- From: Simon Pieters <simonp@opera.com>
- Date: Mon, 26 May 2014 12:51:35 +0200
- To: "Robert O'Callahan" <robert@ocallahan.org>
- Cc: "L. David Baron" <dbaron@dbaron.org>, www-style <www-style@w3.org>
On Mon, 26 May 2014 11:50:50 +0200, Robert O'Callahan <robert@ocallahan.org> wrote: >> It was the API's "auto" value that was under discussion. Currently the >> CSS >> property does not have an "auto" value. > > > Yes, I was referring to the CSS property. It seems to me having an 'auto' > value for that property that falls back to UA/platform defaults would be > better than making 'smooth' do that. In particular it seems that > currently > "smooth" in the JS API overrides UA defaults but CSS > scroll-behavior:smooth > does not override UA defaults. It would be better if they were > consistent. No, the API "smooth" honors user preferences just like the CSS property. In particular, the spec allows the UA to ignore the 'scroll-behavior' property, which makes both navigation scroll and API scrolls be instant. See http://dev.w3.org/csswg/cssom-view/#perform-a-scroll step 2. Technically, the spec also allows the UA to follow the "smooth scroll" steps and let that be a zero-time no-animation scroll, since it's UA-defined. >> But then I'm not sure what the use-cases are for the "initial" and >>> "smooth" >>> values of scroll-behavior. >>> >> >> "instant" is the initial value, and gives the same behavior as we have >> today. >> >> "smooth" allows the UA to do the scroll over a period of time in a >> UA-defined manner for scrolls triggered from navigation and from the >> scrolling APIs (unless the script specified "instant" or "smooth" >> explicitly). >> > >> For use cases, please see http://www.w3.org/mid/op. >> ww4mdlp2idj3kv@simons-macbook-pro.local >> > > Thanks. I guess that makes sense though it means scroll-behavior is a > very > narrowly-useful property. I'm not sure it's worth having to be honest, > assuming we add the JS API. OK. I thought the CSS property was worth having, but if implementors disagree then there's not much point having it in the spec. -- Simon Pieters Opera Software
Received on Monday, 26 May 2014 10:52:08 UTC