20101007_AEGIS_Sevilla

Web Accessibility from a software engineering perspective: how RIAs and the Mobile Web changed accessibility testing

Dr. Carlos A. Velasco

Fraunhofer Institute for Applied Information Technology FITWeb Compliance Center – http://imergo.com/

1st International AEGIS Conference7-8 October 2010, Sevilla

About Fraunhofer FIT

— Fraunhofer Society— Fraunhofer Institute for

Applied Information Technology FIT

Web Compliance Center

Research Area “Life Science Informatics”

Work areas

— Web Compliance Engineering

SOA/ECMS – Systems' implementation

Quality Assurance

UIs (accessibility, usability; biofeedback and therapeutical intervention systems)

— Standards bodies (W3C)

— Development & commercialization of software

— Consultancy & training: industry/public sector

— Interdisciplinary team:

Computer science

Pedagogics

Linguistics

Engineering

Software/Web engineering

— Software engineering:«… is a profession dedicated to designing, implementing, and modifying software so that it is of higher quality, more affordable, maintainable, and faster to build.» (Wikipedia)

— Web Engineering«The application of systematic, disciplined and quantifiable approaches to the cost-effective development and evolution of high-quality solutions in the World Wide Web.»

What is the Web?

«Web Science, the science of decentralised information systems.»

(A Framework for Web Science,Tim Berners-Lee et al.)

Web pre-, prehistory: WorldWideWeb Browser

Web prehistory: Mosaic Web browser

Web of the «End of the Century»

Web 2.0

What is Web Accessibility?

«Web accessibility means that people with disabilities can use the Web.»

(W3C/WAI)

Components of the Web

Components of the Web 2.0

2W

Compliance: what to test?

Web Compliance in general

Electronic Ledger Storage Law (Japan)

11MEDIS-DC (Japan)

CanadianElectronic

Evidence Act

SEC 17a-4 (USA)

HIPAA (USA)

FDA 21 CRF Part 11

ISO 18501/18509

Sarbanes-Oxley Act (USA)

AIPA (Italy)

GDPdU & GoBS (Germany)

BSI PD0008 (UK)

PublicRecords

Office (UK)

NF Z 42-013 (France)

FinancialServices

Authority (UK)

Basel IICapitalAccord

Accessibility compliance

Device compliance and ...

MobileOK

Corporate Identity

SEO

Testing Web 1.0

— Static pages

Only form interaction

— Limited layout possibilities

— Limited CSS implementation

— Poor JS support in AT: JS was «evil»

— UAs swallowed anything

Web = poorest & more successful software product of the history

— Poorly defined criteria («until UAs ...»)

— Poor object models implementation

… and the RIAs arrived

— Technology Penetration Report (Security Space, 2009-09-01, 1,485,767 web sites)

Technology Sites Percentage

JavaScript 955,494 64.31%

Frames 150,439 10.13%

StyleSheets 942,486 63.43%

Java 8,609 0.58%

Iframes 227,627 15.32%

GIF Images 918,961 61.85%

JPG Images 847,491 57.04%

PNG Images 293,430 19.75%

Flash/Shock. 183,363 12.34%

RIA Characteristics

— Ubiquitous clients: desktop, mobile, …

— Self-adapted across different platforms

— Function in low bandwidth connections

— Restore processing power to the client

— Deliver engaging UIs: interactivity

— Utilize seamlessly audio, video, images and text

— Support the mobile workflow

— Asynchronous content retrieval

— Access multiple middle tier services and backend data stores: Web Services

— Integrate with legacy applications and systems

— Allow for the incremental addition of new functions

The problem with HTML interfaces ...

— Accessibility relies on abstracting semantics from both content and presentational information

Semantic cues from HTML are unreliable (tag elements names)

— HTML allows content to be repurposed for:

presentational formatting (e.g., tables instead style sheets)

dynamic custom components (e.g., combined with script and CSS)

— HTML lacks the ability to attach meaningful metadata about document structure

— HTML elements commonly used for repurposing produce custom components not keyboard accessible

Testing Web 2.0

ARIA: filling the gaps

— Separation of content and presentation— States and Property attributes

Full keyboard focus

Mapping to accessibility APIS (passive monitoring of the application by AT)

— Role attribute

Machine-readable information about purpose of an element

— Role document landmark values— Taxonomy of ARIA role values (Semantic Web)

The contract model: accessibility APIs

Challenges for a compliance tool

— Direct interaction with the server vs. accessing OS accessibility APIs

— Emulation of user behaviour

Collect document landmarks (role taxonomy, derived from abstract roles): Widget Roles

Document Structure Roles

Landmark Roles

Monitor WAI-ARIA states and properties (modifiable via JS events): Managed (user-agent controlled)

Unmanaged (author controlled)

Focus management

Roles' summary

Type of tests

— Automatic— Expert— Users

(See UWEM)

Testing workflow

Authoring Tool integration

Conclusions

— Traditional testing approaches are no longer valid— Semantic Web technologies are needed:

Definition and customisation of rules and rulesets (tests and test suites)

Expression of results (EARL)

— Experts need to be incorporated into the workflow

«Expert Viewer» approach

— Web apps to be accessed via rendering engine or OS Accessibility API

Q & A