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Fringe Accessibility Techniques(That Probably Shouldn’t Be)
Presented by Adrian Roselli for Guelph Accessibility Conference
About Adrian Roselli
• Co-written four books.• Technical editor
for two books.• Written over fifty
articles, most recentlyfor .net Magazine andWeb Standards Sherpa.
Great bedtime reading!
About Adrian Roselli
• Member of W3C HTML Working Group*, W3C Accessibility Task Force, five W3C Community Groups.
• Building for the web since 1993.• Business owner / founder, ~20 years.• Now independent / at The Paciello Group.• Learn more at AdrianRoselli.com.• Avoid on Twitter @aardrian.
I warned you.
What is a11y?
• A numeronym for “accessibility”:• The first and last letter (accessibility),• The number of characters omitted (a11y).
• Prominent on Twitter (character restrictions):• #a11y
• Examples:• l10n → localization• i18n → internationalization
Ain’t language funsies?
What We’ll Cover
• Common(?) Techniques• The (not really) Fringe• Key Takeaways
Work with me, people.
Common(?) Techniques
1 of 3 sections.
Common(?) Techniques
• Click on field labels
Make sure the corresponding field gets focus.
Common(?) Techniques
• Click on field labels• Unplug your mouse
Make sure you can still use the page / application.
Common(?) Techniques
• Click on field labels• Unplug your mouse• Turn off images
Make sure no important content has disappeared.
Common(?) Techniques
• Click on field labels• Unplug your mouse• Turn off images• Turn off CSS
Make sure the page still makes sense.
Common(?) Techniques
• Click on field labels• Unplug your mouse• Turn off images• Turn off CSS• Check color contrast
Make sure it’s sufficient.
Common(?) Techniques
• Click on field labels• Unplug your mouse• Turn off images• Turn off CSS• Check color contrast• Consider hyperlink text
Be consistent and clear, managing expectations the whole time.
The (not really) Fringe
2 of 3 sections.
Use Link Underlines
http://www.theverge.com/2014/3/13/5503894/google-removes-underlined-links-site-redesign
Use Link Underlines
• You are not Google:• Users know Google’s layout,• Users probably don’t visit your site daily.
• Relying on color alone will not suffice (WCAG 1.4.1 [A], 1.4.3 [AA]),
• Necessary contrast values:• 4.5:1 between text and its background for copy,• 3:1 between text and its background for larger text,• 3:1 between surrounding text and a hyperlink, plus an
additional visual cue (G183).http://adrianroselli.com/2014/03/i-dont-care-what-google-did-just-keep.html
Use :focus Styles
• Particularly if you removed link underlines,• Everywhere you have :hover, add :focus,• Look for :focus{outline:none;} in libraries:• If you find it, remove it.
• Easy to test with the tab key.
http://adrianroselli.com/2014/06/keep-focus-outline.html
Use <h#> Wisely
Use <h#> Wisely
• Use only one <h1> per page,• Don’t skip heading levels,• Use appropriate nesting,• There is no Document Outline Algorithm:• Don’t use <h1> within every new <section> nor <article>,
• This will not affect your SEO.
http://adrianroselli.com/2013/12/the-truth-about-truth-about-multiple-h1.html
Use Only One <main> per Page
Modified version of Hixie’s image at https://github.com/whatwg/html/issues/100#issuecomment-138620240
Use Only One <main> per Page
• <main> maps directly to role="main",• AT users expect one main content block, may
miss subsequent <main>s,• AT doesn’t expose that there are multiples,• Can erode trust in landmark navigation.
http://adrianroselli.com/2015/09/use-only-one-main-on-a-page.html
Source Order Matters
http://codepen.io/aardrian/full/MavVeb/
Firefox
Chrome
Source Order Matters
• CSS techniques allow visual order to break from DOM order:• Floats,• Absolute positioning,• Flexbox (see 5.4.1 of ED for a11y note),• Grid (read Rachel Andrew on subgrid).
• WCAG 1.3.2 and 2.4.3 describe meaningful sequence and tab order matching visual flow,
• Different behavior among different browsers.http://adrianroselli.com/2015/09/source-order-matters.html http://200ok.nl/a11y-flexbox/
Don’t Use tabindex > 0
https://www.digitalgov.gov/2014/11/17/user-experience-impossible-the-line-between-accessibility-and-usability/
Don’t Use tabindex > 0
• tabindex="-1"• Use to set focus with script,• Does not put it in tab order of page.
• tabindex="0"• Allows user to set focus (eg: via keyboard),• Puts in tab order of page (based on DOM).
• tabindex="1" (or greater)• Do not do this,• Messes with natural tab order.
http://adrianroselli.com/2014/11/dont-use-tabindex-greater-than-0.html
Maybe Use tabindex=0
http://adrianroselli.com/2016/02/keyboard-and-overflow.html
Maybe Use tabindex=0
• Do you have scrolling content boxes?• Keyboard users probably cannot access it.
• Do you have content that expands on hover?• Keyboard users probably cannot access it.
• A technique:• <div role="region" aria-label="[if appropriate]" tabindex="0">
http://adrianroselli.com/2016/02/keyboard-and-overflow.html
<button>, <input>, or <a>
http://adrianroselli.com/2016/01/links-buttons-submits-and-divs-oh-hell.html
<button>, <input>, or <a>
http://adrianroselli.com/2016/01/links-buttons-submits-and-divs-oh-hell.html
<button>, <input>, or <a>
• Don’t use a <div> nor <span>.• Does the control take me to another URL?• Use an <a href>.• Note: does not fire on space-bar.
• Does the control change something on the current page?• Use a <button>.
• Does the control submit form fields?• Use a <input type="submit"> or <button type="submit">.
http://adrianroselli.com/2016/01/links-buttons-submits-and-divs-oh-hell.html
Set lang attribute on <html>
http://codepen.io/aardrian/pen/rOGYNL
Set lang attribute on <html>
http://codepen.io/aardrian/pen/rOGYNL
Set lang attribute on <html>
• VoiceOver uses to auto-switch voices,• VoiceOver uses appropriate accenting,• JAWS loads correct phonetic engine /
phonologic dictionary,• NVDA matches VoiceOver and JAWS,• Use the correct lang value:• Sub-tags are ok,• Avoid private-use: en-GB-x-hixie
http://adrianroselli.com/2015/01/on-use-of-lang-attribute.html
Don’t Disable Zoom
http://codepen.io/aardrian/full/dYNJOVhttp://codepen.io/aardrian/full/ojBpjw
Don’t Disable Zoom
• Allow users on mobile to zoom in,• Look in <meta name="viewport"> for this:
• minimum-scale=1.0• maximum-scale=1.0• user-scalable=no
• Look in @-ms-viewport {} for this:• zoom:1.0
• Grab your boss/client, shout “Enhance!”• (Google AMP HTML is getting fixed)
http://adrianroselli.com/2015/10/dont-disable-zoom.html
Use Captions/Subtitles
https://www.youtube.com/watch?v=V592VMJeXc8
https://www.youtube.com/watch?v=zCqN_cCLnnk
Use Captions/Subtitles
Use Captions/Subtitles
• Everybody uses them:• Working in public, in bed, at home,• Surfing in public, in bed, at work.
• Should include audio descriptions,• Should include speaker identification,• Review auto-captions (“craptions”):• NoMoreCraptions.com
http://adrianroselli.com/2013/11/captions-in-everyday-use.html
Use Captions/Subtitles
• Do video/audio clips have text alternatives?• Are links to closed-captions or transcripts built into
the player or separate text links?• Is there an audio description available?• Tools:• Media Access Australia YouTube captioning tutorial,
Vimeo captioning tutorial,• Tiffany Brown’s WebVTT tutorial,• DIY Resources for Closed Captioning and Transcription
from 3 Play Media.http://webaim.org/techniques/captions/
Test in Windows High Contrast Mode
http://buffalosoccerclub.org/About
Test in Windows High Contrast Mode
• It removes CSS background images,• This is changing in Edge,
• Colors defined in your CSS are overridden,• To activate:• Left ALT + left SHIFT + PRINT SCREEN
• Media queries:• -ms-high-contrast: active• -ms-high-contrast: black-on-white• -ms-high-contrast: white-on-black
http://adrianroselli.com/2012/08/css-background-images-high-contrast-mode.html
Avoid Infinite Scroll
http://www.pewresearch.org/category/publications/
Avoid Infinite Scroll
• Makes it impossible to access some content:• Footer,• Sidebar links.
• Destroys the back button,• Makes it impossible to share a URL to specific
“page” of results,• Makes it impossible to jump ahead several “pages”
of results,• Can overwhelm AT users, less powerful devices.
http://adrianroselli.com/2014/05/so-you-think-you-built-good-infinite.htmlhttp://adrianroselli.com/2015/05/for-infinite-scroll-bounce-rate-is.html
Reconsider Typefaces for Dyslexia
• Use good typography rules:• Avoid justified text,• Use generous line spacing / leading,• Use generous letter spacing,• Avoid italics,• Generally use sans serif faces,• Use larger text,• Use good contrast,• Use clear, concise writing.
http://adrianroselli.com/2015/03/typefaces-for-dyslexia.html
Use On-Page Descriptions
http://adrianroselli.com/2014/04/we-need-to-raise-stink-about-net.html
Use On-Page Descriptions
• Not just for longdesc or aria-describedat, but any long description technique,
• Use an in-page anchor,• Don’t link to another page without reason:• Consider burden of loading a new page,• Consider burden of re-loading original page.
• Based on results of latest WebAIM screen reader survey results.
http://adrianroselli.com/2015/09/use-on-page-image-descriptions.html
role="search" on <form> is OK
http://codepen.io/aardrian/pen/MaKbPa/
role="search" on <form> is OK
• Now OK to use <form role="search">,• Walking back my own prior statements,• (think of this as a retraction)
• Nu Html Checker is already updated.
http://adrianroselli.com/2015/08/where-to-put-your-search-role.html#changed
Try Not to Tweet Pictures of Text
https://twitter.com/jmspool/status/546303256990076929https://twitter.com/lukew/status/541986091960528896 https://twitter.com/altonbrown/status/653030164985708544
Try Not to Tweet Pictures of Text
https://twitter.com/aardrian/status/733023365729005568
Try Not to Tweet Pictures of Text
• Twitter has finally added alternative text,• Must be using iOS/Android app, some third-party
apps (Easy Chirp),• Alternative text not exposed via web, not in
Twitter back-ups (yet),• Maybe also make your own:• Reply to own tweet with alt text,• Link to a tweet and provide alt text,• Link to long-form alternative text.
http://adrianroselli.com/2016/03/twitter-has-alt-text-with-some-caveats.html
Share a11y Experiences
http://blog.podio.com/2015/07/08/hard-truths-helped-us-start-improving-podio-experience-visually-impaired/https://medium.com/medium-eng/five-goofy-things-medium-did-that-break-accessibility-3bc804ae818d
Share a11y Experiences
• We’re all trying to do what we can,• Don’t attack those who doesn’t know what they
don’t know,• Someone may find something you never
considered,• You may get feedback on something you never
considered,• a11ywins.tumblr.com FTW:• Thanks to Marcy Sutton.
http://adrianroselli.com/2015/07/lets-share-more-accessibility-experiences.html
Key Takeaways
3 of 3 sections.
≠ Checklist
• Accessibility is not a checklist.
No matter how pretty that checklist looks now how many items you get to check.
Stairamp
Dean Bouchard on Flickrhttp://incl.ca/the-problems-with-ramps-blended-into-stairs/
= Process
• Accessibility is not a checklist.• Accessibility is an ongoing process.
You know, kinda like all software.
Snowtreeramp
Nicolas Steenhouthttps://twitter.com/vavroom/status/571092086365261824
“Wheelchair ramp at pharmacy not only hasn’t been cleared of snow but has 2 potted trees to ensure nobody can pass.”
Oslo Davis, https://twitter.com/oslodavis/status/373219062697840640
Fringe Accessibility Techniques(That Probably Shouldn’t Be)
Presented by Adrian Roselli for Guelph Accessibility Conference
Slides from this talk will be available at rosel.li/Guelph
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