I am newbie to jQuery and javascript. In my application I have a list of users. When a particular user is clicked from the list, a div element is replaced with details about the user dynamically. When another user is clicked, again I replace the same div element with this user details. So at a time only one user details can be seen.
I use jquery, so my code to the above description looks like.
$('table#moderate_users tr').click(function() {
$.get('/moderate/user/'+uid, function(data){ $('div.user_info').html(data);
});
});
This works perfect and the content is inserted dynamically.
I have a dropdown(html select tag) in the dynamically added content. So I get the dropdown only when i click on a user from the list and it changes repectively when I click on another user. I wanted to find the value of the select tag using jquery whenever it is changed. So I wrote
$('select#assign_role').change(function(){
alert(this.val());
});
Since this dropdown is added after document.ready, adding this script inside document.ready function never worked. I also tried to insert the above script along the with the user details which is dynamically added.For my surprise this script is not inserted into the document at all, while the rest of the HTML content are inserted perfect. I am not aware if i can add insert javascript after the document has loaded. I am not aware how i could use jQuery to find out the value of the select tag which is added dynamically.
Thanks.
you want jQuery's "live" functionality:
$('select#assign_role').live('change',function(){
alert($(this).val());
});
also notice I changed alert(this.val()); to alert($(this).val()); considering that this inside a jQuery event handler references the actual dom element, not a jQuery object.
From the looks of your code, it seems that you are inserting a chunk of HTML into that div. So even if you wire your event to the dropdown after the page load, it will not work, since all of your event binding will be ignored when you insert new HTML code into div.
Try moving your code inside the function that inserts HTML. Something like this:
$('table#moderate_users tr').click(function() {
$.get('/moderate/user/'+uid, function(data){
$('div.user_info').html(data);
$('select#assign_role').change(function(){
alert(this.val());
});
});
});
On IE the live function doesn't work for onchange on <select> elements.
http://www.neeraj.name/blog/articles/882-how-live-method-works-in-jquery-why-it-does-not-work-in-some-cases-when-to-use-livequery
You will need to either add the select then do a setTimeout and then bind with the jquery.bind type of functionality, or, what I have done, is when you create the element then just set the onchange event handler there directly.
If you don't need to support IE then the live function works great.
Related
For each checkbox on the web page, I replace it with a slider that I borrowed from jsfiddle.net/gnQUe/170/
This is done by going through the elements when the document is loaded.
Now the problem is that when more content is loaded via ajax, the new checkboxes are not transformed.
To solve the problem, I used AjaxComplete event to go through all the elements again and replace the checkboxes with sliders.
Now the problem happens that elements that were already replaced, get two sliders. To avoid that I check if the checkbox is hidden and next element is div of class "slider-frame", then don't process the re-process the element.
But I have a lot of other such controls as well, and I am presume I am not the only one that has this problem. Is there another easy way around it?
There exists jQuery live/on( http://api.jquery.com/on/ ) event but it requires an event as an argument? whereas I would like to change the look of my controls when they are rendered.
Another example of the same problem is to extend some controls that are loaded via ajax with jQuerys autocomplete plugin.
Is there a better way to accomplish this other than changing some attributes on the element.
To summarize, on document load I would like to process every element in DOM, but when more elements are loaded via ajax then I want to change only the new elements.
I would assume that when the element's are transformed into a slider, a class is added to them. So just add a not clause.
$(".MySelector").not(".SomeClassThatSliderAddsToElement").slider({});
So in the case of your code do something like this
$('.slider-button').not(".sliderloaded").addClass("sliderloaded").toggle(function(){
$(this).addClass('on').html('YES');
$('#slider').val(true);
},function(){
$(this).removeClass('on').html('NO');
$('#slider').val(false);
});
Since you said you do not want to add anything else, how about you change the toggle function to click.
$(document).on("click", ".slider-button", function(){
var elem = $(this);
elem.toggleClass("on");
var state = elem.hasClass("on");
elem.text(state?"YES":"NO");
elem.parent().next().val(state);
});
Running fiddle: http://jsfiddle.net/d9uFs/
I have a form that I am trying to alter with jQuery. Basically, my form has two elements and I need to change the value of the first option in each of them. However, there is an "add more" option that uses AJAX to dynamically generate another element that also needs changed. This add more button can be clicked an unlimited amount of times.
Right now I have this:
$(document).ready(function(){
$("#myname-0-field option:first").val("None");
$("#myname-1-field option:first").val("None");
});
This works fine, but once the "add more" button is clicked, I have more elements called "#myname-2-field", "#myname-3-field", "#myname-4-field" etc. These obviously aren't affected by adding another line into my jQuery as the document has already loaded when they are added.
So the real question is, can someone point me in the right direction of writing a function that can react when the new element is added and change it. If possible, I'm also looking for the function to be aware and look for "#myname-X-field option:first" for tidyness.
use live() function
Then using each function set value
From the jQuery API look live function
Maybe you could add class to your element, so that finding particular element would be easier and it would not add event to other similar elements.
In the example I have a Li with class
$('li.myClass').live('click', function() {
$(this).val(); // this is the getter for clicked value
$(this).val("some_value_here"); // this is the setter for clicked value
});
Now you can add more elements (that has myClass class) and it will have a click event.
Btw. if you know that all elements are inside some container (div for example) then you can write more efficient jQuery using delegate.
$('#container_id').delegate('li.myClass', 'click', function () {
});
This is more efficient because it looks your new elements only under "containter" not from the whole DOM structure.
Hi i am using Ajax to get a SELECT tag. I mean, if i click on a button it will generate a SELECT tag inside HTML, i have different outputs for different options of select.
I need an onclick event on that SELECT tag, i tried using JQuery
$('#id').click(function() {
alert('test');
});
Its not working. Can anybody help, please
Because the select tag is dynamically added to the HTML after the event was set, the event is not set on the select tag.
A simple solution is to use live() here:
$('#id').live('click', function() {
alert('test');
});
as you are dynically generating html use live instead of click
$('#id').live('click', function() {
// Live handler called.
});
Make sure
you have jQuery script file is inserted in your html page,
you have assigned id id to one and only one item on your page,
you give us a link to see your page if nothing else helps. :)
live is now deprecated. Use on instead.
I have web layout, which can contains several links on it. Those links are dynamically created, using AJAX functions. And it works ok.
But, I don't know how can I work with those "dynamically created links" (ie. how to call some JS or jQuery function if I click on them). I guess that browser can not recognize them, since there are created after page is loaded.
Is there some function, that can "re-render" my page and elements on it?
Tnx in adv on your help!
You can use the 2 following methods jQuery provides:
The first one, is the .live() method, and the other is the .delegate() method.
The usage of the first one is very simple:
$(document).ready(function() {
$("#dynamicElement").live("click", function() {
//do something
});
}
As you can see, the first argument is the event you want to bind, and the second is a function which handles the event. The way this works is not exactly like a "re-rendering". The common way to do this ( $("#dynamicElement").click(...) or $("#dynamicElement").bind("click", ...) ) works by attaching the event handler of a determinate event to the DOM Element when the DOM has properly loaded ($(document).ready(...) ). Now, obviously, this won't work with dynamically generated elements, because they're not present when the DOM first loads.
The way .live() works is, instead of attaching the vent handler to the DOM Element itself, it attaches it with the document element, taking advantage of the bubbling-up property of JS & DOM (When you click the dynamically generated element and no event handler is attached, it keeps looking to the top until it finds one).
Sounds pretty neat, right? But there's a little technical issue with this method, as I said, it attaches the event handler to the top of the DOM, so when you click the element, your browser has to transverse all over the DOM tree, until it finds the proper event handler. Process which is very inefficient, by the way. And here's where appears the .delegate() method.
Let's assume the following HTML estructure:
<html>
<head>
...
</head>
<body>
<div id="links-container">
<!-- Here's where the dynamically generated content will be -->
</div>
</body>
</html>
So, with the .delegate() method, instead of binding the event handler to the top of the DOM, you just could attach it to a parent DOM Element. A DOM Element you're sure it's going to be somewhere up of the dynamically generated content in the DOM Tree. The closer to them, the better this will work. So, this should do the magic:
$(document).ready(function() {
$("#links-container").delegate("#dynamicElement", "click", function() {
//do something
});
}
This was kind of a long answer, but I like to explain the theory behind it haha.
EDIT: You should correct your markup, it's invalid because: 1) The anchors does not allow the use of a value attribute, and 2) You can't have 2 or more tags with the same ID. Try this:
<a class="removeLineItem" id="delete-1">Delete</a>
<a class="removeLineItem" id="delete-2">Delete</a>
<a class="removeLineItem" id="delete-3">Delete</a>
And to determine which one of the anchors was clicked
$(document).ready(function() {
$("#links-container").delegate(".removeLineItem", "click", function() {
var anchorClicked = $(this).attr("id"),
valueClicked = anchorClicked.split("-")[1];
});
}
With that code, you will have stored in the anchorClicked variable the id of the link clicked, and in the valueClicked the number associated to the anchor.
In your page initialization code, you can set up handlers like this:
$(function() {
$('#myForm input.needsHandler').live('click', function(ev) {
// .. handle the click event
});
});
You just need to be able to identify the input elements by class or something.
How are these links dynamically created? You can use use the correct selector, given that they are using the same class name or resides in the same tag, etc.
consider the html form
<form>
<input type="text" id="id" name="id"/>
<input type="button" id="check" name="check value="check"/>
</form>
jquery script
$('#check).click(function() {
if($('#id).val() == '') {
alert('load the data!!!!);
}
});
here on clicking the button the script check the value of the textbox id to be null. if its null it will return an alert message....
i thin this is the solution you are looking for.....
have a nice day..
Noramlly , the browser process response HTML and add it to DOM tree , but sometimes , current defined events just not work , simply reinitialize the event when u call the ajax request ..
All you need to do to work with dynamically created elements is create identifiers you can locate them with. Try the following code in console of Firebug or the developer tools for Chrome or IE.
$(".everyonelovesstackoverflow").html('<a id="l1" href="http://www.google.com">google</a> <a id="l2" href="http://www.yahoo.com">yahoo</a>');
$("#l1").click(function(){alert("google");});
$("#l2").click(function(){alert("yahoo");});
You should now have two links where the ad normally is that were dynamically created, and than had an onclick handler added to bring up an alert (I didn't block default behaviour, so it will cause you to leave the page.)
jQuery's .live will allow you to automatically add handlers to newly created element.
If your links are coming in via AJAX, you can set the onclick attributes on the server. Just output the links into the AJAX like this:
Holy crap I'm a link
The return false makes sure the link doesn't reload the page.
Hope this helps!
I have created a dynamic list picker script using Jquery 1.3 and PHP that sends a JSON AJAX request and returns a list of items to choose from. The AJAX call works perfectly returning an array of items that I use Jquery to append them as an unordered list to an empty container DIV. That portion of the process works as expected.
The problem comes from the fact that from that list of items, I'm drawing them as links whose clicks are handled by a rel attribute. Here's an example:
<a rel="itemPick" id="5|2" href="#">This is the link</a>
The JQUERY handler looks like:
$('a[rel=itemPick]').click(function () {
code here...
});
These links and click handlers work fine when the page loads, but when they are appended to the container DIV, the click event does not get picked up. I don't want to have to refresh the entire HTML page again, so is there something I need to do in addition to append() to get JQUERY to recognize the newly added links?
When you use the jQuery.click method, it's looking for all of the "a" elements that currently exist on the page. Then, when you add a new "a" element, it has no knowledge of that click event handler.
So, there's a new event model in jQuery that allows you to bind functions to all current and future elements called Live Events. You can use Live Events the same way that you use normal event binding, but they will work for all future elements specified. So, you can simply switch your binding logic to:
$('a[rel=itemPick]').live('click', function () {
//code here...
})
$('a[rel=itemPick]').live("click", function (){ code here... });
Do you bind the event after adding the links?