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JavaScript does not work well inside a loaded content in a DIV

I am creating an application with Symfony2, where I have a main menu of options depending on the option selected dynamically opens a tab at a lower div with the content for that option. Content is loaded with load() of Jquery in the container div.You can see in the picture below:
The first problem was that in the HTML loaded in each tab could not use the js file initially loaded in the index.html, as you can see in this example you should check out a notice when we click the content of each tab, but does nothing .
The solution to this problem was included in each HTML code to load the appropriate script, and it worked properly. But to do it this way, if two HTML carry the same js, when one of the contents some event runs is repetite many times as tabs we have created, that is, if I open two different options (each in its own tab both charge the same js) by clicking on the first event associated performed twice, whereas if I do it in the second only done once. In short, whenever a function of a js used, is repeated as many times as there are dynamically loaded on the tabs.
And I tried event.preventDefault();orevent.stopPropagation(); and it does not solve the problem.
Would it be okay that it js is included twice in the overall structure of HTML? (Included in the initial head and then the container div)

Dynamically loading HTML + JavaScript is not the best approach for this case. I suggest that you use some JavaScript SPA framework, like AngularJS or ReactJS. Both are very big and well supported projects, so you can find tons of documentation and tutorials. You'll most likely end up using Symfony only as a RESTful service and Angular/React taking care of the rest (template loading, sending request to server, etc). Also, js frameworks will take care of deep linking and in the end you'll have a better working, easier to maintain application.
It is a bit more work initially, especially until you bootstrap the application, but then it gets easier to maintain and implement new functionality, so it pays off in the end. With your current approach you soon will find yourself in a big mess full of 100s of templates, js callbacks, inclusions, etc. I'm saying this from a personal experience!

Well...
Jquery works like this: when you attach an event to html, if the html does not exist, the event is attached to nothing. If the element exists then the event is correctly attached. It attaches only to existing elements when the on function is execute. That is a correct behaviour. In the past it used to exist a .live method that did exactly what you want: you attached an event and if you create the element after the attachment, the new element also contained the event.
Adding the js twice is not the solution. As you said after a click the button will be executed twice.
Why do not attach the events after loading the content? If you load it in the page start you can do in the main file:
$(function(){ // will force to execute the on method after all the page is loaded.
$('.submenu .button').on ('click', function (){
...
});
});
If you load the menu by ajax, in the callback and after adding the html menu to the main you must use the code I wrote above.

Adding a script to a DOM object

I want to add a script that applies to a DOM object of a certain type right after it is loaded/rendered. This type of object always comes together with the javascript script, and I want to put them together within some tag. Is it right to do it as below? If so, I suspect span is not the best tag to be used here because it may interact with the way the element inside will be displayed. What tag should I use?
<span>
<div>the dom object to be modified by the script</div>
<script>theJavascriptFunctionThatModifiesTheDomObject()</script>
</span>

I doubt this is the best way to load your script just after a particular element has been loaded by DOM due to these reasons:-
It makes your page load slower.
User will see your complete page in a discrete way.
Instead you should do this:-
Specify a selector to your element.
Include your single javascript code at the end of body.
Update DOM elements using that script.
EDIT:
Solution1: Append your JS at the end of body so that it has access to all the DOM elements.
Since you are injecting the element in DOM using ajax, you can define a success handler for XHR object which will modify your element in DOM.
Solution2: You can define a separate method in your JS and bind this method on some event. In your HTML markup define a data-event attribute and in your success handler append the element to DOM, extract the data-event using jquery data method and trigger that event.
Atleast it will keep you markup far away from scripting logic.
Some useful Links:
Best practices for speeding up your website - yahoo
Why we should load scripts at end - SO Link

The problem here is the script tag does not know where it is located in the DOM. It would be better to do something like add a class to the element[s] you want to alter. On DOM ready, you look up the element[s] and do your magic.

I would avoid this approach; scripts block the page loading
– so if you did this after several dom elements the page would run slow (or not at all if errors were found)
Try using jquery onready - example here : http://api.jquery.com/ready/
And scripts [usually] need to go on the bottom of the page to allow the page to load first
…there are exceptions to this rule such as the well known modernizer script library that needs to go first so it can evaluate the dom as it loads

Load external html file to div and use its js functions

I have some div:
<div id='dialog'></div>
Now I want to load into this div an external html file and use its js functions.
I know I can load it using jQuery.Load() and it works fine, the problem is that I want to use the html js functions.
The main problem is that I have several divs which I load this html file into them and I want that when I'm activating js function it will only work on the specific div.

Pass parameter to view that you are loading that will indicate container of the loaded view:
jQuery.Load(url, { containerId: 'dialog' })

I remember I had the problem back when jQuery1.4 was issued. In that version, .load() suddendly began stripping out the js when a target container was specified.
What I did at that time :
separate html and js in different files (let's say myhtml.html and myjs.js ), or views
have my js file act as a js module, with a public entry point function (say initContent) taking a jQuery element as a parameter
have an invisible link in myhtml.html, namely
after loading myhtml.html into my target div, search for $('a.dynamicJs') in my target div to extract js url, and entry point function from the href
if the js had not previously been loaded, dynamically load the js into the page trhough an ajax call
dynamically call the entry point function with the target div as parameter
This also worked with css.
It required some time to tweak it on all navigators (limited number of css sections on IE, different way to dynamically call a function), and I ended with much more code I expected in the first place. It also required a lot of refactoring of my html/js modules (but I must confess I ended having a code that was really cleaner)
I'm sure there are frameworks that handle this kind of situation way better by now. But this is what I came up with at that time.
Hope this will help

Preventing CSS of Jquery Dialog content from being applied to main window

In my web application, I have written a cross-domain ajax call which is fetching an HTML page from a different domain. This newly fetched page is being rendered in a jQuery dialog using the following code $('#previewDialog').html(response).dialog('open');
This renders the response properly in the dialog. However, the response (HTML page) also has some CSS styles in it. These styles (generally BODY, INPUT etc) are getting applied to my main window (parent page) and distorting the complete view of the page.
When the dialog with the HTML page opens, the view of the parent page is completely distorted because of the CSS used in the HTML page (response of AJAX call) which gets applied to all the components. And when I close the Dialog, the parent page gets back into shape.
Is there anyway, by which I can prevent the CSS of the HTML page which is being displayed in dialog, not get applied to my parent page?

Trivial answer: have everything from the page that you pull in be wrapped in a div with a class not used elsewhere. modify the .css for that page so that it only applies to elements within a div of that class.
Edit: If you cannot control the css of the origin page, things become somewhat more complicated. your problem, though, is that you're injecting the HTML (including the css link) directly into your page. Instead, try the following:
Grab the HTML for the other page. Place it into a div off to the side that you're not using for anything else using the html() command.
Go into that div using the jquery DOM commands. Grab the portion of the page inside of the troublesome links, and pull it over to the $('#previewDialog') location. Destroy the contents of the working space div. If there is javascript or css that you need to preserve, have it entered (modified, if necessary - like with div wrappers) elsewhere in the page.
Now, this only works if the pages that you're being fed don't have their css or javascript changing with any frequency.
An alternate version of the same thing - while you have it as a response (a string format) use string manipulation tools to excise the css reference, rather than using DOM commands to pull what you need out of it.
More complicated/difficult version of the same thing (though somewhat more robust): Use string commands to slice out the css references (as with the alternate version) and then make another call using that css reference to acquire the .css file. Use string commands on the .css file to add in the div-wrapper limits as initially described, then insert it elsewhere on the page as an internal style sheet.

Trigger an Event in javascript before objects finish to load

I was trying to write a global JavaScriptfunction which overrides any HTML object (img, iframe, links and so on) before it being loaded by the page. The purpose of the overiding action was to to change the SRC and HREF of these objects using the DOM to any other link.
Unfortunately I didn't find any solution to that without firstly loading the object and only then changing it by the onload event.
My second option was to change the SRC and HREF by matching these attributes with a regular expression and replacing the resultant values. I prefer not to do so because it's slow and consumes a lot of time.
I would be glad if someone can share with his/her experience and help me solve this out.

JavaScript only works within the DOM.
You could however, load the page via AJAX, get the content and do any string manipulation on it.

If you are trying to modify items that exist in the static HTML of the page, you cannot modify them with javascript until they are successfully loaded by the browser. There is no way to modify them before that. They may or may not be visible to the viewer before you have a chance to modify them.
To solve this issue, there are a couple of options.
Put CSS style rules in the page that causes all items that you want to modify to initially be hidden and then your javascript can modify them and then show them so they will not be seen before your modification.
Don't put the items that you want to modify in the static part of your HTML page. You can either create them programmatically with javascript and insert them into the page or you can load them via ajax, modify them after loading them via ajax and then insert them into the page.
For both of these scenarios, you will have to devise a fallback plan if javascript is not enabled.