[css3-flexbox] status and issues

I see from recent communication on www-style and from F2F discussion that there is work on the way to implement the newest flexbox draft [1].

I would like to comment on status of flexbox spec and on some known issues. It should be useful to understand for new implementers or anyone interested. As a co-editor of the spec, I have it on my list, but it has not been a priority for a while as IE10 implementation (based on 2009 spec [2]) is being finalized and it is not open for experimental changes. Now it seems we need to identify and resolve spec issues soon so that there is a stable spec to converge to.

There are a few places that are set up to track the spec issues:


*         W3 official tracking system [3] (currently 8 issues, all for 2009 spec)

*         CSSWG Wiki [4] (currently has a set of use cases, no open issues)

*         "ISSUE" notes in the spec (about a dozen now)

*         www-style

Ideally there should be one place for tracking issues (probably CSSWG Wiki).

I am currently working on identifying key issues and on some solution options. At a very high level, the list should include


1)      Adding multiline flexbox to the spec. Multiline flexbox (as defined in 2009 spec) is implemented in IE10 and is found valuable [5]. It is not in the new spec (probably because there were no implementations when the new spec started), it should get back there.

2)      Direction/orientation is not easily extended to support multiline flexbox [6]

3)      There are 3 ways to set flexibility: "flex()" function, "fl" unit and "auto" (on margins). It is workable but confusing.

(Tab may have a separate todo list... If there is something in it that I have not mentioned, Tab, can you share?)

I hope this helps in understanding the spec status and what to expect. I would be reluctant to set any deadlines for spec updates (as it was not touched for some time)... Implementers can help speed up the progress by bringing up issues and commends (as they already do at this list).

Alex

[1] http://www.w3.org/TR/css3-flexbox/
[2] http://www.w3.org/TR/2009/WD-css3-flexbox-20090723/

[3] http://www.w3.org/Style/CSS/Tracker/products/28
[4] http://wiki.csswg.org/spec/css3-flexbox
[5] http://ie.microsoft.com/testdrive/HTML5/Griddle/Default.html#popular
[6] http://lists.w3.org/Archives/Public/www-style/2011Jun/thread.html#msg37