[whatwg] Adding mouseenter and mouseleave events

Martijn martijn.martijn at gmail.com
Thu Mar 15 12:59:32 PDT 2007


2007/3/15, Magnus Kristiansen <magnusrk+whatwg at pvv.org>:
>
> On Thu, 15 Mar 2007 20:10:33 +0100, Gareth Hay <gazhay at gmail.com> wrote:
>
> > I'm not so sure it is a workaround though.
> > If you know that the event will bubble, you can make your handler
> > prevent bubbling.
> >
> > I don't think we should be adding two new events to a spec, when the
> > existing events can work in the way you want, albeit with a line more
> > code. If we did, we'd be forever adding very specialized events.
>
> You don't seem to understand the situation. Imagine there's a parent
> element and several child elements. Every time you mouse over a child
> element, a mouseover event triggers (and mouseout on the previous
> element). This event bubbles up until it reaches the parent element. An
> event handler on the parent can only prevent the events from bubbling
> event further (which is not relevant), not from reaching itself.
>
> To prevent it using bubble cancelling you would have to attach events
> stopping bubbling to every child element of the target. Not only is this
> an unreliable way of doing it, it also interferes with potential other
> elements which actually want bubbling. The other, more practical
> workaround is to look at each incoming event and check "did this one come
> bubbling up, or does it belong here". However, workarounds do not solve
> the problem itself.
>
> With mouseenter/leave, there is no bubbling. There is no need to attach
> handlers to arbitrary elements, and no need to manually check each
> incoming event to see if it's bubbling or direct. These events are linked
> to a significant enough use case. They are no more redundant than existing
> events like click (mousedown+mouseup) and keypress (keydown+keyup).



Yeah, I sort of half remembered a situation where I really had a need for
mousenter/mouseleave.
I got in a similar situation as you describe.
I too think mouseenter/mouseleave events would be a useful addition.

Regards,
Martijn
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.whatwg.org/pipermail/whatwg-whatwg.org/attachments/20070315/f87b61c4/attachment-0001.htm>


More information about the whatwg mailing list