Develop Reference

How to find out what JavaScript function triggered HTML change?

I am having a problem on a WordPress site. I have a function which slides down a certain <div>. It is:
jQuery(function($){
$(document).on('click','.tb_usertask_title',function(){
var title = $(this);
var key = title.data('key');
var msg = $('#tb_msg_'+key);
msg.slideDown('fast');
}
});
After executing this function, the <div> slides up again immediately. I think this might be due another script, but I have absolutely no idea how to find which function does this. Is there any way of finding this out? Things I have tried:
Adding breakpoints in my function. This showed me that the folding up happened outside my function.
Using Firebug to break on HTML change. This however redirected to jquery.js, but I did not know how to find out which function triggered the jQuery.
Using Firebug to list the events of my onclick event, but this only showed my function.
These didn't work for me. I also searched for a way to do a function backtrace in Firebug, but without any success.

Use unminified version of jQuery (just for the test and because its more easy to debug).
Look for the dispatch function.
Put a breakpoint in the function where there is an apply usage.
After the code breaks use the F11 to navigate to the binding function.

Function not being bind at page load

I am trying to avoid my page being refreshed after submitting my form. In order to do this I've added into my javascript section
$("body").on('click',"#register",new_user_pop);
$("body").on('click',"#screen",pop_out);
$("body").on('click',"#new-user",pop_registration);
$('form[name=new-user-form]').on('submit',function(event) {
event.preventDefault();
alert("Not refreshing");
The function works properly as in order to debug it I pasted it on the Terminal from the Chrome's developer tools and it started working.
But for some reason I do not know it does not work it does not get loads at the beginning.
The previous function $("body").on('click')... work all fine.

Make sure your code runs after you've defined the HTML elements you want to attach your events to.
You can either do this by placing your script below the HTML bit you need.
Or you can wrap your code in an onready/load callback:
$(document).ready(function () {
/* code goes here */
});

Could someone point out the error in my jQuery?

I'm making a script to open all links on a page when I click a button in my toolbar. What exactly is wrong with the following code?
function performCommand(event) {
if (event.command == "open-tests") {
$('a').each(function(index, elem) {
window.open($(elem).attr('href'));
});
}
}
As far as getting to the function, it does this fine, as if I comment out the if statement and put in a simple alert, it will work as expected. However the above code does not work.

There is no standard command property of the event object provided by jQuery.
Why do you think there is one?

Did you disable your PopUp Manager or are you using any other kind of adblocker / secure plugin?
Despite that Safari refuses to window.open when called in a callback
more to read:
http://jensarps.de/2009/08/21/safari-and-window-open/

replacing content on pages that use ajax

I'm working on a extension for a fb game that adds some extra info to popup boxes, hides some useless information and run some timers so you can see how long till you have to do something even if you are not on the game page.
My problem is that a while back they went over to using ajax to change between pages and I am wondering if I am using the right approach to handle this.
I run a setInterval that checks if I am on a page where i want to add/remove soemting and i havent done it yet, if this is true I do my stuff, the code looks something like this:
function myFunction() {
if($(selector for some element I am looking for).length > 0 && $(selector for some item I add).length == 0) {
//do some stuff
}
}
setInterval("myFunction()",1000);
Is this the right way of handling ajax page change from an content script in an extension?
If so is there a better way to see if I am on the right page or if i have added to this page already other than doing a selection?

You can use livequery jquery plugin to catch when new element is created on a page:
$("#ajax-element").livequery(function({
//ajax-element is created
});
You can also listen to DOMSubtreeModified event which fires when DOM changes:
document.addEventListener("DOMSubtreeModified", function(event){
//something has changed, possibly ajax-element was added
});
There are also more specific DOMNodeInsertedIntoDocument and DOMNodeRemovedFromDocument events.

Prevent an exception with jQuery UI Tabs

I am adding some custom tabs to a jquery ui tab control.
$("#tabs").tabs("add","#tabContent0","CLICK ME TO CHANGE PAGE",0);
$('a[href="#tabContent0"]').attr("href","javascript:window.location='http://www.google.co.uk';");
Yes this is a bit of a hack, but it is exactly what i need and provide a nice way to give links back to previous parent pages.
jquery throws the following exception: "jQuery UI Tabs: Mismatching fragment identifier."
This is thrown on the line which appears to attempt to make the tab container visible in jquery ui (exact line wont help as is minified and custom build from official site).
Obviously im just redirecting but jquery has additional code to select the tab (which doesnt exist). In internet explorer, if the user has script errors enabled they will see the exception be thrown just before the window location changes, which I just cant have happen.
I cant put try catch around this code because it is the code inside jquery ui that throws the exception.
Is there anyway I can prevent this exception being thrown or achive the same thing but a different way without having to modified jquery ui ?
Edit: I am now wondering if there is a way to override the on click event hook placed on the element by jquery .. its definitely doing something there i cant see.
Edit: I have to log off now but I have made some progress, if someone can just help me get the right URL, using this code it prevents the exception, but redirects me to "http://myurl/undefined"
$('#tabs').bind('tabsselect', function(event, ui) {
if(ui.index<2) //ignore this will change to get current tab count -1 (so the end tab is left as it is
{
window.location=$('#'+ui.tab).attr("href"); //attr href is undefined, how do i use ui.tab properly to get the right url
return false;
}
});

It works OK for me in Chrome and IE8.
I also tried this code and it worked:
$("#tabs").tabs("add","#tabContent0","CLICK ME TO CHANGE PAGE",0);
$('a[href="#tabContent0"]').click(function() {
document.location='http://www.google.co.uk/';
});
Instead of changing href attribute, I add a handler on the click event of the new tab. This will make the tab to be switched and then the location changed.

From the jQuery UI docs:
$('#example').tabs({
select: function(event, ui) {
var url = $.data(ui.tab, 'load.tabs');
if( url ) {
location.href = url;
return false;
}
return true;
}
});
Though, jQuery's tabs, uh, method, ought to support passing in a selector for the tabs and panels so you could just make things links, instead of having to kick against the pricks.