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Re: Insertion of content into documents.

for

From: Mallory
Date: Jan 7, 2020 4:04AM

>- Assistive Technology being aware of the DOM being updated. This event change would need to be sent from the browser. Not sure if this occurs.

Not on its own.
Also, were this to be the case, most news pages would be unusable. Ah, who am I kidding? They currently are often unusable, due to the various chonky 3rd-party ads that take forever to load.

> So the question here does the browser raise any events via the accessibility API to notify assistive tech of changes to the DOM via dynamic content changes?

No. I mean, if a browser is waiting for any DOM at all then it may not present anything to a screen reader until the user decides to attempt to navigate in (or at least, this is what I've heard in both JAWS and NVDA while testing some single page apps). Sometimes you get an HTML skeleton with a <div id="app"></div> inside. That has the <title> and metadata which might be announced before the JavaScript framework in question finally gets around to filling that "app" div, but otherwise it's silent. On a "normal" page you'd get numbers of headings, links, etc on the page, but I don't always hear these on Single Page Apps.

Developers wanting to have sections that load would manually use aria-busy on the container of the loading content, but support seems thin.

> - Developers inserting the content after an action in the correct position of the DOM which we both touched upon.

Not announced by default. Browsers don't offer anything on their own. Developers would need to hook into an event if you need something after the DOMContentLoaded event (and this event itself doesn't say anything that I'm aware of, although perhaps browsers wait for this before building the a11y tree?).

cheers,
_mallory

On Mon, Jan 6, 2020, at 11:05 PM, Murphy, Sean wrote:
> Mallory
>
> I see the problem in three or four areas at this stage.
> - User interaction which you touched upon. This covers notification of
> new information being made available via ARIA or Focus change.
> - Assistive Technology being aware of the DOM being updated. This event
> change would need to be sent from the browser. Not sure if this occurs.
> My understanding is Jaws waits for the JavaScript to load or just
> before it loads. Cannot recall which order it is. So the question here
> does the browser raise any events via the accessibility API to notify
> assistive tech of changes to the DOM via dynamic content changes?
> - Developers inserting the content after an action in the correct
> position of the DOM which we both touched upon.
>
> The above are very high overview and more than likely very simplified.
> Is there anything missing?
>
> Sean
>
>
>