- From: Ramón Corominas <listas@ramoncorominas.com>
- Date: Fri, 21 Feb 2014 00:54:30 +0100
- To: Jonathan Avila <jon.avila@ssbbartgroup.com>
- CC: w3c-wai-ig@w3.org
Hi, Jonathan and all, [Ramon] or low vision users could simply not change the designer's interface and also receive the visual info [Jonathan] This is a very sad but familiar comment that we hear. The fact is people with low vision need to change the display aspects of the interface to have equal access -- a civil right in many countries -- to information and communication technology. Ouch! Please do not interpret my words that way, I am not attacking any civil rights here <wink> [Jonathan] That may mean increasing the size of the text, or changing individual display attributes of the text. Since I *do* have low vision, I think I am quite aware of what changing the interface means, including settings for font-sizes and typography, colours, highlighting of headings and other structures, focus enhancements, form field borders and visual identification, link underlining, justification and line-spacing of text, etc. So I am not saying that users should not change the interface, what I'm saying is that certain changes can destroy visual clues that are present in the original design. "Determinability" is not equivalent to "semantics", and many design conventions or visual clues are difficult to convey to users that cannot see them. For example, design can be modern or classic, intense or quiet, funny or serious... And we don't have a simple way to convey these moods to a blind user, apart from the general tone of the text. Wayne: I think you have here a really interesting topic for your talk... Shouldn't the mood of the page be "programmatically determinable"? Isn't an essential part of the "visual information" of a page? <wink> [Jonathan] If a user with low vision decides to change the visual appearance of headings they would have access to the heading levels and thus the hierarchy structure of the document. Maybe, or maybe not. Depending on the type of "highlighting" that the user decides to apply. For example, for headings within the text of an article it can be helpful to establish certain font-sizes or left-paddings that help to identify the article's structure. However, if these same custom styles are applied to headings for other UI elements, the original visual clues can be destroyed and lead to more confusion for the low vision user. For example, a designer may use <h2> to markup "main menu", "search utils", "toolbar", "Latest posts" and so on. In my opinion, this makes sense for a blind user, but if the low vision user establishes the same font-size for those <h2> than for the text in the article, this change is probably generating a visual "importance" (= hierarchy) for those headings that they really do not have. Should we take this into account and mark them as <h3> or <h4>, thus skipping levels? Should every level-X heading have always the same size (or even visibility)? With this in mind, let me turn back to my sentence: "low vision users could simply not change the designer's interface and also receive the visual info". As a low vision user, I have many ways to style headings in a way that I can identify them. For example, I can set custom typographies or colours, add special outline effects, change them to uppercase, add margins/paddings, etc. In general, all these effects will allow me to identify the headings or even their levels without essentially changing the original design. However, if I apply fixed font-sizes for every level-X heading regardless of their context, I am eliminating the original visual hierarchy, which may be different to the "programmatically determinable" structure. This is because visual design often conveys other hierarchies that cannot be easily translated to any HTML semantics, although of course we must do our best to convey a *meaningful* structure. [Jonathan] Granted HTML5 heading methods do cause some issues in this area -- but that is an item that was overlooked and I believe can be addressed. Unfortunately, I guess this is an issue that cannot be addressed with CSS only. An <hx> != <h1> in different sections of the same depth can end up being of different level in terms of the outline, so I don't see how to address this without at least using JS. Example: <main> <h1>I am level-1</h1> <section> <h2>I am level-2</h2> </section> <section> <h1>I am also level-2</h1> <h2>So I ended up being level-3</h2> </section> </main> [Jonathan] Aria-labels are of no use for users with low vision because they are not exposed by user agents to people who aren't using screen readers. That is exactly what I am saying. If we consider that the "programmatically determinable" concept requires a strict interpretation so everyone receives the same information, then @aria-label cannot be used to meet SC 1.3.1, since the information that it conveys is lost for non-screenreader users. Many other techniques that we are accepting should also be revised (for example, @title attribute would never be a valid way to label a form field). In any case, @aria-label is probably giving more information to the blind user than the visual information given to sighted users. As a side note, there are no ARIA roles to convey the semantics of many of the text-level HTML elements... Do you consider this a bug of the ARIA spec? Should we add those equivalent roles to ARIA? In the other hand, there may be other ways to convey semantics that do not imply HTML tags or ARIA roles, such as microdata, microformats, web components... In principle they might lead to "programmatically determinable" ways of conveying the visual info, but the real issue will always be the lack of accessibility support, not the semantics. [Jonathan] Ideally, heading levels by themselves would communicate the proper information without requiring the user to see certain styles. I believe one of the main points of HTML is to provide document structure that is separate from presentation. The web is not one size fits all -- its one size fits one. Of course, but "understandable" is different from "exactly the same". My point in this thread is that a <dfn> -or similar- tag might convey *more* information to the blind user than the visual styling is doing to the sighted user. The sighted user must deduce that the italicized word ia a definition term *after* reading the text. The reality is that <dfn> and similar tags have no accessibility support (nor specific roles), so in the Real World it is irrelevant -for blind users- if we mark these contents as simple spans. In summary, although semantics can help to achieve determinability they do not guarantee it; and conversely, the lack of semantics does not necessarily prevent determinability. Regards, Ramón.
Received on Thursday, 20 February 2014 23:55:48 UTC