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Re: H1 header in iframe


From: adam solomon
Date: Aug 26, 2010 12:33AM

Putting HTML5 aside for the moment, It seems that configuring the header hierarchy in a secondary document will create a double standard. Most of the time, iframe content will not be able to be controlled - it is simply imported. Therefore it would seem that one standard is more appropriate, namely always treating the secondary document as a stand-alone even when we can configure the html.

> Date: Thu, 26 Aug 2010 09:04:09 +1200
> Subject: Re: [WebAIM] H1 header in iframe
> On 26/08/10 02:32, John Foliot wrote:
> > As an additional point to Jared's, HTML5's<hgroup> element will be of
> > significant importance here (I believe) as the browser will be
> > 're-interpreting' headings based on the total document's hierarchal
> > structure (see: http://html5doctor.com/the-hgroup-element/ for a good
> > over-view)
> >
> > In effect, mark up each document as appropriate if it were a stand-alone
> > document (so yes, include at least 1<h1>) but when a 'container' document
> > imports such secondary documents (inside the<hgroup> element) the browser
> > "knows" that even though the imported document starts with an<h1>,
> > because it is inside a document that already has an<h1> that this second
> > instance, in this context, is actually a sub-heading (ergo<h2>) of the
> > parent document, and adjusts its hierarchal semantic to reflect this.
> > (Yes, it's kind of mind-bending at first, but actually quite intelligent
> > and useful. - Read the article, it does a much better job than I of
> > explaining it)
> >
> John, are you referring to HTML5's outlining algorithm and sectioning
> content? I thought that the <hgroup> element can only contain headings
> (H1-H6) and is primarily for title and subtitle or tag line groupings.
> On the other hand, your account of marking up headings in container and
> secondary documents sounds like the way that HTML5 deals with sectioning
> content and headings and implied sections and subsections when coming up
> with the document outline.
> From what I can figure out, and similar to what you describe, if the
> stand-alone secondary document begins with an H1, and is imported into a
> <section> element within the container document (and an <iframe> could
> be loaded within a <section> element, I believe), the hierarchical
> semantic of the H1 in the secondary document will be adjusted to fit in
> with the document outline and heading structure of the surrounding
> container document. In fact, no matter what level heading the secondary
> document starts with, if loaded within another HTML5 sectioning element,
> its position in the document outline will be accounted for based on the
> position and nesting of its section.
> Of course, that this works will depend on users having HTML5 supporting
> technology, so, as you indicated, Jared's suggestion to mark up the
> <iframe> document with headings that will fit in properly with the
> heading structure of the container document is still the way to go
> (though this could be probably be combined with an approach using HTML5
> sectioning elements).
> The info and examples at
> http://www.w3.org/TR/html5/sections.html#headings-and-sections are
> actually pretty helpful, I found, especially considering it's a spec.
> Jason Kiss