make the correct behavior easier to reuse, but the final result still needs design review, keyboard testing, screen reader checks, and product judgment.

Testing expectations

Treat accessibility testing as part of normal component work. At minimum, verify each interactive flow with a keyboard, inspect focus movement, and check that visible state matches DOM state. Automated tools can catch many structural issues, but they do not replace manual testing with the actual interaction pattern.

For component-level work, prefer tests that exercise behavior instead of snapshots: open and close the surface, move through items with the keyboard, assert focus placement, and confirm disabled or selected states are reflected in the DOM. For application work, test the composed experience in the real layout where overflow, stacking, and visual contrast can change the outcome.