WAI-ARIA provides semantics and accessibility information to web pages and applications developed with technologies like HTML, JavaScript, and CSS. It defines roles, states, and properties that can be applied to elements to define their purpose and relationships. This allows assistive technologies like screen readers to better understand the structure, functionality and relationships within complex JavaScript-driven applications and dynamic content.

1. WAI-ARIA is more
than Accessibility
othree @ COSCUP 2011

2. Who am I
Member of Happy Designer
MozTW
HTML5-IG-ZH
Work PhD Candidate on Civil
F2E at HTC

3. The History

4. Web 2.0

5. Age ofRich Internet Applications
RIA

6. Custom Widgets

12. AJAX

16. Problems
• Custom Widgets
• No Semantic, Browser/AT didn’t realize
• Can’t get focus

21. Problem
• AJAX
• AT didn’t know when the content
changes, and where is it.

22. WAI-ARIA

23. WAI-ARIA
• Proposed by Richard Schwerdtfeger from
IBM and Becky Gibson from W3C
• W3C Candidate Recommendation at
2011/01/18
• You can use it TODAY
http://www.alistapart.com/articles/waiaria

24. Components of ARIA
• role → browser knows meaning
• states and properties → browser knows
• redefine tabindex → possible to focus
• liveregion → notice when content changes

25. Mapping to Problems
• role → browser knows meaning
• states and properties → browser knows
• redefine tabindex → possible to focus
• liveregion → notice when content changes

26. Mapping to Problems
• role → define new rolesmeaning
browser knows
• states and properties → browser knows
• redefine tabindex → possible to focus
• liveregion → notice when content changes

27. Mapping to Problems
• role → define new rolesmeaning
browser knows
• states and properties → store states
browser knows
• redefine tabindex → possible to focus
• liveregion → notice when content changes

28. Mapping to Problems
• role → define new rolesmeaning
browser knows
• states and properties → store states
browser knows
• redefine tabindex → possible to focus
• liveregion → notice when content changes

29. Mapping to Problems
• role → define new rolesmeaning
browser knows
• states and properties → store states
browser knows
• redefine tabindex → possible to focus
• liveregion → notice when content changes

30. Role

31. Role, role of element
• alert • scrollbar
• button • slider
• checkbox • tab
• dialog • timer
• link • tooltip
• menuitem • ...

33. Slider
<span
tabindex="0"
role="slider"
aria-valuenow="33"
aria-valuemin="0"
aria-valuemax="50"
id="slider1" title="My slider"
onkeydown="return handleSliderKey(this, event)">
--
</span>

34. Slider
<span
tabindex="0"
role="slider"
aria-valuenow="33"
aria-valuemin="0"
aria-valuemax="50"
id="slider1" title="My slider"
onkeydown="return handleSliderKey(this, event)">
--
</span>

35. Role, more than widget
• Widgets Roles
• Document Structure
• Landmark

36. Document Structure
Landmark
• article • banner
• heading • complementary
• img • contentinfo
• list • main
• note • navigation
• presentation • search

37. HTML5 Semantic Tag
<header>
<nav>
<aside>
<article>

38. ARIA Document Structure
banner
navigation
complementary
main

39. Difference
ARIA HTML5
Banner for
banner <header> Head of section
entire site
Main content of
main <article> An article
page

40. HTML5 + ARIA
<div role=”banner”>
<nav>
<div role=”main”>
<aside>
<article>
</div>

41. ARIA can help
HTML5 document
more semantic

42. States & Properties

44. <div id="master" style=".." class="..">
<div class=".." style="width: 60%;"></div>
<a class=".." href="#" style="left: 60%;"></a>
</div>

45. <div id="master" style=".." class="..">
<div class=".." style="width: 60%;"></div>
<a class=".." href="#" style="left: 60%;"></a>
</div>

46. <div id="master" style=".." class="..">
<div class=".." style="width: 60%;"></div>
<a class=".." href="#" style="left: 60%;"></a>
</div>

47. Store Methods
• Use DOM Node property
• Use custom class
• Use custom attribute
• Use Widget controller
• Use centralized storage system

48. ARIA slider
<span
tabindex="0"
role="slider"
aria-valuenow="33"
aria-valuemin="0"
aria-valuemax="50"
id="slider1" title="My slider"
onkeydown="return handleSliderKey(this, event)">
--
</span>

49. ARIA slider
<span
tabindex="0"
role="slider"
aria-valuenow="33"
aria-valuemin="0"
aria-valuemax="50"
id="slider1" title="My slider"
onkeydown="return handleSliderKey(this, event)">
--
</span>

50. ARIA slider
<span
tabindex="0"
role="slider"
aria-valuenow="33"
aria-valuemin="0"
aria-valuemax="50"
id="slider1" title="My slider"
onkeydown="return handleSliderKey(this, event)">
--
</span>

51. ARIA slider
<span
tabindex="0"
role="slider"
aria-valuenow="33"
aria-valuemin="0"
aria-valuemax="50"
id="slider1" title="My slider"
onkeydown="return handleSliderKey(this, event)">
--
</span>

52. Also for Relationships
• label, describe
• owns, controlls

55. ?

56. ?
?

57. label, describe
<a href="http://yahoo.com" id="yahoo-link-2"
aria-describedby="tooltip">Link to yahoo1</a>
.
.
.
<div id="tooltip" aria-labelledby="yahoo-link-2">
<h3>Yahoo doo2</h3>
<div class="body">wohooo</div>
<div class="url" style="display: none; "></div>
</div>

58. label, describe
<a href="http://yahoo.com" id="yahoo-link-2"
aria-describedby="tooltip">Link to yahoo1</a>
.
.
.
<div id="tooltip" aria-labelledby="yahoo-link-2">
<h3>Yahoo doo2</h3>
<div class="body">wohooo</div>
<div class="url" style="display: none; "></div>
</div>

59. Live Region

60. Live Region
• Monitor DOM change
• How?
• aria-live=”polite”

61. Polite Level
• off
• polite
• assertive
• rude

62. Tabindex

63. Redefine Tabindex
• Available for all visible elements
• Three values
• >0
• 0→
• -1 →

64. Redefine Tabindex
• Available for all visible elements
• Three values
• >0
• 0 → in native order
• -1 →

65. Redefine Tabindex
• Available for all visible elements
• Three values
• >0
• 0 → in native order
• -1 → need .focus()

67. ←START

68. 1
Tab Order
2 3 4 5 6
7...

69. 1
Ideal Tab Order
2
3

70. Move to Other Tab
→

71. Move to Other Tab
← →

73. Tabindex Value
0 -1 -1 -1 -1

74. Tabindex Value
-1 0 -1 -1 -1

75. Not automatically

76. More than Accessibility

77. SEO
• Document Structure & Landmark Role
• Yahoo! supports
• Google use role too

78. Standard Way to Store
Property & State
• Avoid pollute DOM Node & className
• Build relationship between nodes

79. Use WAI-ARIA Today!!

80. Thank You

81. Questions?