Building a better, accessible web

About Me

Matt Stow

@stowball
 

Senior UX Engineer at
National Rugby League

“We should be able to access the web … regardless of the software we use, the computer we have, the language we speak … and regardless of our sensory or interaction modes”

Disability statistics

  • More than 1 billion (15%) of the world‘s population has some form of substantial or long-term disability
     
  • Over 50% find browsing the web to be challenging
     
  • 30 – 50% of people aged 65+ have a disability
     
  • Disability rates are continuing to rise as populations age

‘People with disability’ is the only minority group that anyone can join at any time”

#PlotTwist

Equal access is often  required by law

  • Australia
    All websites should comply with WCAG 2.0 to a minimum of AA-Level
     
  • USA
    All Federal websites must provide comparable access for people with disabilities
     
  • European Union
    Public sector websites to be accessible by 2018 by making them WCAG compliant

Types of disabilities

  • Hearing impairments
     
  • Cognitive & learning disabilities
     
  • Mobility & physical impairments
     
  • Vision disabilities

Hearing impairments

  • Provide captions and/or transcripts for audio and video
  • Non-native speakers also benefit

Who’s affected?

People with full or partial hearing loss

Quick wins

Cognitive & learning disabilities

  • Avoid justified text and ALL CAPS; use sans-serif fonts
  • Simplify the language used and reduce the amount of text
  • Reduce the complexity of the UI’s appearance and functions
  • Use Invisible Animation and Context-Shifting UX

Who’s affected?

People with ADD, autism, dementia, dyslexia and more

Quick wins

Mobility & physical impairments

  • Mouse hover actions need to be forgiving
  • Ensure a sensible tabbing order
  • Visible focus states for all interactive elements

Who’s affected?

People with limited dexterity or upper limb disabilities

Quick wins

Vision disabilities

  • People with colour blindness
  • People with low or no vision

Who’s affected?

  • Ensure text alternatives for images & visually absent text
  • Ensure your palette has a suitable colour contrast ratio

Quick wins

Colour blindness

  • Deuteranopia (red-green)
  • Protanopia (another red-green)
  • Tritanopia (blue-yellow)
  • Up to 10% of the population may be affected

You can’t rely on colour alone to convey information

(red-green)

(another red-green)

(blue-yellow)

Simulating Deuteranopia

Simulating Protanopia

Trello Labels have a color blind friendly mode!

Simulating colour blindness

All have slightly different features and results, and are useful at different times in the process

Colour contrast ratio

  • Text ratio needs to be 3 – 4.5:1 depending on size
  • But don't make the ratio too high!
  • Test with aremycolorsaccessible.com

Tools used by the vision impaired

  • Screen magnifiers and browser zoom
  1. Windows
  2. MacOS and iOS
  3. Chrome on desktop
  4. Android

Screen reader statistics

  • 85% of users primarily use Windows
  • 49% of those use screen readers with IE
  • 69% use screen readers on mobile
  • 70% of those use iOS as their mobile platform

Screen reader features

  • Quick access to landmarks, headings, lists and links
  • Shortcuts for navigating to, and using form controls
  • Connect to Braille displays
  • and a lot more…

I highly recommend doing the VoiceOver Training course that's built in to macOS to learn more

How to build for #a11y

  1. Follow the Web Content Accessibility Guidelines (WCAG)
     
  2. Use semantic HTML (and understand the impact of CSS)
     
  3. Implement WAI-ARIA (often with JavaScript)

#

Mattstow’s hierarchy of #a11y*

* Terrible pun

What is WCAG 2.0?

  • A W3C standard which recommends how to make web content more accessible to people with disabilities
  • It's generic, so doesn‘t dictate technology choices
  • Divided in to 12 major guidelines across 4 core principles
  • Each sub-guideline has a conformance rating from A–AAA

WCAG at a glance

  • Provide text alternatives for non-text content
  • Provide captions/alternatives for multimedia

Principle 1: Perceivable

  • Create content that can be presented in different ways without losing meaning
  • Make it easier for users to see and hear content

WCAG at a glance

  • Make all functionality available from a keyboard
  • Give users enough time to read and use content
  • Do not use content that causes seizures
  • Help users navigate and find content

Principle 2: Operable

WCAG at a glance

  • Make text readable and understandable
  • Make content appear and operate in predictable ways
  • Help users avoid and correct mistakes

Principle 3: Understandable

WCAG at a glance

  • Maximise compatibility with current and future user agents

Principle 4: Robust

Use semantic HTML

  • Add a valid and relevant `lang` attribute to <html>
  • Don‘t disable zooming
  • Use appropriate HTML5 elements
  • Don‘t skip heading levels
  • Use native browser controls where possible
  • Only <a> and <button> should be “clickable”
  • All form elements must be labelled
  • Placeholders aren‘t labels

Understand the impact of CSS

  • Test without CSS to ensure a logical source order
  • Minimum of 14px font size for body content
  • Pseudo content is read out, so it has to be meaningful
  • OK to use a .visually-hidden utility class to hide content
  • Don‘t remove `:focus` outlines – or provide alternatives
  • `visibility: hidden` hides from ATs but is animatable!

Smart :focus styles

function keyboardFocus (e) {
    if (e.keyCode !== 9) {
        return;
    }
    
    document.documentElement.classList.add('keyboard-focus');
    document.removeEventListener('keydown', keyboardFocus, false);
}

document.addEventListener('keydown', keyboardFocus, false);
:focus {
    box-shadow: none;
    outline: none;
}

.no-js :focus, .keyboard-focus .element:focus {
    box-shadow: 0 0 2px 1px #00cdcb;
}

Future smart :focus styles!

:focus {
    box-shadow: none;
    outline: none;
}

.element:focus-ring {
    box-shadow: 0 0 2px 1px #00cdcb;
}

Animating visibility: hidden


.chip.is-hidden {
    max-width: 0;
    opacity: 0;
    transform: scale(0);
    transition: opacity ease 0.25s,
                transform ease 0.25s,
                margin ease 0.45s 0.15s,
                max-width ease 0.45s 0.15s,
                visibility 0s 0.6s;
    visibility: hidden;
}

What is WAI-ARIA?

  • A spec on how to increase the accessibility of
    Rich Internet Applications
  • Uses role attributes to describe the type of element
  • Uses property attributes to describe relationships, functions and UI states

Common ARIA roles

  • banner
  • complementary
  • contentinfo
  • main
  • navigation
  • search

Landmarks

  • alert
  • dialog
  • tab
  • tablist
  • tabpanel
  • tooltip

Widgets

Common ARIA properties

  • aria-current (state)
  • aria-expanded (state)
  • aria-haspopup
  • aria-hidden (state)
  • aria-invalid (state)
  • aria-label
  • aria-pressed (state)
  • aria-selected (state)

Widgets

  • aria-atomic
  • aria-controls
  • aria-labelledby
  • aria-live
  • aria-owns

Others

Useful examples!

Hamburger menu

<nav role="navigation" aria-label="Main">
    <button aria-label="Navigation" aria-controls="menu"
     aria-haspopup="true" aria-expanded="false"
     >🍔</button>

    <ul id="menu">
        <li><a href="#">Home</a></li>
        <li><a href="#">About</a></li>
    </ul>
</nav>
var $button = $('button');
var isMenuOpen = false;

$button.on('click', function () {
    isMenuOpen = !isMenuOpen;
    
    $button.attr('aria-expanded', isMenuOpen);
});
button[aria-expanded="true"] {
    /* change caret indicator */
}

button[aria-expanded="true"] + #menu {
    /* show menu */
}

Accessible hamburger menu

Add to cart

<div class="product">
    <!-- This should be in a form with a server-side fallback -->
    <h3>Super Mario T-shirt</h3>
    <button class="btn btn-default">
        Add <span class="u-visually-hidden">Super Mario T-shirt</span> to cart
    </button>
</div>

<div id="toaster" role="alert" aria-atomic="true" aria-live="assertive"></div>
var $button = $('button');
var $toaster = $('#toaster');

$button.on('click', function () {
    $toaster
        .html('<span class="u-visually-hidden">Super Mario T-shirt has been </span>' +
        'Added to your cart').addClass('is-visible');
    setTimeout(function () {
       $toaster.removeClass('is-visible'); 
    }, 1500);
});
.u-visually-hidden {
    /* https://gist.github.com/stowball/2704364c1ceefb1d7eaf570b903463b3 */
}

Accessible add to cart

Implementation resources

Inclusive design benefits everyone

#a11y isn’t that hard

Practice makes perfect

Thank you!

@stowball
 

 

Building a better, accessible web

By Matt Stow

Building a better, accessible web

Detailing why accessibility matters, the types of disabilities there are/how to cater for them, and how to write good, semantic HTML and utilise ARIA to create accessible, robust web applications

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