Transcript before_sr_testing_final - Accessing Higher Ground

Testing for Accessibility
with Common Screen
Readers
•
Hadi Rangin, University of Washington
•
Robert Beach, Kansas City Kansas Community College
•
Lucy Greco, University of California, Berkeley
•
Terrill Thompson, University of Washington
•
Karen McCall, Karlen Communications
Preview
•
Technical vs Functional Accessibility
•
Definition of “Accessible”
•
IT Accessibility Standards
•
Basic Accessibility Considerations
•
Tools & Resources
Technical accessibility
• Is the coding practice according to the standard (WCAG)?
•
Ensures assistive technologies can effectively interact with
the application
“Does a particular button in the user interface present itself
in a way so that it can be understood by, and interacted using
both visual and non-visual means?”
•
•
Limitation: does not take a holistic view of determining if the
pieces of an application work together and if the end user can
complete the task effectively in a timely fashion.
Functional accessibility
•
Can the end user accomplish a task to effectively and
efficiently use an application, regardless of coding
technique?
•
“Can a user successfully compose and send an email to a
desired recipient?”
•
Functional accessibility success if the task can be
completed by various mode of interactions (mouse,
keyboard & AT)
Technical vs Functional Accessibility
•
Accessible techniques are required, but not sufficient
•
Usability with accessibility consideration
•
Both aspects are necessary in developing an accessible
application
Definition of “Accessible”
“Accessible” means a person with a disability is
afforded the opportunity to acquire the same information,
engage in the same interactions, & enjoy the same services
as a person without a disability in an equally effective &
equally integrated manner, with substantially equivalent ease
of use. The person with a disability must be able to obtain the
information as fully, equally & independently as a person
without a disability.
IT Accessibility Standards
•
World Wide Web Consortium (W3C)
 Web Content Accessibility Guidelines 1.0 (1999)
 Web Content Accessibility Guidelines 2.0 (2008)
•
Section 508 Standards
 Published in 2000 to accompany Section 508 of the Rehabilitation Act
(requires federal agencies to procure accessible IT)
 Covers a broader scope of IT, not just Web
 Many states & higher education institutions have adopted either
WCAG 2.0 or Section 508 as their own standard for IT accessibility
Screen readers:
Magic or confusing tool?
• SR
made for end-user
• 100s
of functions to assist end-users
• Complicated
algorithm to compensate for lack of
accessibility features
• SR
can be sometimes used to verify issues but not
to determine issues
• Not
designed for accessibility testing
Don’t use it for testing unless you
know what you are doing
• Bottom-line:
Things We Should Consider before
Testing (1/2)
• Understand
• Focus
the basics of coding practice
on Functional accessibility
• Familiarize
yourself with Universal Design in your
accessibility solutions
• Differentiate
between your personal preferences
and accessibility solutions
Things We Should Consider before
Testing (2/2)
• Utilize
developer & accessibility tools for technical
accessibility
• SR
can help you partially with technical
accessibility
• Work-around
• Don’t
• Be
is not an accessibility solution
get lost in your testing and evaluation
constructive in your report
Consistency
•
Visual consistency
•
Functional consistency
•
Proper use of elements
Keyboard Operability
•
Be able to navigate to all focusable elements
•
Be able to fully perform all applicable functions
•
Links, Forms controls, Menu, Expand/collapse,
Carousel, Modal, Custom widgets, etc.
•
Be able to always to see the visual focus indicator
•
Logical tab order
•
Shortcut keys alone do not make application
accessible
ARIA Landmarks
•
Integrity of ARIA landmarks throughout the application
•
No orphaned content
•
Meaningful labels
Heading Structure
•
Hierarchical
•
Meaningful
•
Inclusiveness
Lists
•
Group relevant items
•
Use appropriate list type (ordered, unordered & definition lists)
Links
•
Meaningful link text
•
Not short, not long, not empty
•
Distinctive hover effect and keyboard focus
•
Link vs button
•
Alt text for icon links
•
Links to external resources
Forms
•
Meaningful form control labels
•
Required
•
Verification and error handling
Data Tables
•
Simple vs complex data tables
•
Cell and column/row headers (association)
•
TH/SCOPE technique
•
ID/HEADERS association technique
•
Can be tested nicely with screen readers
Graphics
•
Meaningful text for informational graphics
•
Keep stylistic graphics in the background, so screen readers ignore them:
 CSS background images
 alt=""
 role="presentation"
Color Contrast
•
Adequate color contrast between foreground (text or graphic) and
background
•
WCAG 2.0 Level AA has very specific requirements:
 A 4.5:1 contrast ratio for normal sized text
 A 3:1 contrast ratio for large text (at least 18 point or 14 point bold)
Tools
•
AInspector Toolbar
 http://ainspector.github.io/
•
WAVE Web Accessibility Evaluation Tool
 http://wave.webaim.org/
• How
to use keyboard-only
 http://nomouse.org
•
Color Contrast Checker
 http://webaim.org/resources/contrastchecker/
•
WC3 Markup Validator
 https://validator.w3.org/
Resources
•
WCAG 2.0 Guideline
 https://www.w3.org/TR/WCAG20/
•
Accessible Widgets Best Practices with ARIA
 https://www.w3.org/TR/wai-aria-practices-1.1/
•
Examples of Accessible Widgets
 http://oaa-accessibility.org/
•
W3C Notes on using ARIA in HTML
 http://w3c.github.io/aria-in-html/
More Resources
•
NVDA Keyboard Commands
 http://terrillthompson.com/tests/keycounts/nvda.html
•
JAWS Keyboard Commands
 http://doccenter.freedomscientific.com/doccenter/archives/training/jaws
keystrokes.htm
•
VoiceOver: Getting Started
 https://www.apple.com/voiceover/info/guide/
Questions?