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Interactive online tool for accessibility guidelines creation, share, update and evaluation.
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Transition of Accessibility Evaluation Tools to New Standards
A. Aizpurua, M. Arrue, Markel Vigo, and J. Abascal
Laboratory of HCI for Special Needs
International Cross-Disciplinary Conference on Web Accessibility, W4A 2009
University of the Basque Country
Introduction
Management FrameworkIntroduction
• The advent of WCAG 2.0 calls for accessibility guidelines review tools adaptation and update
• It is expected that international policies will adopt WCAG 2.0
• How to do this transition in the less painful way
• An interactive framework for guidelines management is provided
• Help users in the process of guideline creation and edition
Updating to WCAG 2.0
International Cross-Disciplinary Conference on Web Accessibility, W4A 2009
Conclusions
Introduction
Management FrameworkIntroduction
• Web application universally accessible from the browser
• WCAG 1.0 compliant and empowers people with disabilities to contribute
• Centralized system so that users, developers and practitioners can share information
• It contains an evaluation component
• No need for evaluation engine update
Updating to WCAG 2.0
International Cross-Disciplinary Conference on Web Accessibility, W4A 2009
Conclusions
Guidelines Management FrameworkThe foundations: Unified Guidelines Language (UGL)
• Unified Guidelines Language (UGL), a XML-based language to define guidelines.
• Developed by considering diverse guideline sets:→ General purpose: WCAG 1.0 and IBM Accessibility Guidelines→ Device: Mobile Web Best Practices 1.0→ Application: Accessible Educational Sites [Freed et al., 2003]→ Specific audiences: usability guidelines for the elderly [Kurniawan and
Zaphiris, 2005]
• Flexible enough to handle heterogeneous guidelines
• We cannot force users to learn UGL
International Cross-Disciplinary Conference on Web Accessibility, W4A 2009
Management FrameworkIntroduction Updating to WCAG 2.0 Conclusions
Guidelines Management FrameworkThe foundations: Unified Guidelines Language (UGL)
• We cannot force users to learn UGL
International Cross-Disciplinary Conference on Web Accessibility, W4A 2009
<checkpoints id="2" title="HTML elements and their attributes"><priority>1</priority><description/><evaluation_type>auto-semi</evaluation_type><techniques id="1"><type>HTML</type><description>Compulsory</description><test_case id="7">
<type>7</type><evaluation_type>auto</evaluation_type><evaluation_result>error</evaluation_result><element>
<label>IMG</label><test_e>check attribute</test_e><related_attribute>
<atb>alt</atb><test_a>compulsory</test_a>
</related_attribute></element>
</test_case></techniques><techniques id="2”><test_case id="8">
<type>8</type><evaluation_type>auto</evaluation_type><evaluation_result>error</evaluation_result><element>
<label>FRAME</label><test_e>check attribute</test_e><related_attribute>
<atb>title</atb><test_a>compulsory</test_a><content analysis="not empty"/>
Management FrameworkIntroduction Updating to WCAG 2.0 Conclusions
Guidelines Management FrameworkGuidelines Definition Manager
• Technique edition: “for each id attribute in textarea check there is a label where for=id”
International Cross-Disciplinary Conference on Web Accessibility, W4A 2009
1. select textarea tag
Management FrameworkIntroduction Updating to WCAG 2.0 Conclusions
Guidelines Management FrameworkGuidelines Definition Manager
• Technique edition: “for each id attribute in textarea check there is a label where for=id”
International Cross-Disciplinary Conference on Web Accessibility, W4A 2009
1. select textarea tag2. select id attribute
Management FrameworkIntroduction Updating to WCAG 2.0 Conclusions
Guidelines Management FrameworkGuidelines Definition Manager
• Technique edition: “for each id attribute in textarea check there is a label where for=id”
International Cross-Disciplinary Conference on Web Accessibility, W4A 2009
1. select textarea tag2. select id attribute3. select label tag
Management FrameworkIntroduction Updating to WCAG 2.0 Conclusions
Guidelines Management FrameworkGuidelines Definition Manager
• Technique edition: “for each id attribute in textarea check there is a label where for=id”
International Cross-Disciplinary Conference on Web Accessibility, W4A 2009
1. select textarea tag2. select id attribute3. select label tag4. select for attribute
Management FrameworkIntroduction Updating to WCAG 2.0 Conclusions
Guidelines Management FrameworkGuidelines Definition Manager
• Technique edition: “for each id attribute in textarea check there is a label where for=id”
International Cross-Disciplinary Conference on Web Accessibility, W4A 2009
1. select textarea tag2. select id attribute3. select label tag4. select for attribute 5. define element order
Management FrameworkIntroduction Updating to WCAG 2.0 Conclusions
Guidelines Management FrameworkGuidelines Definition Manager
• Guidelines can be shared: general search, specific search, mark-up dependent search
International Cross-Disciplinary Conference on Web Accessibility, W4A 2009
Management FrameworkIntroduction Updating to WCAG 2.0 Conclusions
Guidelines Management FrameworkGuidelines Definition Manager
• Search results: guidelines can be retrieved, edited and used
International Cross-Disciplinary Conference on Web Accessibility, W4A 2009
Management FrameworkIntroduction Updating to WCAG 2.0 Conclusions
Guidelines Management FrameworkGuidelines Pre-processor
• Created guidelines are stored in a centralized database• Data are transformed into UGL files• Decompose resulting UGL file into XQuery queries• This process does not require human intervention
International Cross-Disciplinary Conference on Web Accessibility, W4A 2009
Guidelines Evaluation Component• Select the guidelines• Type URL• Evaluation type:
1. single URL2. website3. source code
Management FrameworkIntroduction Updating to WCAG 2.0 Conclusions
Guidelines Management FrameworkGuidelines Pre-processor
• Created guidelines are stored in a centralized database• Data are transformed into UGL files• Decompose resulting UGL file into XQuery queries• This process does not require human intervention
International Cross-Disciplinary Conference on Web Accessibility, W4A 2009
Guidelines Evaluation Component• Select the guidelines• Type URL• Evaluation type:
1. single URL2. website3. source code
Management FrameworkIntroduction Updating to WCAG 2.0 Conclusions
user B
user A
Guidelines Management FrameworkSummary
1: user A creates, searches, shares guidelines
International Cross-Disciplinary Conference on Web Accessibility, W4A 2009
Definition manager
· create· search· share· update
· select guidelines· evaluate
Evaluation component
Guidelinespre-processor
browser server
XQuery1
XQuery2
XQueryn
XQueryi
......
get XQuery2
get XQueryn
Guidelines
repository
1 2
3
5
2: guidelines are stored in a remote repository3: guidelines are transformed into UGL4: UGL are decomposed into XQuery
4
5: user B selects guidelines and evaluates web page
Management FrameworkIntroduction Updating to WCAG 2.0 Conclusions
Updating to WCAG 2.0• Case study with WCAG 2.0
• Taking advantage of the features of the guidelines management framework
• Test-case definition: ”Test-cases are the minimum pieces of knowledge required for the evaluation of guidelines”
1. guidelines evaluation techniques test cases2. XHTML tag or attribute dependent3. Test-cases can be grouped into test-case types
IMG [@alt] TABLE [@summary]
4. there is a predefined evaluation pattern for each test-case type
• Focusing on automatic and semi-automatic issue
International Cross-Disciplinary Conference on Web Accessibility, W4A 2009
Management FrameworkIntroduction Updating to WCAG 2.0 Conclusions
Updating to WCAG 2.0• Decomposing success criteria into test-cases
International Cross-Disciplinary Conference on Web Accessibility, W4A 2009
PrincipleSuccess criteria
automatictest-cases
semi-automatic test-cases
Perceivable 22 17 38
Operable 20 8 16
Understandable 17 10 9
Robust 2 4 3
Total 61 39 66
• Results obtained with the guidelines management framework: Automatic test-cases: 55% Semi-automatic: 16%
Management FrameworkIntroduction Updating to WCAG 2.0 Conclusions
Updating to WCAG 2.0
International Cross-Disciplinary Conference on Web Accessibility, W4A 2009
• Results obtained with the guidelines management framework: Automatic test-cases: 55% Semi-automatic: 16%
• It is not a limitation of UGL but of the management framework
• They can be manually included
• By adapting the framework almost all automatic test cases can be defined
• Except those that are not hypertext dependent E.g.:”check that the value of longdesc is a valid URI ”
• Strike a balance between guiding the user or letting him free
Management FrameworkIntroduction Updating to WCAG 2.0 Conclusions
Conclusions
• The framework for guidelines management is a sound tool to share and spread knowledge on web accessibility
• Cooperative tool enabling collaboration between researchers, practitioners and users
• It can be used in the development process for: Search for the set of guidelines which is relevant to the current
development Remove guideline overlap and verify coherence Perform frequent accessibility evaluations
• WCAG 2.0 deployment has been less painful
• Updating the framework in order to express more test-cases
International Cross-Disciplinary Conference on Web Accessibility, W4A 2009
Management FrameworkIntroduction Updating to WCAG 2.0 Conclusions
A. Aizpurua, M. Arrue, Markel Vigo, and J. Abascal
Laboratory of HCI for Special Needs
International Cross-Disciplinary Conference on Web Accessibility, W4A 2009
University of the Basque Country
Any question?
Transition of Accessibility Evaluation Tools to New Standards