Tags: attribute

44

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Tuesday, December 27th, 2022

How We Verified Ourselves on Mastodon — and How You Can Too – The Markup

It gives me warm fuzzies to see an indie web building block like rel="me" getting coverage like this.

Sunday, October 30th, 2022

Overloading buttons

It’s been almost two years since I added audio playback on The Session. The interface is quite straightforward. For any tune setting, there’s a button that says “play audio”. When you press that button, audio plays and the button’s text changes to “pause audio.”

By updating the button’s text like this, I’m updating the button’s accessible name. In other situations, where the button text doesn’t change, you can indicate whether a button is active or not by toggling the aria-pressed attribute. I’ve been doing that on the “share” buttons that act as the interface for a progressive disclosure. The label on the button—“share”—doesn’t change when the button is pressed. For that kind of progressive disclosure pattern, the button also has an aria-controls and aria-expanded attribute.

From all the advice I’ve read about button states, you should either update the accessible name or change the aria-pressed attribute, but not both. That would lead to the confusing situation of having a button labelled “pause audio” as having a state of “pressed” when in fact the audio is playing.

That was all fine until I recently added some more functionality to The Session. As well as being able to play back audio, you can now adjust the tempo of the playback speed. The interface element for this is a slider, input type="range".

But this means that the “play audio” button now does two things. It plays the audio, but it also acts as a progressive disclosure control, revealing the tempo slider. The button is simultaneously a push button for playing and pausing music, and a toggle button for showing and hiding another interface element.

So should I be toggling the aria-pressed attribute now, even though the accessible name is changing? Or is it enough to have the relationship defined by aria-controls and the state defined by aria-expanded?

Based on past experience, my gut feeling is that I’m probably using too much ARIA. Maybe it’s an anti-pattern to use both aria-expanded and aria-pressed on a progressive disclosure control.

I’m kind of rubber-ducking here, and now that I’ve written down what I’m thinking, I’m pretty sure I’m going to remove the toggling of aria-pressed in any situation where I’m already toggling aria-expanded.

What I really need to do is enlist the help of actual screen reader users. There are a number of members of The Session who use screen readers. I should get in touch and see if the new functionality makes sense to them.

Thursday, September 8th, 2022

TIL: You Can Access A User’s Camera with Just HTML

The capture attribute is pretty nifty—and I just love that you get so much power in a declarative way:

<input type="file" accept="image/*" capture="environment">

Wednesday, November 17th, 2021

htmx - high power tools for html

I really like the progressive enhancement approach that this little library uses—it’s basically the Hijax approach I was talking about back in the days of Bulletproof Ajax but all wrapped up into a neat package that you can use entirely via HTML attributes.

Tuesday, March 16th, 2021

Wednesday, November 11th, 2020

Not so short note on aria-label usage – Big Table Edition – HTML Accessibility

This is a very handy table of elements from Steve of where aria-label can be applied.

Like, for example, not on a div element.

Tuesday, November 10th, 2020

aria-live

I wrote a little something recently about using ARIA attributes as selectors in CSS. For me, one of the advantages is that because ARIA attributes are generally added via JavaScript, the corresponding CSS rules won’t kick in if something goes wrong with the JavaScript:

Generally, ARIA attributes—like aria-hidden—are added by JavaScript at runtime (rather than being hard-coded in the HTML).

But there’s one instance where I actually put the ARIA attribute directly in the HTML that gets sent from the server: aria-live.

If you’re not familiar with it, aria-live is extremely useful if you’ve got any dynamic updates on your page—via Ajax, for example. Let’s say you’ve got a bit of your site where filtered results will show up. Slap an aria-live attribute on there with a value of “polite”:

<div aria-live="polite">
...dynamic content gets inserted here
</div>

You could instead provide a value of “assertive”, but you almost certainly don’t want to do that—it can be quite rude.

Anyway, on the face it, this looks like exactly the kind of ARIA attribute that should be added with JavaScript. After all, if there’s no JavaScript, there’ll be no dynamic updates.

But I picked up a handy lesson from Ire’s excellent post on using aria-live:

Assistive technology will initially scan the document for instances of the aria-live attribute and keep track of elements that include it. This means that, if we want to notify users of a change within an element, we need to include the attribute in the original markup.

Good to know!

Tuesday, October 27th, 2020

ARIA in CSS

Sara tweeted something recently that resonated with me:

Also, Pro Tip: Using ARIA attributes as CSS hooks ensures your component will only look (and/or function) properly if said attributes are used in the HTML, which, in turn, ensures that they will always be added (otherwise, the component will obv. be broken)

Yes! I didn’t mention it when I wrote about accessible interactions but this is my preferred way of hooking up CSS and JavaScript interactions. Here’s old Codepen where you can see it in action:

[aria-hidden='true'] {
  display: none;
}

In order for the functionality to work for everyone—screen reader users or not—I have to make sure that I’m toggling the value of aria-hidden in my JavaScript.

There’s another advantage to this technique. Generally, ARIA attributes—like aria-hidden—are added by JavaScript at runtime (rather than being hard-coded in the HTML). If something goes wrong with the JavaScript, the aria-hidden value isn’t set to “true”, which means that the CSS never kicks in. So the default state is for content to be displayed. There’s no assumption that the JavaScript has to work in order for the CSS to make sense.

It’s almost as though accessibility and progressive enhancement are connected somehow…

Thursday, October 1st, 2020

AddyOsmani.com - Preload late-discovered Hero images faster

Did you know there’s an imagesrcset attribute you can put on link rel="preload" as="image" (along with an imagesizes attribute)?

I didn’t. (Until Amber pointed this out.)

Tuesday, August 25th, 2020

The difference between aria-label and aria-labelledby - Tink - Léonie Watson

A handy reminder from Léonie (though remember that the best solution is to avoid the problem in the first place—if you avoid using ARIA, do that).

Monday, August 17th, 2020

Netlify redirects and downloads

Making the Clearleft podcast is a lot of fun. Making the website for the Clearleft podcast was also fun.

Design wise, it’s a riff on the main Clearleft site in terms of typography and general layout. On the development side, it was an opportunity to try out an exciting tech stack. The workflow goes something like this:

  • Open a text editor and type out HTML and CSS.

Comparing this to other workflows I’ve used in the past, this is definitely the most productive way of working. Some stats:

  • Time spent setting up build tools: 00:00
  • Time spent wrangling the pipeline to do exactly what you want: 00:00
  • Time spent trying to get the damn build tools to work again when you return to the project after leaving it alone for more than a few months: 00:00:00

I have some files. Some images, three font files, a few pages of HTML, one RSS feed, one style sheet, and one minimal service worker script. I don’t need a web server to do anything more than serve up those files. No need for any dynamic server-side processing.

I guess this is JAMstack. Though, given that the J stands for JavaScript, the A stands for APIs, and I’m not using either, technically it’s Mstack.

Netlify suits my hosting needs nicely. It also provides the added benefit that, should I need to update my CSS, I don’t need to add a query string or anything to the link elements in the HTML that point to the style sheet: Netlify does cache invalidation for you!

The mp3 files of the actual podcast episodes are stored on S3. I link to those mp3 files from enclosure elements in the RSS feed, which is what makes it a podcast. I also point to the mp3 files from audio elements on the individual episode pages—just above the transcript of each episode. Here’s the page for the most recent episode.

I also want people to be able to download the mp3 file directly if they want (or if they want to huffduff an episode). So I provide a link to the mp3 file with a good ol’-fashioned a element with an href attribute.

I throw in one more attribute on that link. The download attribute tells the browser that the URL in the href attribute should be downloaded instead of visited. If you give a value for the download attribute, it will over-ride the file name:

<a href="/files/ugly-file-name.xyz" download="nice-file-name.xyz">download</a>

Or you can use it as a Boolean attribute without any value if you’re happy with the file name:

<a href="/files/nice-file-name.xyz" download>download</a>

There’s one catch though. The download attribute only works for files on the same origin. That’s an issue for me. My site is podcast.clearleft.com but my audio files are hosted on clearleft-audio.s3.amazonaws.com—the download attribute will be ignored and the mp3 files will play in the browser instead of downloading.

Trys pointed me to the solution. It turns out that Netlify can do some server-side processing. It can do redirects.

I added a file called _redirects to the root of my project. It contains one line:

/download/*  https://clearleft-audio.s3.amazonaws.com/podcast/:splat  200

That says that any URLs beginning with /download/ should redirect to clearleft-audio.s3.amazonaws.com/podcast/. Everything after the closing slash is captured with that wild card asterisk. That’s then passed along to the redirect URL as :splat. That’s a new one on me. I hadn’t come across that terminology, but as someone who can never remember the syntax of regular expressions, it works for me.

Oh, and the 200at the end is the status code: okay.

Now I can use this /download/ path in my link:

<a href="/download/season01episode06.mp3" download>Download mp3</a>

Because this URL on the same origin, the download attribute works just fine.

Friday, June 12th, 2020

HTML Tutorial for Beginners 101 (Including HTML5 Tags) - WebsiteSetup

A really great one-page guide to HTML from Bruce. I like his performance-focused intro:

If your site is based on good HTML, it will load fast. Browsers incrementally render HTML—that is, they will display a partially downloaded web page to the user while the browser awaits the remaining files from the server.

Modern fashionable development techniques, such as React, require a lot of JavaScript to be sent to the user. When it’s all downloaded, the user’s device must parse and execute the JavaScript before it can even start to construct the page. On a slow network, or on a cheaper, low-powered device, this can result in an excruciatingly slow load and is a heavy drain on the battery.

Wednesday, June 10th, 2020

Optimizing keyboard navigation using tabindex and ARIA — Sara Soueidan

Smart thinking from Sara to improve usability for keyboard users by using aria-hidden="true" tabindex="-1" to skip duplicate links:

A good rule of thumb for similar cases is that if you have multiple consecutive links to the same page, there is probably a chance to improve keyboard navigation by skipping some of those links to reduce the number of tab stops to one. The less tab stops, the better, as long as it does not worsen or compromise on other aspects of usability.

I’ve cautiously implemented this pattern now over on The Session where snippets of comments had both a title link and a “more” link going to the same destination.

Friday, May 29th, 2020

A Guide to the Responsive Images Syntax in HTML | CSS-Tricks

Chris has put together one of his indispensable deep dives, this time into responsive images. I can see myself referring back to this when I need to be reminded of the syntax of srcset and sizes.

Monday, April 20th, 2020

Better Form Inputs for Better Mobile User Experiences | CSS-Tricks

Here’s one simple, practical way to make apps perform better on mobile devices: always configure HTML input fields with the correct type, inputmode, and autocomplete attributes. While these three attributes are often discussed in isolation, they make the most sense in the context of mobile user experience when you think of them as a team.

This is an excellent deep dive with great advice:

You may think that you are familiar with the basic autocomplete options, such as those that help the user fill in credit card numbers or address form fields, but I’d urge you to review them to make sure that you are aware of all of the options. The spec lists over 50 values!

Friday, April 3rd, 2020

Responsive Images the Simple Way - Cloud Four

A nice succint explanation of using the srcset and sizes attributes on the img element—remember, you probably don’t need picture and source elements if your use case is swapping out different sized versions of the same image.

One caveat thought: you do need to know the dimensions of the images. If you’re dealing with unknown or user-generated photos, that can be an issue.

Monday, March 23rd, 2020

Inclusive Inputs « Texte | ovl – code & design

This is a great walkthough of making a common form pattern accessible. No complex code here: some HTML is all that’s needed.

Friday, March 20th, 2020

What Does `playsinline` Mean in Web Video? | CSS-Tricks

I have to admit, I don’t think I even knew of the existence of the playsinline attribute on the video element. Here, Chris runs through all the attributes you can put in there.

Friday, February 28th, 2020

Why the GOV.UK Design System team changed the input type for numbers - Technology in government

Some solid research here. Turns out that using input type=”text” inputmode=”numeric” pattern="[0-9]*" is probably a better bet than using input type="number".

Friday, February 14th, 2020

A Complete Guide to Links and Buttons | CSS-Tricks

Chris takes two side-by-side deep dives; one into the a element, the other into the button element.

Even if you think you already know those elements well, I bet there’ll be something new here for you. Like, did you know that the button element can have form over-riding attributes like formaction, formenctype, formmethod, formnovalidate, and formtarget?