Re: [cssom-view][css-writing-modes] Behavior of scrollLeft in RTL or vertical-rl mode

On Wed, 30 Sep 2015 08:55:09 +0200, Xidorn Quan <quanxunzhen@gmail.com>  
wrote:

> Hi,
>
> I'm going to fix a scrolling issue for RTL mode in Gecko, whose
> solution may depend on the behavior of scrollLeft. Thus I hope to
> confirm with the working group about the behavior first.
>
> It seems that, for scrolling within RTL or vertical-rl
> element/document, the behavior significantly varies across impls. I
> made a page to test the behavior, and also listed the result I saw
> there. [1]
>
> As shown in the table in that page, in all cases with RTL or
> vertical-rl, Gecko returns 0 for scrollLeft when the scrollbar stops
> at the rightmost, and returns negative values otherwise. It seems to
> me that this behavior matches what the CSSOM View spec says [2], but
> doesn't currently match any other impl.
>
> However, since I'm not quite familiar with that spec, and the wording
> looks obscure to me, if anyone can confirm that behavior, that would
> really help.
>
> [1] https://people.mozilla.org/~xquan/scrollleft.html
> [2] https://drafts.csswg.org/cssom-view/#dom-element-scrollleft
>
> Thanks.
>
> - Xidorn
>

Hi Xidorn, sorry for the delay in replying.

Yes, the spec is intended to match Gecko. It is consistent with how  
position:absolute works, so in my opinion Gecko is most useful for authors.

I had some trouble specifying this; see  
https://lists.w3.org/Archives/Public/www-style/2014Sep/0258.html for some  
previous discussion.

-- 
Simon Pieters
Opera Software

Received on Wednesday, 21 October 2015 07:26:34 UTC