- From: Peter Sorotokin <psorotok@adobe.com>
- Date: Tue, 18 Jan 2005 22:43:25 -0800
- To: Boris Zbarsky <bzbarsky@MIT.EDU>
- Cc: Jon Ferraiolo <jon.ferraiolo@adobe.com>, Cameron McCormack <cam-www-svg@aka.mcc.id.au>, www-svg@w3.org
At 06:56 PM 1/18/2005 -0600, Boris Zbarsky wrote:
>Peter Sorotokin wrote:
>
>>>>>2) That the implementation is keeping the event listeners for the two
>>>>>types in
>>>>> separate lists (is this desirable? Should registering a listener
>>>>> for both
>>>>> types involved make it get the event twice?).
>>>>
>>>>You can do it per-listener rather than on per-list basis; but I'd keep
>>>>two separate lists.
>>>
>>>
>>>In other words, a listener registered for both event names would indeed
>>>get the event twice?
>>No, in this case each event listener entry in the list would have to
>>store an event type for which it was registered (also would be needed for
>>unregistering).
>
>I'm sorry, but I think you lost me. Say I have an event listener named
>"listener" and an event target named "target". We have our two event
>types "type1" and "type2". I execute the following code:
>
> target.addEventListener("type1", listener, false);
> target.addEventListener("type2", listener, false);
>
>when the event fires, how many times will my listener's handleEvent method
>be called?
Twice, IMHO. They are still different events - even if they are
"equivalent". I think we'd get in trouble with the DOM otherwise.
> Please note the provisions on addEventListener for registering
> identical listeners.
>
>Further, what is the behavior of:
>
> target.addEventListener("type1", listener, false);
> target.removeEventListener("type2", listener, false);
Again, IMHO, you still have listener for type1.
>?
>
>The answers to these questions should be clearly documented in the
>specification of what it means for the two event names to be "equivalent".
Agreed.
Peter
>-Boris
Received on Wednesday, 19 January 2005 06:43:36 UTC