- From: Daniel Holbert <dholbert@mozilla.com>
- Date: Tue, 18 Nov 2014 13:12:28 -0800
- To: Bo J Campbell <bcampbell@us.ibm.com>, www-style@w3.org
On 11/18/2014 12:27 PM, Bo J Campbell wrote: > are you saying that the Flexbox is > read into the DOM in the order that it is being visually laid out? No -- DOM order is unchanged when the "order" property is modified. Under the hood, separate from the DOM tree, most browser engines have a "box tree" which represents the page layout (and which is topologically similar to the DOM tree). Gecko reorders this box tree to respond to changes in "order". As a side effect, this influences tab-index handling, because we also use that box tree for determining tab ordering. > Is there an argument that the tab index should not follow > this visual order? There was a thread about it on this list in 2012, starting with http://lists.w3.org/Archives/Public/www-style/2012Jun/0478.html fantasai posted this proposal: http://lists.w3.org/Archives/Public/www-style/2012Jul/0046.html ...and it was discussed in the subsequent CSSWG meeting: http://lists.w3.org/Archives/Public/www-style/2012Jul/0109.html (There was also a suggestion in that meeting that the property be renamed; I didn't continue digging to see if/where that was followed up on, but that's getting somewhat off-topic.) (If you haven't read those threads yet, it's probably a good idea to go through them when presenting your proposal.) I think the argument was essentially: (1) Ideally, the source (& the DOM) should represent the page's logical order, while the "order" property (and other flex properties) should be used for purely visual reordering/reversing. (2) Non-visual navigation (like speech / screen-readers, and to a lesser extent tab-index) should use the page's logical order. Hence, they shouldn't be influenced by CSS-only "order" reordering. There's also a chunk of the spec devoted to this: http://dev.w3.org/csswg/css-flexbox/#order-accessibility with some explanation & an example of an article with a later-in-the-DOM nav-bar, which is reordered to the article's left on a wide-enough screen. ~Daniel
Received on Tuesday, 18 November 2014 21:12:56 UTC