- From: Simon Pieters <zcorpan@hotmail.com>
- Date: Tue, 29 Nov 2005 13:46:23 +0000
- To: public-comments-wcag20@w3.org
Hi, I created a test suite[1] to test how img, iframe, embed and object works in current UAs. I've discussed correct pass conditions on the WHATWG list[2], so I now believe the test suite is correct. I've checked the results in IE6, Firefox 1.6a1 and Opera9, and compared with what is recommended in HTML Techniques for WCAG 2.0. >H46: Using null alternative text and no title attribute on img elements for >spacer or purely decorative images. This guideline seems a bit backwards. Authors should use CSS for purely decorative images. >H48: Using the body of the object element. What does "body" mean here? I suggest replacing it with "fallback content". >H50: Using longdesc. >[...] ><img src="97sales.gif" alt="Sales for 1997" longdesc="sales97.html"> "Sales for 1997" seems like appropriate title text, but inappropriate alternate text. The alternate text should probably be something like "The sales have increased by NN% for 1997.". >H63: Using alt attributes on applet elements. Why? <applet> can take fallback content as described in H62, which in itself is better than an alt attribute since attributes don't allow markup. Further more, I know of no implementation that supports the alt attribute for <applet>. I suggest dropping this guideline in favour of H62. >H64: Using noembed with embed. >H72: Providing alternative content for iframe. Contents of <iframe> and <noembed> are not fallback content for the included content, they are fallback content for the element types themselves (just like <noscript> and <noframes>). Contents of <iframe> will be rendered if and only if <iframe>s are not supported. Contents of <noembed> will be rendered if and only if plugins are disabled. Should the included format not be supported or return a 404 or 410 response, then there is no fallback content. <iframe> and <embed> do not have the sort of fallback content that <img> and <object> have. Perhaps H93 and H72 should be merged together. >Editorial Note: Is it true that noembed can go either beside or inside >embed? Is there a preference? <embed> is an EMPTY element type, just like <img>. It can't have any contents. >H65: Using alt attributes on embed elements. There is no alt attribute for <embed>. At least there are no implementations of an alt attribute for <embed> that I'm aware of. Since <embed> and <noembed> are not defined by HTML4, I suggest dropping H64 and H65. [1] http://zcorpan.1go.dk/test/html/embedded/ [2] http://listserver.dreamhost.com/pipermail/whatwg-whatwg.org/2005-November/thread.html#5133 Regards, Simon Pieters
Received on Tuesday, 29 November 2005 13:47:04 UTC