Bug 76244

Summary: REGRESSION(r100111): A 'change' event does not fire when a mouse drag occurs to switch elements in a listbox
Product: WebKit Reporter: Kent Tamura <tkent>
Component: FormsAssignee: Kent Tamura <tkent>
Status: RESOLVED FIXED    
Severity: Normal CC: ap, dglazkov, morrita, rakeshchaitan, webkit.review.bot
Priority: P1    
Version: 528+ (Nightly build)   
Hardware: All   
OS: All   
Attachments:
Description Flags
Patch
none
Patch for landing none

Description Kent Tamura 2012-01-12 21:16:15 PST 
Reported at http://code.google.com/p/chromium/issues/detail?id=110068.


<select id="sel1" size="4" onchange="alert('event fired: ' + document.getElementById('sel1').value);">
<option>RED</option>
<option>GREEN</option>
<option>BLUE</option>
<option>YELLOW</option>
</select>

If you select an option by mouse dragging (not clicking), 'change' event doesn't fire. This problem was made by r99667 or r100111.
Comment 1 Kent Tamura 2012-01-17 20:43:22 PST 
The root cause is that the mousedown handling in listBoxDefaultEventHandler() updates m_lastOnChangeSelection. If the listbox is scrollable, mousemove events are not dispatched.
Comment 2 Kent Tamura 2012-01-17 22:35:18 PST 
Created attachment 122874 [details]
Patch
Comment 3 Hajime Morrita 2012-01-17 22:51:58 PST 
Comment on attachment 122874 [details]
Patch

The test shows the evidence.
Comment 4 Kent Tamura 2012-01-17 23:09:15 PST 
(In reply to comment #1)
> The root cause is that the mousedown handling in listBoxDefaultEventHandler() updates m_lastOnChangeSelection. If the listbox is scrollable, mousemove events are not dispatched.

Correction: mousedown -> mousemove

BTW, HTMLSelectElement has multiple functions to update option selection, and they are confusing. We had better refactor/rename/document them.
Comment 5 WebKit Review Bot 2012-01-17 23:27:33 PST 
Comment on attachment 122874 [details]
Patch

Attachment 122874 [details] did not pass chromium-ews (chromium-xvfb):
Output: http://queues.webkit.org/results/11282082

New failing tests:
fast/forms/select-multiple-elements-with-mouse-drag-with-options-less-than-size.html
Comment 6 Kent Tamura 2012-01-18 02:21:28 PST 
(In reply to comment #5)
> (From update of attachment 122874 [details])
> Attachment 122874 [details] did not pass chromium-ews (chromium-xvfb):
> Output: http://queues.webkit.org/results/11282082
> 
> New failing tests:
> fast/forms/select-multiple-elements-with-mouse-drag-with-options-less-than-size.html

The test didn't fail on Apple Mac and Chromium Mac with the patch.
Comment 7 Kent Tamura 2012-01-18 18:30:52 PST 
Created attachment 123050 [details]
Patch for landing
Comment 8 WebKit Review Bot 2012-01-18 22:52:12 PST 
Comment on attachment 123050 [details]
Patch for landing

Clearing flags on attachment: 123050

Committed r105386: <http://trac.webkit.org/changeset/105386>
Comment 9 WebKit Review Bot 2012-01-18 22:52:17 PST 
All reviewed patches have been landed.  Closing bug.