Question

jQuery now allows you to use live to handle custom events, something I’ve used in my latest project and found very handy. I have come up against a limitation/bug, however, that I’m hoping someone will be able to help me with.

When you trigger an event, you can pass additional array of data too, like this:

 $(this).trigger('custom', ['foo', 'bar' ]);

If you were just using bind, you could absolutely access these variables. However, if you’re using live, it turns out that you have no access to data as far as I can tell. Am I wrong? Is there another way?

Here is some demo code to illustrate:

 $().ready(function() {

    $('button').click(function(){
        $('<li>Totally new one</li>').appendTo('ul');
    });

    $('li').bind('custom', function(e, data) {
        // this one works fine for old elements, but not for new ones
        $('#output1').text('Bind custom from #' + e.target.id + '; ' + data);
    }).live('custom', function(e, data) {
        // this one triggers for old and new elements, but data is useless
        $('#output2').text('Live custom from #' + e.target.id + '; ' + data);
    }).live('click', function(){
        $('div').text('');
        // just using click count to illustrate passing data in the trigger
        var clicks = $(this).data('clicks');
        if(typeof clicks == 'undefined') clicks = 1;
        $(this).trigger('custom', ['Times clicked: ' + clicks ]).data('clicks', clicks + 1);
    });
});

And the related HTML:

<button>Add</button>
<ul>
    <li id="one">First Item</li>
    <li id="two">Second Item</li>
    <li id="three">Third Item</li>
</ul>
<div id="output1">Result 1</div>
<div id="output2">Result 2</div>

Answer 1

It looks like the easiest approach may be to use the format described in the last “alternate” example at http://docs.jquery.com/Events/trigger#eventdata. The example uses an object literal to specify the event object, in which you can create custom properties. I also tried the approach you described above to no avail, but the alternate format works for me. So instead of calling

$(this).trigger('custom', ['Times clicked: ' + clicks ])

try

$(this).trigger({type:'custom', clicks: clicks});

and then reference it in the event handler of your “custom” event via:

"Times clicked: " + e.clicks;

Hope that helps!