497493 - Don't set mDragSession.canDrop during nsDragAndDrop.dragExit()

Status: RESOLVED WORKSFORME

(Core :: DOM: Copy & Paste and Drag & Drop, defect)

Description

[Karl Tomlinson (:karlt)]

There is no need to set mDragSession.canDrop during nsDragAndDrop.dragExit(),
as the dragleave signal indicates that the drop will not occur on this
(temporary) destination.  Calling aDragDropObserver.canDrop() can take
significant time to wait for data from another application.

Similarly, there is no need to set mDragSession.canDrop during
nsDragAndDrop.dragEnter() as a dropover event will follow the dragenter event.

Comment 1

[Karl Tomlinson (:karlt)]

(In reply to comment #0)
> Similarly, there is no need to set mDragSession.canDrop during
> nsDragAndDrop.dragEnter() as a dropover event will follow the dragenter event.

Maybe that part is necessary as the element for the dropover event (current target element) is not necessarily the same element as the dragenter event (immediate user selection) if the dragenter event is not canceled.

http://www.whatwg.org/specs/web-apps/current-work/multipage/dnd.html#drag-and-drop-processing-model

Comment 2

[Neil Deakin]

Is this still an issue? The nsDragAndDrop.js script is obsolete, not used in Firefox, and is only provided for compatibility with old code.

Comment 3

[Karl Tomlinson (:karlt)]

I haven't looked at this for a while, so haven't checked how the replacement behaves, but if nsDragAndDrop.js is not intended to be used then there's not much point keeping this bug around.

Guessing bug 545714 might be the relevant bug.