How to use jQuery's .on with Rails ajax link? - ruby-on-rails-3

Question

I'm having a bunch of problems getting jQuery's .on to work with my Rails ajax link.
Specifically, I've got this link:
<div id="item_7_tools" class="item_tools">
<a rel="nofollow" id="book_item_7" data-remote="true" data-method="post" class="book_link" href="bookings">Book this item</a>
</div>
I've trimmed some of the text in the HTML, but suffice to say that that, and my controller response work.
I click "Book this item", it goes off to the controller, the controller does its magic, and sends back my partial that replaces the contents of that div.
So I'm now trying to replace the contents with an ajax spinner while the loading is working, and that's where its going pear-shape.
I'm trying this initial bunch of jQuery code just to make sure I've got my javascript working:
$('div.item_tools')
.on('click', 'a', function() {
console.log("clicky click")
})
.on('ajax:beforeSend', "a", function() {
console.log('the a in div.item_tools is sending its ajax command');
})
.on('ajax:complete', "a", function() {
console.log('ajax request completed');
})
My understanding of that, is that when I then click any link (a) that lives within an element with the item_tools class, it will bubble up to this function, and then log the message into the console. Similarly, a link that has triggered an ajax request will get the same treatment...
(And assuming I can get that to work, then I'll go to work doing the ajax loader spinner).
The behaviour I'm seeing instead, is that when I click the link, there are no messages appearing in my console (trying this on both firefox and chrome), and my ajax link goes off and does its stuff correctly. Just completely ignoring the javascript...
Is this because my clicking the ajax link somehow has blocked the click event from bubbling up? I know that there's a way to do that, but I don't think I've done it anywhere knowingly. Unless OOTB rails/ujs does that?
So my questions:
Is there a way to tell what has had a binding attached to it?
What am I doing wrong with my javascript?
Thanks!

Answer 1

I use this all the time... and it seems to work fine.
Have you tried adding one that's .on('ajax:success')?
Besides that try putting the . for each line on the previous line...? It's possible that it gets to $('div.item_tools') and then auto-inserts a semi-colon as per javascript's standard... Although if that were the case I'd expect it to give you a JS error about the . on the next line. In any case try changing it to:
$('div.item_tools').
on('click', 'a', function() {
console.log("clicky click")
}).
on('ajax:beforeSend', "a", function() {
console.log('the a in div.item_tools is sending its ajax command');
}).
on('ajax:complete', "a", function() {
console.log('ajax request completed');
})
If worse comes to worse try just doing:
$("a").on("ajax:success", function(){
console.log('ajax:success done');
})
And see if it works without the event delegation...
Then change it to this:
$(document).on("ajax:success", "a", function(){
console.log("ajax:success with delegation to document");
})
And see if delegation works all the way up to document instead of just your item_tools
Are you sure that you've named everything right? it's div.item_tools a in your markup?

Answer 2

Turns out that the javascript was being triggered before the DOM had loaded, which meant that stuff weren't being bound...
$(function () {
$('div.item_tools')
.on('click', 'a', function itemToolsAjaxy() {
console.log("clicky click");
})
.on('ajax:beforeSend', "a", function() {
console.log('the a in div.item_tools is sending its ajax command');
$(this).closest('div').html('<img src=/assets/ajax-loader.gif>');
})
});
Added the $(function()) right at the beginning and it delayed the binding until after the DOM had loaded, and then it started working.
Figured this out by using the Chrome developer tools to stick a break on the div.item_tools selector and watched as the browser hit that even before the DOM had been loaded. /facepalm
(I removed the .on('ajax:complete') callback, because it turns out that there's a known limitation where the original trigger element no longer exists because it had been replaced, so there's nothing to perform the callback on. Not relevant to my original problem, but I thought I'd mention it.)

Answer 3

As far as i'm aware, you can either do ajax stuff 2 ways:
By using :remote => true
By using jQuery's $.ajax (or $.post).
With number 2, make sure to change your href='#'
My suggeston is to remove the :remote => true and manually make a jQuery ajax call. That way you can use beforeSend, complete, etc.
If i'm way off track here, someone please help clarify things for me as well.