RE: [CSS21] bidi, text-align, and list markers

 

Hi, Aharon, all;  Aharon thanks very much for taking time to write back to me and keep me updated!


From: Aharon (Vladimir) Lanin <aharon@google.com> 
Date: Wed, 9 Jun 2010 10:24:16 -0700


> We (same group as my post yesterday morning) achieved consensus on the
> following at the "Additional Requirements for Bidi in HTML" f2f yesterday
> afternoon:

> (Section 3.10) CSS3 will include a new property, list-style-direction, with
> the values left, right, start, and match-me. [Aharon: the last is a
> placeholder name until we find something better]. The CSS initial value is
> start, which means according to the list item’s direction. 
This is a good idea.
> The match-me value is like start, but is inherited as a computed value of either left or
> right. To get markers to appear all on one side in most cases, the default
> style sheet will specify ":not(li) > ol, :not(li) > ul {
> list-style-direction:match-me;}". This will still align the list items by
> their own direction, and the user will have to explicitly use li
> {text-align:match-parent}. We can not make this the default without breaking
> the inheritance of text-align.
Yes, this is the right thing to do.
> When one actually wants the markers to appear on different sides, one needs
> to set up margins or padding appropriately.
Even then I could not quite get things to line up appropriate; see my attachment.
> [End of quote]

> The rationale here is that opposite-direction list items as they are
> currently displayed are broken. The marker gets cut off in most cases, and
> in different ways in different browsers. The reason it gets cut off is that
> it, like the same-direction marker, is supposed to show up "in the gutter",
> i.e. in the margin or padding. The list sets up the margin on the start
> side, so the same-direction list items' markers have where to show up, but
> the list does not set up a margin on the end side, and the
> opposite-direction markers get cut off. 
Opposite-direction markers get misaligned in IE 8 but not cut off apparently that I could see.
But I still feel that the developers need to fix this.
> This can not be fixed by the list
> automatically leaving a margin there because this would waste real estate in
> the 99% case where there are no opposite-direction list items.
I think the browsers could check for opposite-direction list items with opposite-direction markers; however; that's just an opinion.

> So, given that opposite-direction list items are broken, and we thus don't
> need to worry about backward compatibility, and that all markers on one side
> is what's usually wanted anyway, we allowed ourselves to try to make it the
> default.
I do not finally think there was a consensus that this should be the default -- though it does improve the list appearance for me personally to have the markers on the same side.
> Fantasai and Tab, I do not remember, why did this have to be done in the
> default style sheet? I.e., why couldn't the CSS initial value for
> list-style-direction be match-me to begin with?
I hope I can answer this for everyone -- hope my info is right; according to Fantasai there are adequate examples of documents (books) where the desired behavior is to have the bullet line up with the list item directionality:
see Fantasai's post on http://lists.w3.org/Archives/Public/public-i18n-bidi/2010AprJun/0064.html
"The CSS Working Group does not have any objections to adding controls to
this in CSS3 Lists, and in that case the HTMLWG may adopt a different set
of default styling rules for the HTML list elements. However the CSSWG is
resolved that the default behavior in CSS will not change."
For some examples of the use of lists with item's markers aligned differently, see Adil's post at:
http://lists.w3.org/Archives/Public/public-i18n-bidi/2010AprJun/att-0060/00-part
Hope my response clarifies the issue of default-alignment some.
Best,
C. E. Whitehead
cewcathar@hotmail.com
> Aharon