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Overwrite listener without handler reference, is it ok to access the (possibly private) events property on a Ext.data.store?

I'm working on replacing an Ext.data.Store load event handler.
The variable me is different every time within the code block but me.store is the same (obtained via StoreManager.lookup). I want the store event listener to update the various me references. Best way i could find was to add another listener (and delete the old one since i don't need it anymore)
I haven't been able to use un / removeListener i.e. it had not effect.
I've found that i could replace the it by accesing the me.store.events and popping the listener from the load event. However this feels hacky and it might make the code dependant on a specific ExtJS version (4.2) since i don't know if it's a private property or not.
Also me.store.hasListeners['load'] doesn't get notified so it only helps because it removes the actual listener but not in the intended manner. The docs don't mention it, but i'm wondering if it may be an inherited property which can be accessed freely.
Are there any alterntives to the working approach i've come to? Can i remove all event handlers for an event without having a reference to the handler? Or is there a simpler approach i'm missing?
var me = this; // an enriched Ext.form.FormPanel, different every time code runs
me.store //obtained via StoreManger.lookup - so the same every time
me.storeLoaded = function (store, records,successful, opts) {
// some code to select a record from records and use it
me.loadRecord(record);
}
};
if (!me.store.hasListener('load')) {
me.store.on('load', me.storeLoaded);
} else{
//tried this, but it doesn't remove it, probably because me.storeLoaded is different each time (parentForm is different)
me.store.un('load', me.storeLoaded);
//this feels hacky, i couldn't find out if events is a private property
if (me.store.events && me.store.events['load']){
me.store.events['load'].listeners.pop()
}
me.store.on('load', me.storeLoaded);
}

The easiest way to implement adding/removing listeners is using the destroyable parameter as described in the addListener function. That way, you can always be sure which one is removed.
Example:
setActive:function(cmp) {
cmp.myActiveListeners = cmp.eventStore.on({
destroyable: true,
load:cmp.refreshStores,
filterchange:cmp.refreshStores,
scope:cmp
});
},
setInactive:function(cmp) {
Ext.destroy(cmp.myActiveListeners);
},
I cannot recommend to blindly remove ALL listeners, since they may be added by other components (e.g. combobox) that you add later. To track down these bugs will grow you quite some gray hairs.

I was able to find an answer in this article ExtJS overwrite listener:
Sometimes you need to overwrite an event listener in ExtJS. Usually
listeners are registered like this myStore.on('load',
this.myFunction, this); then to remove our previously registered
listener, all we have to do is call un (which is an alias for
removeListener): myStore.un('load', this.myFunction, this);
But, what happens when you don't know what function is registered?
Sometimes you will not have a reference to the original function that
was registered. This situation may arise if there is code that exists
in a different flow or may even come as a package! If that is true,
the you may not be able to get a reference to the javascript function
or edit the existing code. In this case, we will have to look at all
of the functions that are registered for this event. We can then
remove the listeners just for a certain event by calling
clearListeners.
clearListeners was the method i was looking for.
It would seem he uses the events property so i assume it is a valid use. It could be translated in my case to:
me.store.events.load.clearListeners()
However since i will only be using the load event on this particular store, i will simply call on them all.
me.store.clearListeners()
Thanks to Alexander, by suggesting not to remove all listeners that actually helped me find the article. However i will stil go with his solution, even if it polutes the store object because i like it better than clearing all listeners on a store, even if only for a specific event.

Conditionally attaching jQuery plugin functions to elements on the site

I want to attach a jQuery plugin function to an element on my site that exists only on one page. Currently, I'm using this conditional to prevent triggering the limiter function and throwing an error when there is no #advertiser_co_desc in view.
jQuery(document).ready(function($) {
var elem = $('#charNum');
if ($('#advertiser_co_desc').length) {
$('#advertiser_co_desc').limiter(180, elem);
}
});
On my website #advertiser_co_desc is present only on one page.
My solution does the job, but my qualm stems from the fact that the jQuery plugin code as well as the plugin function call presented above (they are both in the same file) get fetched by the browser and the condition is continuously evaluated regardless of whether a user ever gets to a page where #advertiser_co_desc exists.
Is the method I'm using optimal, or is there a better way to attach this particular JS only to the page where '#advertiser_co_desc` exists? Naturally, I wan to avoid adding my scripts in the same file with the PHP code.

Or you can wrap the plugin method as,
var _limiter = $.fn.limiter;
$.fn.limiter = function(limit, element) { // provide complete argmuments
if(this.length) {
_limiter.call(limit, element);
}
};
Make sure that plugin is loaded before this statements.

The best and optimal way to check existence of an element by jquery, is $('#advertiser_co_desc').length that you have used already. So no need to change your code.

Is there an equivilant of phpinfo for jquery?

server side background, getting deeper and deeper into client side.
I've got a site with a lot of legacy that I'm new to, and I'm just trying to get a handle on how things are working/what's available.
Is there a way to have jquery tell me(for a page/pages) all its current info and any plugins it can/is use/ing, similar to what phpinfo does?

Some proof of concept how you can get names for all plugins
var plugins = (function() {
var plugins = [];
for(var plugin in jQuery.fn) {
plugins.push(plugin)
}
return plugins;
}());
var filterValue = ['constructor', 'init', 'add', 'parents'] // // you must add all standard methods here
filterValue.forEach(function(value) {
var position = function(value) {
return plugins.indexOf(value);
}
while(position(value) >= 0) {
plugins.splice(position(value), 1)
}
})
console.log(plugins)

You can use the following for jQuery
console.log( jQuery.fn.jquery );

To answer your question directly, No jQuery does not have a mechanism that lists installed plug-ins.
jQuery does not keep such a registry of installed plugins. The jQuery plugin mechanism is to just add a method to the jQuery prototype (right along-side all the other jQuery methods). So, there's no separate list of which methods have been added by some outside agent (e.g. a plug-in). In addition, there's no one-to-one correspondence between methods and a particular plug-in as a single plug-in could add multiple methods.
It would be possible to create a master list (for any specific jQuery version) of what methods are there by default and then enumerate a jQuery object to find out which methods have been added since then, but you'd have to create that master list ahead of time and store it or create the master list immediately after jQuery was loaded before any plug-ins were loaded.
You can always test to see if any specific jQuery plug-in is loaded by just checking to see if any of its signature methods are available on a jQuery object.
So, if you really just wanted to know which of 10 plugins happen to be available in any given page, you could write a quick function that would test for each of the 10 plugins (by looking for the existence of known methods in those plugins) and would return a list of the ones installed, but this has to be done with specific knowledge of each plugin as there is no "generic plugin identification mechanism" since a plug-in is nothing more than a piece of code that adds methods to the jQuery prototype. It doesn't actually have any identity of its own.

Is there a way to trigger an event when inserting html?

It's for a backbone application,
I'm using Jquery html() function to insert my views templates into the layout everywhere, and I would like to be able to trigger an event each time the html() function of jQuery is called to check the html of the page.
Is there a way to do that ?
( Like App.on('html', blablabla...); )
Thank you !

As Marc B suggested DOM MutationEvents is available on some browsers (not many). By default jQuery does not fire any event when using html, but you can define your own behaviour for this, for example:
(function($) {
var html_ref = $.fn.html;
$.fn.extend({
html : function() {
$(document).trigger( 'html_change' );
return html_ref.apply(this, arguments);
}
});
})($);
It should work, didn't test it though. You can use the same with .text method. Now you can simply use:
$(document).bind( 'html_change', function() {
// Hurray! Html changed!
});
That's the idea, use it as you wish.

AFAIK, the jQuery html() method doesn't fire any subscribable events per se, but you could probably roll your own implementation of a simple Observer pattern. I use this across a large number of projects and it provides a great, clean, lightweight way to encapsulate arbitrary event handling across loosely-coupled modules.
However, this is presuming that you have programmatic control over every time the html() method is called - if not, then this would be more difficult, as there is no callback function to hook into.

Initializing jQuery.load'ed elements

I'm loading part of my webpage using AJAX, in particular jQuery.load(). With this the usual jQuery pattern
$('.classname').click(...) // Handler
// or, working with bootstrap
$("a[rel=tooltip]").tooltip() // Function
or similar obviously don't work any more, because they are called only when the page is loaded. I realize there is jQuery.on for the first example, but how would I implement the second?
Is there a simple (builtin) way to also apply these to jQuery.loaded stuff, or do I have to work around it myself? Seems like a problem a lot of people should be having.

You have to work around it yourself; but you can easily to this by calling $("a[rel=tooltip]").tooltip() in the callback for load():
$('#blah').load('/somewhere.html', function () {
$('#blah').find('a[rel="tooltip"]').tooltip();
});
Be sure to restrict the tooltip() call to only newly loaded elements, or you'll end up initializing tooltip multiple times per element (which may result in weird behaviour).
To avoid duplicating code you just need to define a helper function;
function initTooltip(root) {
return $(root || document).find('a[rel="tooltip"]').tooltip();
}
Which allows you to init tooltip. The parameter is optional, and lets you restrict initialization to only descendants of the provided element, e.g.:
jQuery(document).ready(function ($) {
initTooltip(); // equivilant to initTooltip(document);
$('#blah').load('/somewhere.html', function () {
initTooltip('#blah');
});
});