- From: Leif Halvard Silli <xn--mlform-iua@xn--mlform-iua.no>
- Date: Wed, 3 Mar 2010 05:41:14 +0100
- To: "public-html-a11y@w3.org" <public-html-a11y@w3.org>
Instead of an element solution to @summary, one could have an element solution to a broader concept: info notes inside the <caption>. For lack of better word: <infonote>. <infonote> could also potentially be useful inside <figcaption>. (I considered <aside>, but ruled it out.) <infonote> would not be a solution to @summary per se. Instead it is more of a solution to the incompatibility with WCAG H39[1] that HTML5 has introduced: H39 says that <caption> has a identification purpose, and thus regular block level elements (which HTML5 permits inside <caption>) should not have any place there. <infonote> would keep non-identifying content separate from the "real" identifying caption content, and thus be more H39 compatible. As to WCAG H73, then <infonote> would not eat into the @summary concept - @summary would remain as it is. However, if a 'table summary' was deemed useful to the wider audience as well, then the author could move the 'table summary' from the @summary and into an <infonote>. (WCAG H73 forbids that the content of <caption> is repeated in @summary, so one would have to choose between @summary or <infonote>, I gather.) The positive thing about <infonote> w.r.t. H73, is that it lets you move the table summary to the <caption> without breaking WCAG H39. Thus, if we adapted this proposal, then I imagine we could keep Laura's @summary proposal in full - but for a note that one could also use <infonote>. <infonote> vs <details>: Like the 1st example below demonstrates, there can be legitimate reasons to place an a note which is neither a 'table summary' nor a long table description - nor a identifying caption, inside the <caption> - <details> is not suitable for this. <infonote> is also meant as the only legal block element directly inside <caption> - I did not see that <details> was suggested as the single block element permitted inside <caption>. PS: Adding a 'table summary' inside <caption> is possible as HTML5 stands! You *can* add a table summary inside the <caption>, if you accept to break WCAG H39. The only way to (mildly) "trigger" people to place 'table summaries' inside a @summary instead of inside <caption>, is to maintain some restrictions of what <caption> can contain = no block elements. And this is of course also the only way to maintain <caption>'s identification purpose as well - hence <infonote>. <infonote> has the advantage over e.g. reusing <p> or <div> that <infonote> is "more semantic". E.g. if you use a <p>, then there is nothing that hinders that the info you started on in the first <p>, wouldn't continue in the next <p>. Whereas <infonote> is a more natural container for one specific issue related to the table. PPS: Instead of this proposal, I considered proposing a <summary> element as direct child of <caption> - it would be much simpler to define a cross-browser compatible solution, if the table summary element was allowed to be the child of <caption> rather than a child of <table>. (Shelley pointed to some problems even when we use a second <caption>.) As long as the content of such a <summary> was limited to be inline elements, then it would even work in Firefox 2. However, I figured that a) this would not solve the (unraised) issue of WCAG H39 compatibility and b) the opposition against a pure summary element from many @summary supporters isn't an inspiration either. Instead Laura's words about not distorting the purpose of @summary made me think about a "third" solution. As did John's "ghetto" comment. Of course, if a 'table summary' is placed inside a <infonote>, then there is no limit to how authors could style it - I am not sure if I understood Gez correctly in that styling would be a problem. Because if styling could be a problem, then a <summary> element would still solve *that* problem better than block elements (HTML5 as it stands) and <infonote>s. For example, AT could simply be designed to ignore any styling, emphasis etc inside a <summary> element. EXAMPLES: WCAG2 H73 example [2], with a <infonote> added: <table summary="Intersections are listed in row 1. Find the intersection closest to your starting point or destination, then read down that column to find out what time the bus leaves that intersection. Service begins at 4:00 AM and ends at midnight."> <caption>Route 7 Downtown (Weekdays) <INFONOTE>Only valid from Week 47.</INFONOTE> </caption> To give all readers access to the user guide inside @summary, one could use <INFONOTE> for that as well: <table><caption>Route 7 Downtown (Weekdays) <INFONOTE> Only valid from Week 47.</INFONOTE> <INFONOTE>Intersections are listed in row 1. Find the intersection closest to your starting point or destination, then read down that column to find out what time the bus leaves that intersection. Service begins at 4:00 AM and ends at midnight.</INFONOTE> </caption> HTML5’s <caption> example: [3] <caption>Table 1. <INFONOTE>This table shows the total score obtained from rolling two six-sided dice. The first row represents the value of the first die, the first column the value of the second die. The total is given in the cell that corresponds to the values of the two dice.</INFONOTE> </caption> [1] http://www.w3.org/TR/WCAG20-TECHS/H39 [2] http://www.w3.org/TR/WCAG20-TECHS/H73#H73-tests [3] http://dev.w3.org/html5/spec/tabular-data#the-caption-element -- leif halvard silli
Received on Wednesday, 3 March 2010 04:41:50 UTC