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Testing for Accessibility

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Testing for Accessibility Powered By Docstoc
					     Testing for
   Accessibility and
      Usability

Is Your Site Accessible and Usable
       or Just Conformant?
         Presenters
Jason White – Co-Chair, Web Content
Accessibility Guidelines Working Group
Naomi Heagney – The Hiser Group
Andrew Arch – Vision Australia Foundation
W3C and Accessibility
Success Criteria


      Jason White
          WCAG 1.0
Issues with conformance
              WCAG 2.0
Testable success criteria
   Abstraction and specificity
Definition of testability
   Either machine testable or human testable
Introduction of review requirements into
success criteria
   E.g. text equivalent
    WCAG 2.0 continued
WCAG 2.0 is multi layered
 Design principles
 Guidelines and Checkpoints
 Techniques for technologies

Test cases as part of techniques
 Machine testable
 Human testable
 Non-testable
A Usability
Perspective


     Naomi Heagney
Usability & Accessibility
What is Usability?
Similarities and differences
  Focus
  Resources

  Method

  Standards and legislation
     What is Usability?
Usability is the extent to which a product
can be used by specified users to achieve
specified goals with effectiveness,
efficiency and satisfaction in a specified
context of use.
              – Definition from ISO 9241-11
      What is Usability?
User Centred Design (UCD) is an
iterative and collaborative methodology:
  Analysis
  Design

  Evaluation


Usability is not just “lab testing”
    Reviews, walkthroughs, in-situ testing
          Similarities
The people
Involvement in development processes
 Integrated
 The earlier the better

Need knowledge of:
 Target audience
 Personal characteristics
            Differences
Focus
 Conformance versus site improvement
 Qualitative & quantitative data

 Measures for usability are project-specific

Resources
   Different specialist knowledge required
           Differences
Evaluation methods
  Less emphasis on automated tools
  Variety of techniques, scalable to project
   constraints
Standards & legislation
  Focus on process rather than product
  WCAG & checkpoints provide excellent
   basis for legislative support
Accessibility Testing



      Andrew Arch
Concept and Design
     Review
Critical consideration of end-to-end
process
Identify:
 Objective
 Options for implementation

Assess strategies that could be used
   Consider requirements on the user
    Manual Checking

Requires knowledge and understanding
Involves:
  Reviewing content

  Reviewing code

  User testing
Site Testing by Assistive
    Technology Users
Complements technical accessibility testing,
but does not replace it.
Purpose is to appreciate usability issues for
users of assistive technology.
User testing CANNOT determine if a site or
online object works with all assistive
technology.
User testers need to be skilled, but not expert
with their technology.
Technical Accessibility
      Checking
 Automated Tools
   All do a partial job

   All have flaws or weaknesses

   Interpretation needed (manual
    checking and rectification)
 Many “pseudo tools” are available by
 using the options included as standard
 within your computer
 Evaluation & Repair
        Tools
 Browser   settings            A-Prompt

 Built-in checking             Tidy

 Colour checkers               Code  validators
 Link checkers                 Commercial

 The Wave                       Tools

Full list: http://www.w3.org/WAI/ER/existingtools.html
    Pseudo Tools –
Browser Setting Options
Change the font to a larger size
View pages without images
View pages with styles sheets and pages
colours/fonts disabled
View pages with an alternative, high contrast,
colour scheme
Use the keyboard not the mouse to navigate
Disable scripts, applets and/or plugins
Try different browsers & versions
Built in Checking –
eg. Dreamweaver




See also WAI Authoring Tools guidelines
       Colour Checkers
Colour Contrast
   http://www.lighthouse.org/
    color_contrast.htm
   http://aprompt.snow.utoronto.ca/
    ColorVisibilityProgram.html (Beta version)
Colour tester – colour blind
   http://www.tesspub.com/colours.html
   http://www.vischeck.com/
Legible text
   http://www.lighthouse.org/print_leg.htm
       Link Checkers
Link checkers: non-existent URLs
    http://www.linkalarm.com/
    http://www.tetranetsoftware.com/
     solutions/linkbot/looking-for-linkbot.asp
    http://www.cyberspyder.com/cslnkts1.html

    http://validator.w3.org/checklink

Cannot check for incorrect addresses
                 The Wave
Pros                               Cons
   Visual                             No fixes
   Shows reading order                No
   Shows logical                       recommendations
    structure
   Shows suspect ALT
    text
   Identifies scripts as a
    potential accessibility
    issue
 http://www.temple.edu/inst_disabilities/piat/wave/
                 A-Prompt
Pros                     Cons
   Offers repairs          Slow to use
   Alt text registry       Repairs code
                            Interactive




http://www.aprompt.ca/
                     Tidy
 Pros
     Offers to fix code        Pros …cont
                                   GUI front-end
    Formats HTML
                                     available
    Works with
                                   Interfaces with
      HTML/XHTML/
                                     several authoring
    Cleans up Word
                                     tools
      conversions
    Advice on
                                Cons
      accessibility &              Very technical

      internationalisation
http://www.w3.org/people/Raggett/tidy/
         Code Validators

HTML Validator
 W3C: http://validator.w3.org/
 NetMechanic, WebDesignGroup

CSS Validator
   http://jigsaw.w3.org/css-validator/
SMIL Validator
   http://www.cwi.nl/~media/symm/validator/
Site Evaluation & Repair Tools
 (Commercial, but with free limited checks or trials)

     Bobby (Watchfire)
        http://bobby.watchfire.com/bobby/html/en/
         index.jsp
     Lift Online (Usablenet)
        http://www.usablenet.com/
     Ask Alice (SSB Technology)
        http://askalice.ssbtechnologies.com:8080/
         askalice/index.html
     Accverify (HiSoftware)
        http://www.hisoftware.com/access/sitetest.htm
Things to consider
       Management
      Considerations
How much will it cost?
What can “I” do?
Where do we need help?
What is the developers role?
What can I expect of “off the shelf”
software?
What about outsourced sites?
             References
Evaluating Websites for Accessibility
http://www.w3.org/WAI/eval/Overview.html
The WAVE
http://www.temple.edu/instituteondisabilities/piat/wave/
Tidy
http://tidy.sourceforge.net/
A-Prompt
http://www.aprompt.ca/

				
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