Bug 111081

Summary: [Qt][WK2] Double-tap during scroll animation leaves content in suspended state
Product: WebKit Reporter: Andras Becsi <abecsi>
Component: New BugsAssignee: Andras Becsi <abecsi>
Status: RESOLVED DUPLICATE    
Severity: Normal CC: benjamin, cmarcelo, jturcotte, menard, webkit.review.bot
Priority: P2    
Version: 528+ (Nightly build)   
Hardware: Unspecified   
OS: Unspecified   
Attachments:
Description Flags
Patch none

Description Andras Becsi 2013-02-28 08:19:30 PST 
[Qt][WK2] Double-tap during scroll animation leaves content in suspended state
Comment 1 Andras Becsi 2013-02-28 08:22:15 PST 
Created attachment 190733 [details]
Patch
Comment 2 Jocelyn Turcotte 2013-03-01 03:31:21 PST 
Comment on attachment 190733 [details]
Patch

It's for those "might have been" cases that the update deferrers were good at handling.
r=me
Comment 3 Jocelyn Turcotte 2013-03-01 03:32:43 PST 
Benjamin could you sign this off?
Is this the kind of change that is considered trivial?
Comment 4 Andras Becsi 2013-03-01 04:16:21 PST 
(In reply to comment #2)
> (From update of attachment 190733 [details])
> It's for those "might have been" cases that the update deferrers were good at handling.

Yes, this bug was unfortunately present since we removed the deferrers.
Comment 5 Benjamin Poulain 2013-03-01 13:00:48 PST 
Comment on attachment 190733 [details]
Patch

Isn't panGestureCancelled() called when transitioning from a pan to another gesture?
E.g.: pan->pinch; pan->double finger scroll

If yes, this patch is wrong.
Comment 6 Benjamin Poulain 2013-03-01 13:00:49 PST 
Comment on attachment 190733 [details]
Patch

Isn't panGestureCancelled() called when transitioning from a pan to another gesture?
E.g.: pan->pinch; pan->double finger scroll

If yes, this patch is wrong.
Comment 7 Andras Becsi 2013-03-02 10:29:41 PST 
(In reply to comment #6)
> (From update of attachment 190733 [details])
> Isn't panGestureCancelled() called when transitioning from a pan to another gesture?

Yes.

> E.g.: pan->pinch; pan->double finger scroll

pan->pinch and pan->tap/double-tap, there is no double finger scroll in Qt.

> 
> If yes, this patch is wrong.

Could you elaborate?
Comment 8 Benjamin Poulain 2013-03-03 14:15:41 PST 
> > If yes, this patch is wrong.
> 
> Could you elaborate?

You would resume the content between two interactions.
Let say you do pan->pinch->pan without ever lifting the first finger. You don't expect the content to resume at any point.
Comment 9 Andras Becsi 2013-03-04 06:17:36 PST 
(In reply to comment #8)
> > > If yes, this patch is wrong.
> > 
> > Could you elaborate?
> 
> You would resume the content between two interactions.
> Let say you do pan->pinch->pan without ever lifting the first finger. You don't expect the content to resume at any point.

Currently we only explicitly prevent the content from resuming between subsequent pan gestures and do not enforce staying suspended between pan->pinch->pan.
Although it's true that the case for the pan->pinch part of the chain is currently in most cases provided as the side effect of this bug, as it was also the case when we had update deferrers.

To enforce suspended state for gesture chains when the finger is not lifted, without having corner cases where the content remains suspended, I think we need to bring back the update deferrers in some form.
Comment 10 Andras Becsi 2013-03-07 10:14:55 PST 
The issue is covered by a more comprehensive patch at https://bugs.webkit.org/show_bug.cgi?id=111751

*** This bug has been marked as a duplicate of bug 111751 ***