RedwoodJS

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# Accessibility (aka a11y)

We built Redwood to make building websites more accessible (we write all the config so you don't have to), but Redwood's also built to help you make more accessible websites. Accessibility shouldn't be a nice-to-have. It should be a given from the start, a core feature that's built-in and well-supported.

There's a lot of great tooling out there that'll not only help you build accessible websites, but also help you learn exactly what that means.

With all this tooling, do I still have to manually test my application?

Unequivocally, yes. Even with all the tooling in the world, manual testing's still important, especially for accessibility. The GDS Accessibility team found that automated testing only catches ~30% of all the issues.

But just because the tools don't catch 'em all doesn't mean they're not valuable. It'd be much harder to learn what to look for without them.

# Accessible Routing with Redwood Router

For single-page applications (SPAs), accessibility starts with the Router. Without a full-page refresh, you just can't be sure that things like announcements and focus are being taken care of the way they're supposed to be. Here's a great example of how disorienting SPAs can be to screen-reader users. On navigation, nothing's announced. It's important not to understate the severity of this; the lack of an announcement isn't just buggy behavior, it's broken.

Normally the onus would be on you as a developer to announce to screen-reader users that they've navigated somewhere new. That's a lot to ask, and hard to get right, especially when you're just trying to build your app. Luckily, if you're writing good content and marking it up semantically, there's nothing you have to do! Redwood automatically and always announces pages on navigation. Redwood looks for announcements in this order:

  1. RouteAnnouncement
  2. h1
  3. document.title
  4. location.pathname

The reason for this is that announcements should be as specific as possible; more specific usually means more descriptive, and more descriptive usually means that users can not only orient themselves and navigate through the content, but also find it again. If you're not sure if your content is descriptive enough, see the W3 guidelines.

Even though Redwood looks for a RouteAnnouncement first, you don't have to have one on every page—it's more than ok for the h1 to be what's announced. RouteAnnouncement is there for when the situation calls for a custom announcement.

The API is simple: RouteAnnouncement's children will be announced; note that this can be something on the page, or can be visually hidden using the visuallyHidden prop:

// web/src/pages/HomePage.js

import { RouteAnnouncement } from '@redwoodjs/router'

const HomePage = () => {
  return (
    // this will still be visible
    <RouteAnnouncement>
      <h1>Welcome to my site!</h1>
    <RouteAnnouncement>
  )
}

export default HomePage 
// web/src/pages/AboutPage.js

import { RouteAnnouncement } from '@redwoodjs/router'

const AboutPage = () => {
  return (
    <h1>Welcome to my site!</h1>
    // this won't be visible
    <RouteAnnouncement visuallyHidden>
      All about me
    <RouteAnnouncement>
  )
}

export default AboutPage 

Whenever possible, it's good to maintain parity between the visual and audible experience of your app. That's just to say that visuallyHidden shouldn't be the first thing you reach for. But it's there if you need it!

# Focus

On page change, Redwood Router resets focus to the top of the DOM so that users can navigate through the new page. While this is the expected behavior (and the behavior you usually want), for some apps, especially those with a lot of navigation, it can be cumbersome for users to have tab through all that nav before getting to the main point. (And that goes for every page change!)

Right now, there's two ways to alleviate this in Redwood: with skip links and/or the RouteFocus component.

Since the main content isn't usually the first thing on the page, it's a good practice to provide a shortcut for keyboard and screen-reader users to skip to it. Skip links do just that, and if you generate a layout (yarn rw g layout) with the --skipLink flag, you'll get a layout with a skip link:

yarn rw g layout main --skipLink
import { SkipNavLink, SkipNavContent } from '@redwoodjs/router'
import '@reach/skip-nav/styles.css'

const MainLayout = ({ children }) => {
  return (
    <>
      <SkipNavLink />
      <nav></nav>
      <SkipNavContent />
      <main>{children}</main>
    </>
  )
}

export default MainLayout

SkipNavLink renders a link that remains hidden till focused; SkipNavContent renders a div as the target for the link. For more on these components, see the Reach UI docs.

Making sure your navs have skip links is a great practice that goes a long way. And it really doesn't cost you much! One thing you'll probably want to do is change the URL the skip link sends the user to when activated. You can do that by changing the contentId and id props of SkipNavLink and SkipNavContent respectively:

<SkipNavLink contentId="main-content" />

// ...

<SkipNavContent id="main-content" />

If you'd prefer to implement your own skip link, Ben Myers' blog is a great resource, and a great place to read about accessibility in general.

# RouteFocus

Sometimes you don't want to just skip the nav, but send a user somewhere. In this situation, you of course have the foresight that that place is where the user wants to be! So please use this at your discretion—sending a user to an unexpected location can be worse than sending them back the top.

Having said that, if you know that on a particular page change a user's focus is better off being directed to a particular element, the RouteFocus component is what you want:

import { RouteFocus } from '@redwoodjs/router'

const ContactPage = () => (
  <nav>
    {/* way too much nav... */}
  </nav>

  // the contact form the user actually wants to interact with 
  <RouteFocus>
    <TextField name="name" />
  </RouteFocus>
)

export default ContactPage

RouteFocus tells the router to send focus to it's child on page change. In the example above, when the user navigates to the contact page, the name text field on the form gets focus—the first field of the form they're here to fill out.

For a video example of using RouteFocus, see our meetup on Redwood's accessibility features.