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Accessibility in a Web 2.0 World

This resource provides a comprehensive overview of web accessibility in the context of Web 2.0, focusing on key guidelines from the Web Content Accessibility Guidelines (WCAG) 2.0. It covers the importance of creating accessible content using advanced technologies like AJAX and Rich Internet Applications (RIA). The document outlines principles, guidelines, and success criteria that can help developers ensure their web applications are usable for everyone, including individuals with disabilities. It emphasizes the necessity of using high-quality components for improved accessibility and practical implementation strategies.

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Accessibility in a Web 2.0 World

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  1. Accessibility in aWeb 2.0 World (get a straw) Shawn Henry, W3C WAI

  2. Topics • Components • ATAG • WCAG 2.0 • Dynamic applications • Scripting, AJAX, RIA (rich Internet applications) • Handouts: • Expanded version • Additional URIs

  3. You ? • W3C WAI ? • WCAG 1.0 ? • WCAG 2.0 ? • ATAG ? • Screen readers ? • AJAX ? Heard of Know fairly well

  4. Want to know about: • What’s accessibility all about ? • WCAG 2.0 ? • Scripting, AJAX ?

  5. W3C WAI • World Wide Web Consortium (W3C) • International • Develops Web standards (HTML, CSS, …) • Web Accessibility Initiative (WAI) • Develops Web accessibility guidelines,international standards • www.w3.org/WAI/

  6. Components of Web Accessibility Web Content(WCAG) Authoring Tool(ATAG) User Agent(UAAG)

  7. Weak ComponentsCause Accessibility Barriers

  8. The Powerful Impact ofHigh Quality Components

  9. ACTION ! • Actively encourage improvements in authoring tools • WAI resources: • Authoring Tool Accessibility Guidelines (ATAG) • Selecting and Using Authoring Tools for Web Accessibility

  10. What’s New with WCAG Two • Applies to more advanced Web technologies • More precisely testable (still need human) • Adaptable for situations (Baseline) • Extensive supporting materials, practical implementation

  11. WCAG 1.0 Guidelines CheckpointsPriority 1, 2, 3 WCAG 2.0 Principles Guidelines Success CriteriaLevel 1, 2, 3

  12. Principles • Perceivable • Operable • Understandable • Robust

  13. Testable, Levels Example • WCAG 1.0 Checkpoint • 2.2 Ensure that foreground and background color combinations provide sufficient contrast when viewed by someone having color deficits… • WCAG 2.0 Success Criteria • 1.4.1 Text or diagrams, and their background, have a luminosity contrast ratio of at least 5:1 [Level 2] • 1.4.3 Text or diagrams, and their background, have a luminosity contrast ratio of at least 10:1 [Level 3] [Level 2]

  14. WCAG 2.0 Supporting Documents • Overview of WCAG 2.0 Documents • Techniques for WCAG 2.0 WD • WCAG 2.0 Quick Reference WD  • Understanding WCAG 2.0 WD • Coming • How to make accessible tables, forms, … • Quick Tips … • UI

  15. When? • Public Working Drafts • Last Call Working Draft • Candidate Recommendation • Implementations • Proposed Recommendation • W3C Recommendation=Web Standard

  16. Transitioning • Most sites that conform to WCAG 1.0 should not require significant changes • See WCAG 2 FAQ • Support: • "How WCAG 2.0 Drafts Differ from WCAG 1.0" section • Comparison of WCAG 1.0 Checkpoints to WCAG 2.0 • Transitioning Web Sites • Transitioning Accessibility Policies

  17. Baseline in WCAG 2.0 • Heard of • Tried to understand

  18. Understanding Baseline • First, Why • Flexibility for different situations today • Flexibility over time • For example, SVG (Scalable Vector Graphics) • WCAG Working Group is refining(expect some changes)

  19. Baseline • List of technologies • For example: HTML, CSS, etc... • That are accessible, that users have available • An established list of Web technologies that an author can use to create accessible Web content • Can use technologies outside of baseline, if content is usable without • That is, used for enhancement

  20. Topics • Components • ATAG • WCAG 2.0 • Baseline • Dynamic applications • Scripting, AJAX, RIA (coming up: additional slides since handout)

  21. Scripting, AJAX, RIA • Good news with WCAG 2 ! • Baseline

  22. Scripting Tips for Accessibility • Do automatic redirects on server side, instead of client side • Device independence, e.g., • onmouseover & onfocus • mousedown & keydown • click & keypress • mouseover & focus • mouseout & blur • Techniques for WCAG 2.0“Client-side Scripting Techniques”

  23. AJAX • Accessibility • Usability – general, for all • User doesn’t know updates will happen auto • User doesn’t notice updates • User can’t find updated info • Unexpected change in focus • Back button breaks • Can’t bookmark

  24. Demo: WCAG 2.0 Quick Reference

  25. AJAX Temperature Gauge • Not just cool, hot? Really useful to users? • ApproachDISCLAIMER: not endorse, others too, … the hows and whys of degradable ajax Progressive enhancement with Ajax • “first build your app using old-fashioned server-side technology… once you’ve got that built, you can then apply JavaScript…” • “progressive enhancement [is] how we should all be building our web apps” – Jeremy Keith

  26. AJAX • Accessibility • Usability – general, for all • User doesn’t know updates will happen auto • User doesn’t notice updates • User can’t find updated info • Unexpected change in focus • Back button breaks • Can’t bookmark

  27. Straw Activity • Some people have a very small field of vision -- called “tunnel vision”. Imagine using a complex Web page like this…

  28. Screen Magnification

  29. AJAX • Accessibility • User doesn’t know updates will happen auto • User doesn’t notice updates • User can’t find updated info • Unexpected change in focus – can’t read page • Back button breaks • Can’t bookmark

  30. Whaddyado for Now • Explain interaction • Provide options (default least problematic!) • Manual update • Notifications (e.g., dialog box) • Draw attention (e.g., “yellow fade technique”) • Set focus • Avoid automatic focus change (usually) • …

  31. More Whaddyado for Now • … • <Hx> and proper markup • Provide navigation to changes • Example:The DOM and Screen Readers(Juicystudio) Errors from Form ValidationDISCLAIMER: not endorse, others too,…

  32. Whaddyado for Later • ARIA Suite for Accessible Rich Internet Appsfrom W3C WAI Protocols & Formats WG • Some implementations already

  33. Accessibility for Dynamic Applications • Create desktop-style widgets for Webe.g., tree control • Keyboard nav (w/o excessive Tab)(benefit keyboard “power” users) • Notification of updates

  34. Dynamic Applications • DISCLAIMER: not endorse, others too,…AJAX Accessibility Overview, Becky Gibson, IBM • W3C Announces Roadmap for Accessible Rich Internet Applications (WAI-ARIA) press release • Call for Review: Accessible Rich Internet Applications (WAI-ARIA) Working Drafts e-mail • ARIA Overview (coming soon) • www.w3.org/WAI/ Highlights

  35. And so • WCAG 2.O • Better for developers • Better accessibility • Dynamic Applications • Be a showcase: Get attention, get help

  36. More: • Tomorrow 2:00Accessibility: Better, Faster, Cheaper • Responsibilities • Business Case • Black, White, Gray • Collaborators with Disabilities • Demos • Understanding Web Accessibilitybook chapterwww.uiaccess.com/understanding.html

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