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Select2 dropdown menu persists after select removed from DOM

I am using select2 version 4.0.2(rc1)
What I am seeing is that when using select2 with isMultple=true, opening the dropdown and then dynamically removing the select from the DOM, the menu sticks around.
You can see it happening in the select2 examples by focusing on control so you see the time zone options, then in the console typing $('.s2-example').remove(). The list of options sticks around.
Edit: Above is an example of what I am trying to work around. What is happening in my case is the dom is being manipulated to remove the select box by a framework in such a way that I can't hook into it before it happens. What I am trying to do is find a way to respond to the element being removed in the hopes that I can manually remove the options list if it exists.
I'm trying to figure out a clean approach to handling this. I've tried hooking into destroy like so:
$("#select-2-id").on("destroy", function(){...})
but destroy doesn't appear to be fired.
I have considered using a mutation observer but that feels kind of hacky to me. Could anyone suggest a better way to handle this? Any advice would be appreciated. Thanks!

Definitely buried in the documentation (under adapters), but you should be calling the destroy method on the select by passing "destroy" to the jQuery object's .select2() method
$(".js-example-basic-multiple").select2('destroy');
This destroys the instance. You can then safely call .remove()
$(".js-example-basic-multiple").select2('destroy').remove();

Trigger TypeAhead suggestion selection

For the life of me I cannot figure out how to trigger a suggestion selection on a TypeAhead input
I've tried all kinds of things like
.trigger('suggestionClicked', $('.tt-dropdown-menu .tt-suggestion:nth-child(1)'))
I suppose there are really two parts to this problem.
1. Properly selecting the actual TypeAhead object.
I do this primarily by focusing (focus()) on the input field, and then using jQuery to find the element that is active ($(document.activeElement)). This might not be the best way. It's quite difficult to test in the browser web-inspector because every time I go to the console I lose focus and then the menu disappears (literally removing the results from the DOM)
2. Triggering the correct event.
I'm not sure exactly on which object or which event to trigger, but my best guess is either suggestionClicked on either the TypeAhead object or the TypeAhead.Dropdown object. Second best guess would be click.tt.
I might be overthinking this.
If you really care about the reason behind this, it's because I need to test the functionality via Capybara/Selenium.
I've been browsing the source code on github for some insight.
Here is a step in my Capybara attempt. I feel like I'm getting close but it's not there yet.
steps.rb
Then /^I select result number "([^\"]*)" from typeahead$/ do |num|
find('.tt-dropdown-menu')
#within('.tt-dropdown-menu') do
page.execute_script %Q{$(document.activeElement).dropdown().trigger('suggestionClicked', $('.tt-dropdown-menu .tt-suggestion:nth-child(#{num})'))}
#end
end

knockoutjs - object's changeTracker/dirtyFlag triggering immediattly

I recently found and applied the changeTracker/dirtyFlag approach successfully in my code and everything was good. Very neat and useful. Though, today, I was trying to use it again and something weird was happening: the somethingHasChanged trigger was firing as soon as I opened the page.
I looked, searched and nothing. I was not doing any change to the observables after setting the tracker.
After a couple of hours of this, I found the root of the problem:
One of the observables is binded to a <select> element thus setting the currently selected <option>.
If I remove this binding, it no long triggers.
I don't know why this happens, since the value is only read (supposedly).
Any thoughts on this?

My guess would be that you are binding against numeric values and the selected one is being written back to your view model as a string, as KO reads it out of the DOM element.

javascript function "createCallback" called >50 times when I use addClass/removeClass in Firefox

I'm working on a web app in ASP.NET 2.0 that involves several GridView elements. When users click one of the rows in a grid, that row needs to show its selection by changing color. Each row has attributes set to identify its record type and unique ID:
<tr data-elementType='myType' data-myID='12' onclick='selectionFunction();'></tr>
I accomplish the selection through a javascript onclick handler on each row that calls a function that:
Removes the selected class from the previously selected row
Adds the selected class to the new selected row
Updates the value of a hidden field with the new selected unique ID so server-side code can know which element to perform an action on when a button is clicked (view, delete, etc).
One of these grids now has just over 700 records in it. In Firefox 3.6, the selection operation on this grid is horribly slow (about two seconds); in other browsers (even IE 7 and 8) it's not a problem. I put console.log statements at the start and end of the selection function, and in Firebug they show up very fast at the end of the delay, suggesting that it's not the selection function that is slowing things down. I used the profiler in Firebug and it says that "createCallback", which is defined in one of the "ScriptResource" script files generated by ASP.NET, is taking the huge majority of the time. What is createCallback and why does it seem to be so slow in Firefox 3.6? Is it a bug in FF, or is it a problem I can solve?
UPDATE: I am, of course, using jQuery to add/remove classes from the rows. I've been working with jQuery 1.5.2 and jQueryUI 1.8.11, but I updated to the latest (1.6.2 and 1.8.14 currently) to no avail. I tried putting a breakpoint in createCallback to see where it's getting called, and when it breaks there it's several frames down in the call stack from my call to removeClass. Here is what the stack looks like in Firebug:
createCallback() - in ScriptResource.axd?......
wherever possible trim: trim ? function(text=" ") - in jQuery
removeClass(value="selectedRow") - in jQuery
removeClass(classNames="selectedRow", speed=undefined, easing=undefined, callback=undefined) - in jQueryUI
selectionFunction() - in my .aspx page
onclick
I don't understand why jQuery is triggering an ASP.NET generated function like this.
UPDATE 2: some more investigation has provided some more detail. It seems that this "createCallback" function is getting called A LOT when I use addClass/removeClass, and it's happening in both Firefox 3.6 and Firefox 5. I found the same function in Chrome and put a breakpoint on it, and it's not getting called at all, so this seems to be a Firefox thing. I put a breakpoint on the function/line in question and selected a row, and the breakpoint got it 57 times. Only the first two involved me calling removeClass and addClass; the rest had createCallback several times in the callstack, and sometimes BeginRequestEventArgs too. I've noticed it getting called also when I mouseover other jQueryUI stuff on the page (tabs), when jQuery uses addClass and removeClass. But why is it getting called so many times when I do work on tr elements?
I'm changing the title and tags to reflect the real issue.
UPDATE 3: createCallback is getting called about the same number of times whenever I select a row in any of the grids, even if it only has 6 rows in it. But in that case it's not a performance problem, and the profiler shows it only taking about 30% of the execution time, while it's at least 80% when I profile selection on the larger table. So createCallback seems to perform worse when it's used in the context of more stuff visible on the page. But it still seems like jQuery shouldn't cause a call to createCallback, especially since I couldn't fine any references at all to it in Firebug's script search. And it appears to only get called in Firefox!
Note also that all of these grids are on the same page, but only one is visible at once, because I'm using jQueryUI tabs.
UPDATE 4: I managed to get something similar up on jsFiddle as requested. See here. In Firebug, find createCallback and set a breakpoint (just below my click handler in the script, where it begins with Function.__typeName = "Function"; Function.__class = true; Function.createCallback = function (b, a) and reload the page. I get a lot of calls to it.

I have very little knowledge of ASP however it sounds like your problem is purely client side.
Declaring on "onclick" event for each row is not the most sensible way to handle the rows being clicked. Especially when you get into the quantity of rows you're talking about (~700+).
A better way would be to add a click event handler to the table and figure out what is clicked when it happens. I have written an application where a similar size table is being handled and we're not seeing anything like the lag you're experiencing upon click. there may well be other factors causing your click events to slow down however I would still suggest something along the following lines is worth implementing in any case:
$(function(){
var rowSelectedClass = 'rowSelectedClass';
$('#myTableID').click(function(e){
if(e.target.nodeName === 'TD'){
var $tr = $(e.target).parent();
$('tr.' + rowSelectedClass).removeClass(rowSelectedClass);
$tr.addClass(rowSelectedClass);
// ....
// Do whatever else you want to do when the row is clicked
// ....
}
});
}
A good article to take a look at which advocates this method (and a few other handy jQuery tips) can be found here: http://www.artzstudio.com/2009/04/jquery-performance-rules/#leverage-event-delegation
Also worth noting that if your table has rows added dynamically after the page is loaded then consider using .live() instead of .click().
UPDATE # July 28th 2011 9AM
Having taken a look at the source more closely, I think the supposed calls to "createCallback" are a red herring. The line within your original jsFiddle source which contains the "createCallback" function is actually a really long string (~90,000 characters) of javascript. I think the fact that "createCallback" is the first function within that string is misleading Firebug's profiler. When you profile your original page's load, there are 2261 calls and as you said, there appear to be lots to "createCallback"
I've "beautified" (hate that phrase) this long JS string via http://jsbeautifier.org/ to make it readable and re-added it to a jsFiddle page. You can see it here: http://fiddle.jshell.net/KvpmE/1/show/. Now when you profile this page's load you'll see a similar number of calls (2267 - not sure what happened to the other 6!) but importantly not a single one to "createCallback".
I still can't offer any solution though because essentially I've been unable to re-create your original issue which was that there was a 2 second lag in Firefox 3.6 when clicking a row.
Is this still the problem you're having?
Could you try and see whether you can re-create the problem within the updated jsFiddle page?
Also try and add the de-minified JS to your page to see if it helps you track down the actual functions being called when the row is clicked and therefore where the lag is taking place.

Mr. Jefferson,
It really sounds to me like you're actually performing a postback without knowing it. Have you set a breakpoint on the server side yet to see if something is inadvertently firing your update panel? It really sounds like some kind of postback is happening that is requiring a reload of dependant scripts.
I say this because 1) the problem you're having makes absolutely no sense - you're 100% on the money with JQuery and the ASP.NET Client Framework not even knowing they're neighbors in this case, and 2) the BeginRequestEventArgs instantiation sounds like the PageRequestManager thinks it should be doing something in response to your triggers... You could also try breaking out Fiddler and just doing a quick sanity check to make sure some update panel of yours isn't firing. There should be no HTTP traffic during the ops you're describing.
Sorry if this is an absolutely useless post for you, but with all of the work you've gone through to troubleshoot the client side it can't hurt to set a server side breakpoint just to do a quick sanity check / occam's razor...
Good luck - happy coding.
B

Function.createCallback is used a lot internally by Ajax Toolkit and maybe its being called within your code unintentionally too http://msdn.microsoft.com/en-us/library/dd409287.aspx.
Since this is browser dependent, I would check code paths that are executed based on a specific browser.
Another clue to look for is if you're having any Ajaxtoolkit components for the grid or its individual rows as that would explain the increase in number of calls with the increase in rows.
There is also Type.createCallback function (http://msdn.microsoft.com/en-us/library/bb397568.aspx) so if you have any Type related code or methods, I would check those.

Testing jQuery change event using Watij

I have a select list where a change event has been bound to the element using jQuery. Something like this:
$("#someId").change(function() {..});
When someone chooses a new option in the select list, another part of the UI will change accordingly. Now this works fine when I use the mouse and click things, however, when using Watij to write my tests I need the jQuery change event to fire which it isn't doing.
The Watij test will correctly choose the select option required but the actual event does not get triggered. I have tried calling fireevent("change"); and fireevent("onchange"); to no avail. I have also tried ie.sendKeys("{ENTER}"); and ie.sendKeys("{TAB}"); which also does not seem to do the trick.
Any ideas?

The only solution I've found so far is to roll back the version of jQuery in use. I'm currently using version 1.4.1 (the offending version in regards to the testability of the change event on select boxes) and after going back to version 1.2.6 the problem goes away.

Use $('#someId').trigger('change'); to fire the event manually.
See the documentation for trigger().

When the combo/list value is changed with script the onchange is not supposed to fire. I don't know how Watij is doing that, but this is one case.
Second thing is that Watij is working with IE (as long as wikipedia is rght) and IE is putting a system control in place of Your list or combo and it might break something too. Try upgrading to IE8 which has a tiny bit better realisation of form components (eg. select finally supports "disabled" attribute in options after 10 years)
You might also be interested in a normal application GUI testing apps and use them on a browser with the webapp. Record a macro and check screenshots.