Proposal to add dynamic values for aria-level (headings)

[romaingervois]

Hello,

It would be cool to be able to dynamically manage section headings via aria-level.
Three values could be used to manage a large number of cases.

• n-1 : the level is the level of the previous heading minus 1.
• n : the level is the same as the level of the previous heading.
• n+1 : the level is the level of the previous heading plus 1.

Note:

• if there's no previous heading, the default value of aria-level (level 2 as per the current specs) is applied.
• if the value is n-1 and the previous heading has a level 1, the default value of aria-level is applied.

Example with an unique code :

<p role="heading" aria-level="n+1">Article 1</p>
<p role="heading" aria-level="n">Article 2</p>
<p role="heading" aria-level="n">Article 3</p>

Context 1:

Code:

<h1>Category of articles</h1>
<p role="heading" aria-level="n+1">Article 1</p>
<p role="heading" aria-level="n">Article 2</p>
<p role="heading" aria-level="n">Article 3</p>

Result (headings):

h1) Category of articles
h2) Article 1
h2) Article 2
h2) Article 3

Context 2:

Code:

<h2>Related articles</h2>
<p role="heading" aria-level="n+1">Article 1</p>
<p role="heading" aria-level="n">Article 2</p>
<p role="heading" aria-level="n">Article 3</p>

Result (headings):

h2) Related articles
h3) Article 1
h3) Article 2
h3) Article 3

What do you think of this proposal?

Have a nice day.
Romain

[JAWS-test]

This is a very good suggestion. Above all, it would solve the problem that always occurs when external content is embedded in a page.

Example: The video player of YouTube contains a <h2> heading (= video title). This usually contradicts the rest of the page structure (e.g. if the player is located in an area with a <h3> heading and therefore the YouTube heading should be a <h4>).
But since YouTube does not know the page structure, this would be the perfect solution!

[jnurthen]

(not a comment on the proposal itself) Please note - there is no longer a default aria-level of 2 for headings. This is now defined only in the error correction section.

[pkra]

This proposal feels a lot like headinglevelstart proposed at whatwg/html#5033 (or any other discussion about the outline algorithm and/or level-agnostic heading elements).

[jnurthen]

Removing 1.4 milestone as I don't think we can look at this until the associated html issue gets consensus.

[pkra]

@jnurthen I'd suggest to just close this. The HTML side just doesn't seem likely after removing the document outline -- but if it does against all odds it'll be easy to pick up again on the ARIA end.