- From: Arthur Barstow <art.barstow@nokia.com>
- Date: Mon, 11 Mar 2013 13:39:07 -0400
- To: ext Rick Byers <rbyers@google.com>, Sangwhan Moon <smoon@opera.com>, Olli Pettay <olli@pettay.fi>
- CC: "public-webevents@w3.org WG" <public-webevents@w3.org>
Hi All, Starting with Rick's original text, applying Sangwhan's suggested changes, softening the one must to should and adding some format tags, I get: [[ <div class="note"><div class="note-title"><span>Note</span></div><p class=""> User agents should ensure that all Touch objects available from a given TouchEvent are all associated to the same document that the TouchEvent was dispatched to. To implement this, user agents should maintain a notion of the current <em>touch-active</em> document. On first touch, this is set to the target document where the touch was created. When all active touch points are released, the <em>touch-active</em> document is cleared. All TouchEvents are dispatched to the current <em>touch-active</em> document, and each Touch object it contains refers only to DOM elements (and co-ordinates) in that document. If a touch starts entirely outside the currently <em>touch-active</em> document, then it is ignored entirely. </p></div> ]] (The format of the this new Note (which is non-normative by definition) would be identical to the Note in Section 7 <http://www.w3.org/TR/2013/WD-touch-events-20130124/#mouse-events>.) Is the above text OK? Re where to put this Note in the spec, I don't have a strong preference so feedback is welcome. One possibility is to put it after Section 5.1 in a new Section titled something like "Notes for User Agents". Another option is put it in a new section after Section 5.7. WDYPropose? Re testing this behavior, given this is non-normative text, I don't think a test case is mandatory (although if someone wanted to create a test, that would be fine). -Thanks, Art On 3/6/13 12:03 PM, ext Rick Byers wrote: > On Tue, Mar 5, 2013 at 9:43 PM, Sangwhan Moon <smoon@opera.com > <mailto:smoon@opera.com>> wrote: > > Rick and Art, > > Thanks for the feedback. > > On Mar 6, 2013, at 3:12 AM, Arthur Barstow wrote: > > > On 3/1/13 9:45 AM, ext Rick Byers wrote: > >> Thanks for pushing on this Sangwhan, I agree having some wording is > >> valuable given the issues we've had. > >> > >> I want to make sure I understand what the wording means (and > ideally > >> matches our implementation). When you say 'touch sequence' you > mean > >> the sequence of events for a given touchID, right? Don't we > want to > >> be stronger than that - making restrictions across multiple > touches? > >> Perhaps something along the lines of the following (with improved > >> wording - this is rough): > >> > >> User agents must ensure that all Touch objects available from a > given > >> TouchEvent are all relative to the same document that the > TouchEvent > >> was dispatched too. To implement this, user agents should > maintain a > >> notion of the current touch-active document. On first touch, > this is > >> set to the target of the touch. When all active touch points are > >> released, the touch-active document is cleared. All > TouchEvents are > >> dispatched to the current touch-active document, and each Touch > object > >> it contains refers only to DOM elements (and co-ordinates) in that > >> document. If a touch starts entirely outside the currently > >> touch-active document, then it is ignored entirely. > >> > >> Does this match all the implementations? I'm pretty sure this > is what > >> Chrome does. Olli? > > Looks good to me. Possible adjustments, to make it a bit clear for > readers > with less background knowledge on the context: > > - TouchEvent are all relative to the same document that the TouchEvent > + TouchEvent are all associated to the same document that the > TouchEvent > > - was dispatched too. To implement this, user agents should > maintain a > + was dispatched to. To implement this, user agents should maintain a > > - set to the target of the touch. When all active touch points are > + set to the target document where the touch was created. When > all active touch points are > > This matches Chrome (and the new Opera Mobile beta) and I think Safari > as well. Firefox I'm not sure - Presto doesn't match this behavior > though. > > >> I'm ok with the wording being less prescriptive, but it should have > >> something like the first sentence above at least (this is the key > >> restriction). > > > > From the process perspective, if any new normative UA > requirement is added, the spec will need to return to Last Call > Working Draft. However, if this is more about clarifying behavior > that is already widely implemented, then this could be viewed as a > bug that requires some new text to clarify. > > > > So, which is it (new requirement or clarification needed)? > > It's closer to clarifying behavior that is already widely > implemented. Presto > doesn't do it exactly as described, but that's probably not that > big of a issue. > > > Agreed this is really just clarification of an omission. The fact > that multiple documents can't be referenced from one event follows > from the HTML5 security model (not sure which spec best covers this, > but presumably it's in HTML5 and/or others). I don't think we need to > be prescriptive on exactly how this is enforced, perhaps most of the > text should be in a non-normative note? Eg. I don't see any reason > why Presto's behavior should be considered invalid. > > Presto allows multiple "touch-active documents", which is > different from what > others are doing, but hopefully nobody will rely on that behavior. > > > Do we have a test for this? If not, who is willing to write a test? > > No, we do not have a test for this. Depending on the timeframe > that we need it > I can commit to writing one. (I'm fully booked until the end of > next week, so after that) > > > Thanks Sangwhan! Assuming we go with most of the description in a > non-normative note, then the test should be pretty limited - I guess > just make sure that the TouchEvent object only has > touches/changedTouches entries for the touch in the same document. > I'm not sure of the exact right balance here in getting good test > coverage but avoiding taking a dependency on an implementation detail > (eg. should we make sure Presto passes the test too?). > > > And yes, it would be good to get feedback from all of the > implementations including all libraries we know about. Scott, > what's the jQuery perspective here? > > Hopefully the libraries shouldn't have to care about this, but > probably better to > get a comment from Scott. > > -- > Sangwhan Moon, Opera Software ASA > >
Received on Monday, 11 March 2013 17:40:01 UTC