How to implement ARIA on a responsive site - responsive-design

Question

We are working to make one of our responsive sites more accessible, but are struggling to get our heads around ARIA as it seems to go against the core principle of separating design elements from the HTML.
For example if an element is hidden in aria one would indicate it as aria-hidden="true". However most visibility is determined by media queries depending on screen size etc.
In other cases elements work completely different based on media queries. So at some sizes aria-haspopup="true" would be appropriate while on other resolutions the navigation is always visible.
Am I missing something, or are we at font tags all over again with this standard? Are we supposed to add / remove aria tags using javascript as appropriate?

Answer 1

Actually Kenneth, your question makes a lot of sense, and, yes - tooling for responsive sites is not ideal. I don't have an answer for you, but what I have to say is too long to be a comment...
Consider the following example:
You app has a menu button that opens a side drawer using a short sliding animation. Without a11y considerations, your job is easy (lets assume the drawer is on the left and has a width of 250px):
#media ... (min-width: 1000px)
#drawer {
left: 0;
}
#media ... (max-width: 999px)
#drawer {
left: -250px;
}
#drawer.opened {
left: 0;
}
(Not an exact syntax, add your own wizardy for the sliding animation)
To make this accessible, you'd have to do one of the following:
option 1
Don't use aria-hidden='true'. It's generally enough to hide the drawer using visibility:hidden or display:none. Of course, now you need to wait for the end of the sliding out animation to hide the drawer (or you
lose the animation).
option 2
Use aria-hidden='true'. You'll have to catch window resize and add / remove aria-hidden='true' when switching sizes (you lose the media query magic).
To sum things up, you're right. There's definitely room for improvement. This is especially true, considering the general shift to move stuff off of JS to keep things 60fps smooth.

Answer 2

You have to use the window.matchMedia function
For instance:
var mm = window.matchMedia("(min-width: 600px)");
mm.addListener(updateAriaHidden);
updateAriaHidden(mm);
var updateAriaHidden= function (obj) {
if (obj.matches) {
// set aria-hidden true/false when width >= 600px
}
else {
// set aria-hidden true/false when width < 600px
}
}
Using jQuery for instance, you can use the :hidden selector with a custom CSS class to set the aria-hidden attribute dynamically:
$(".toggleable:hidden').attr('aria-hidden', true);
$(".toggleable:visible').attr('aria-hidden', false);
The use of the custom class make it easy to match the elements which would change based on your media queries