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Seven Steps to a More Accessible Website. Todd Weissenberger Web Accessibility Coordinator University of Iowa. Training Objectives. Gain a fundamental understanding of web accessibility and its role in site design at Iowa
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Seven Steps to a More Accessible Website Todd Weissenberger Web Accessibility Coordinator University of Iowa
Training Objectives • Gain a fundamental understanding of web accessibility and its role in site design at Iowa • Understand how to obtain and use a selection of tools to evaluate the accessibility of your site • Experience a variety of techniques intended to improve overall web accessibility
Getting Started • Download files from http://myweb.uiowa.edu/tmweiss/7/ • Scenario pages • Utilities • Bookmark this page for plug-in installation • Locate Adobe Dreamweaver CS5 • Web editor
Web Accessibility Project Status Report • Policy pending ratification • WCAG 2.0, Level AA Compliance indicated by policy • Units should now: • Build new web content with accessibility in mind • Develop accessibility assessment and remediation strategy • Request initial evaluation from Web Accessibility Coordinator
WCAG 2.0, Level AA Accessibility Guidelines • Worldwide standard since December, 2008 • Adopted or under consideration by all CIC institutions, and numerous other entities • Twelve basic guidelines governing accessible HTML, scripting, media and other web content • http://www.w3.org/TR/WCAG20/
Perceivable • 1.1 Text Alternatives: Provide text alternatives for any non-text content so that it can be changed into other forms people need, such as large print, braille, speech, symbols or simpler language. • 1.2 Time-based Media: Provide alternatives for time-based media. • 1.3 Adaptable: Create content that can be presented in different ways (for example simpler layout) without losing information or structure. • 1.4 Distinguishable: Make it easier for users to see and hear content including separating foreground from background.
Operable • 2.1 Keyboard Accessible: Make all functionality available from a keyboard. • 2.2 Enough Time: Provide users enough time to read and use content. • 2.3 Seizures: Do not design content in a way that is known to cause seizures. • 2.4 Navigable: Provide ways to help users navigate, find content, and determine where they are.
Understandable • 3.1 Readable: Make text content readable and understandable. • 3.2 Predictable: Make Web pages appear and operate in predictable ways. • 3.3 Input Assistance: Help users avoid and correct mistakes.
Robust • 4.1 Compatible: Maximize compatibility with current and future user agents, including assistive technologies.
Techniques • W3 specifies two categories of techniques • Sufficient Techniques • Advisory Techniques • http://www.w3.org/TR/2010/NOTE-WCAG20-TECHS-20101014/intro.html
July 1, 2011 – December 31, 2011 Site Assessment
Site Assessments • Self-Assessment • Performed by site managers prior to initial Web Accessibility Evaluation • Addresses “low-hanging fruit” and common compliance flags • Likely to catch numerous occurrences of non-conforming code • Site assessment by ITS Web Accessibility Coordinator • Automated evaluation tool • Recommendations and best practices • Assistance with remediation/rebuilding
Common Compliance Issues* • Missing or inadequate text equivalents • Insufficient color contrast • Missing LANG attribute • Non-adaptive font size • Nested headings • <table> construction • <form> elements
Evaluation and Assessment Tools • A-Checker [achecker.ca] (free) • Functional Accessibility Evaluator [fae.cita.uiuc.edu] (free)1 • WAVE [http://wave.webaim.org] (free) • Juicy Studio [juicystudio.com] • Web Developer Toolbar • AIS Toolbar for IE [visionaustralia.org.au] (free) • Colour Contrast Analyser [visionaustralia.org.au] (free)2 • Complex Table Checker [visionaustralia.org.au] (free)3 The FAE also comes as a Firefox toolbar, and is compatible through Firefox version 4 Available as a stand-alone .exe Complex Table Checker is a Firefox add-on, compatible through Firefox version 4
HiSoftware Compliance Sheriff • HiSoftware Compliance Sheriff • Adopted by the University of Iowa • Licensed to Web Accessibility Project to perform automated site testing • Analyzes multiple navigation levels • Customizable checkpoints • Yields a variety of results and reports • Maps occurrences to WCAG 2.0 checkpoints • Results can be updated manually
Guideline 1.1 Provide text alternatives for any non-text content so that it can be changed into other forms people need, such as large print, braille, speech, symbols or simpler language. Text Alternatives
WCAG Techniques (Selected) GENERAL • G94: Providing short text alternative • G95: Providing short text alternatives that provide a brief description of the non-text content AND • G92: Providing long description for non-text content that serves the same purpose and presents the same information using a long text alternative technique listed below • G74: Providing a long description in text near the non-text content, with a reference to the location of the long description in the short description • G73: Providing a long description in another location with a link to it that is immediately adjacent to the non-text content • G82: Providing a text alternative that identifies the purpose of the non-text content • G100: Providing the accepted name or a descriptive name of the non-text content using a short text alternative technique HTML • H67: Using null alt text and no title attribute on img elements for images that AT should ignore • H2: Combining adjacent image and text links for the same resource • H37: Using alt attributes on imgelements • H24: Providing text alternatives for the area elements of image maps • H30: Providing link text that describes the purpose of a link for anchor elements • H45: Using longdesc
Practices to Avoid: • Using a filename or path as ALT text • Redundant ALT text: when descriptive text exists adjacent to a non-text element, use an empty ALT attribute • Placing important information in background images
Non-compliant text alternatives • Placeholder text • alt=“spacer” • alt=“image1” • Text content that does not convey the meaning of the non-text content • alt=“Site Introduction” • Filenames • DSC1991.jpg • 20110411.png
Describing Non-Text Content • Short description (can provide the same information and function as non-text) • Long description is necessary to provide same information and function as non-text) • Adjacent to non-text content • Linkable from non-text content • Reference via LONGDESC (deprecated in HTML 5)
ALT Text: Short Description • ALT • May be sufficient by itself for static images • Should contain information that provides same information and function
G95: Short Text Description <imgsrc=“wheelchairBBall.png"alt="Detail of WheelchairBasketball Game" />
G94: Short Description, Same Purpose and Information <imgsrc="braille.png" alt=“Diagram of Braille letter W, a single raised dot in the center left position and raised dots in the top, middle and bottom right positions." />
Long Description • Actually two descriptions • A short description that describes the image in brief • A long description that conveys the information contained in the image • Long description can include: • Descriptive content immediately adjacent to the image (G73) • A link or reference to descriptive content in another location (G74) • Use of the LONGDESC attribute to identify the URI of a long description of the non-text element
G74: Long and Short Descriptions <imgsrc="q1_chart.png“alt="Q1 Regional Sales Chart. Details follow the chart" /> <p>The preceding chart describes first quarter sales for...</p>
G73: Link Adjacent to Description <imgsrc="q1_chart.png" alt="First Quarter Sales Chart, 2010" /> <a href="q1_chart.html">View a complete description here</a>
H2: Adjacent Image and Text Links • When a graphical element acts as a link and is adjacent to a text link to the same resource, the two items should be combined • The repetition of the links may cause confusion or disorientation among some users
Adjacent Image and Text Links <a href="http://www.chicagoreader.com"><img src="common/images/chi.jpg“alt="LearnMore About Chicago" /></a> <a href="http://www.chicagoreader.com">Learn More About Chicago</a>
Adjacent Image and Text Links <a href="http://www.chicagoreader.com"><img src="common/images/chi.jpg" alt="" />Go to the Chicago page</a>
Create content that can be presented in different ways (for example simpler layout) without losing information or structure. Guideline 1.3
1.3.1 Info and Relationships: Information, structure, and relationships conveyed through presentation can be programmatically determined or are available in text. (Level A) Use h1-h6 to identify headings
Make it easier for users to see and hear content including separating foreground from background. Guideline 1.4
SC 1.4.3: The visual presentation of text and images of text has a contrast ratio of at least 4.5:1 Color Contrast