Rails spinoffs - Aug 2006 - Problem with prototype Event class and IE

Hi *,

I have a problem with the prototype Event class and the Internet
Explorer. The page is just some positioned divs and a p for debugging
output. (It is used just for understanding some other IE difficulties)
The javascript code used is the following:

   function show_clicked(event) {
      $(''DEBUG'').innerHTML += Event.element(event).id+"
clicked<br />";
   }

   Behaviour.register({
      ''div'': function(element) { element.onclick =
show_clicked }
   });

Everything is fine in Firefox, but if I try this in IE it gives an
error, when clicking on any div. The error message is
"''target'' is null
or not an object" and refers to the following line in  prototype.js;

  element: function(event) {
    return event.target || event.srcElement;
  },

Inside the Event class. Has anybody a solution to this problem or at
least an explanation, why this happens.

Greets, Tim

It''s not Prototype''s problem. IE doesn''t pass the
event object to the
handler function like Firefox (or pretty much any other browser).

You can get around it in a couple of ways:
1. Check for the event object at the top of your function, if it''s  
not there, grab window.event.
function (evt) {
     if (!evt) {evt = window.event;}
     // Do stuff
}

2. Use Prototype''s bindAsEventListener function, which ensures the  
event object is always passed to the handler.
Behaviour.register({
       ''div'': function(element) { element.onclick =  
show_clicked.bindAsEventListener(element); }
    });

On Aug 9, 2006, at 6:38 AM, Tim Bellinghausen wrote:
> Hi *,
>
> I have a problem with the prototype Event class and the Internet
> Explorer. The page is just some positioned divs and a p for debugging
> output. (It is used just for understanding some other IE difficulties)
> The javascript code used is the following:
>
>    function show_clicked(event) {
>       $(''DEBUG'').innerHTML +=
Event.element(event).id+" clicked<br /
> >";
>    }
>
>    Behaviour.register({
>       ''div'': function(element) { element.onclick =
show_clicked }
>    });
>
> Everything is fine in Firefox, but if I try this in IE it gives an
> error, when clicking on any div. The error message is
"''target'' is
> null
> or not an object" and refers to the following line in  prototype.js;
>
>   element: function(event) {
>     return event.target || event.srcElement;
>   },
>
> Inside the Event class. Has anybody a solution to this problem or at
> least an explanation, why this happens.
>
> Greets, Tim
>
> _______________________________________________
> Rails-spinoffs mailing list
> Rails-spinoffs-1W37MKcQCpIf0INCOvqR/iCwEArCW2h5@public.gmane.org
> http://lists.rubyonrails.org/mailman/listinfo/rails-spinoffs

Hi,

Am Mittwoch, den 09.08.2006, 09:09 -0600 schrieb Tom
Gregory:
> 2. Use Prototype''s bindAsEventListener function, which ensures the
> event object is always passed to the handler.
that''s it. Thanks, now everything works fine. I found a workaround
myself, but it requires patching prototype, so not really the way to
go :-)

Greets, Tim

P.S.: Does anybody know, why I never received my initial post?