Hi I would like to know if its possible to do something similar to the example shown below.
// Script A
$('.submitButton').click(function() {
if (not valid) {
$(this).attr("disabled", "disabled");
}
});
// Script B
$('.submitButton').click(function() {
// Do something else here
});
I would like to know whether you can actually stop the click event in Script B if not valid in Script A. The reason for the two events being separate is due to the fact that Script A will be used as a sort of a plugin module which will be inserted at the header of the page.
Yes, you can call $(this).stopPropagation(); and then check for event.isPropagationStopped() in Script B.
read more # http://api.jquery.com/event.stopPropagation/
use unbind. It will not fire the event again unless you bind it again
Would this work for you?
$(".submitButton").click(function(event){
event.preventDefault();
});
Related
I am using following code on my page which I am loading in ajax.
$(document).ready(function() {
$('#button_id').click(function() {
//Do Something
});
});
Now When I click on the button action happens multiple times. I know that its happening because I am loading the ajax page multiple times.
Please help me solve this.
You can use .off() to remove existing listeners:
$(function() {
$('#button_id').off('click').click(function() {
//Do Something
});
});
If I am wrong about your implementation I apologize. Your problem may exist because the binding is created on first page load and then on subsequent ajax loads with new scripts being inserted and creating duplicate bindings. You should prevent any bindings from being generated on ajax loads to prevent duplicate bindings unless you are good with cleanup.
If the button you are clicking on exists in the ajax loaded area then you should use delegation to ensure that the click handlers still work.
For example:
$( "body" ).on( "click", "#button_id", function() {
//do something
});
This will add a binding to the body element, but more specifically to the id #button_id. A click event on the button will propagate and bubble up to the body element (or whatever parent element you choose).
This makes it so that dynamic elements can be inserted in the DOM and only one event handler is needed to listen for it.
No need for .on() or .off() calls for individual ajax loads. This allows your bindings to be much cleaner.
Of course, if your button is not likely to exist on the page all the time then it would not be a good idea to keep extra bindings. Only create these types of binding if they are always needed to prevent optimization issues.
A cleaner solution would be to remove that code from the ajax loaded HTML and use one single event handler in the master page
I guess your problem is the event is firing many times.
To fire only once try this:
$(document).ready(function() {
$('#button_id').on("click",function(e) {
e.preventDefault(); // This prevents the default non-js action (very used for anchors without links or hashes)
e.stopPropagation(); // Prevent the bubling of the event and spread more times
//Do Something
});
});
If doesn't work with e.stopPropagation(); try with e.stopInmediatePropagation();
Adding documentation for the last method I suggested. It could solve your problem.
http://api.jquery.com/event.stopimmediatepropagation/
Is there any way we can intercept the html form's onsubmit event?
In my web application, there are several screens containing forms etc. The issue we are facing is when the user presses any button multiple times, the server gets overloaded with same requests.
Some of the forms have event handlers already attached to them(like onSubmit, button.onClick etc).
One way can be to "inject" my button disable code by going through all the screens.
But what I am looking for is a generic solution which can be applied to all the screens by just including the script where the function is written.
I know I can setup callback using jQuery (capturing onSubmit for form), but in the issue in this case is if any screen has a onSubmit registered already, it may not get called.
Any help in this regard appreciated!
I think this piece of code is a good place to start. It should be placed in separate file and included where you want to use it (if you appear to have global list of scripts - its a good place for it)
var suppressed_items = [];
function allowOnlyOne(item,e){
if (jQuery.inArray(item, suppressed_items)==-1){
//hi little item, I haven't saw you before, please go on... but I remember you
suppressed_items.push(item);
return true;
}
else{
//Hey, you have been submitted already, stay where you are!
return false; //or e.preventDefault(), it's a matter of faith :)
}
}
jQuery(document).ready(function(){
//don't worry, it won't replace your `ready` handlers, but just append new handler
jQuery("from").submit(function(e){
return allowOnlyOne(jQuery(this),e);
});
});
You can use the allowOnlyOne function with any item you wish. So, for example to allow single click on all hyperlinks, inside that ready handler add:
jQuery("a").click(e){
return allowOnlyOne(jQuery(this),e);
}
I hope you get the basic idea: catch the event, get the ID of the element that trigger it, fed it to AllowOnlyOne along with event.
Of course you can wrap it all around into self-executing closure to achieve incapsulation and so on...
If you already have jQuery I suggest you use it... All you need to do is make sure is that your form's onsubmit do not have a "return false" or else it can block jQuery's on submit.
Here's what you need to do:
Remove any return false from your form's onsubmit (if any). Don't worry we'll take care of this later in jQuery.
Add a class to your forms... something like "disableOnSubmit". Example:
<form action="something" onsubmit="yourExistingCode" class="disableOnClick">
</form>
OR
<form action="something" onsubmit="yourExistingCode" class="someOtherClass disableOnClick">
</form>
Implement a code similar to:
<script type="text/javascript">
$(document).ready(function(){
$('form.disableOnClick').submit(function(e){
// preventDefault() does the same as "return false;". It
// will not submit the form. If you're not using return false
// and want the form to be submitted remove the line below
e.preventDefault();
// Now diable any submit button
$('input[type=submit], button[type=submit]').attr('disabled, 'disabled');
});
});
</script>
The goal is to disable all the links, when one is clicked, and then disable all the links until the server sends an undisable command (using a similar method that would be used to disable).
So, since all the links are in one containing div, I figure I could just temporarily disable that.
How would I go about doing that?
If you just want to disable the default link behaviour, you can use a combination of delegate and event.preventDefault:
$('#container').delegate('a', 'click', function(e) {
if (linksDisabled) {
e.preventDefault();
}
});
You can then set linksDisabled (in a parent scope) to true or false in your other event handlers as appropriate.
If these links are doing Javascripty things, it's a bit trickier. It would probably be easiest to put the if (linksDisabled) check in each event handler.
Try this:
$("#YOUR_DIV a").click(function(){
return false;
})
From my experience I know three different ways to execute a JavaScript function when a user clicks on a link
Use the onclick attribute on the link
click me
Use the href on the link
click me
Don't touch the link, do everything in js
click me
(in the JavaScript we will stop the default event, and call the function)
Which one is better? What are the advantages and disadvantages?
EDIT deleted the "javascript:" on onclick
Unobtrusive Javascript (your third example) with graceful degredation is the best choice.
It is always good to have a link in the href attribute so as to support users who have disabled JavaScript on their browsers.
click me
None of the above. Use the click event (assigned either as an attribute or via script if you prefer) and have a real URL as a fallback:
click me
or HTML:
click me
Script:
document.getElementById("myLink").onclick = function() {
myfunction();
return false;
};
Also, don't prefix code in event handler attributes with javascript:. It's incorrect and only doesn't throw an error by coincidence (which is that in JavaScript, javascript: creates a label called javascript).
Or alternatively, use jQuery
$(function() {
$('[id$=myLinkID]').click(function(e) {
myFunction();
});
});
I want to simulate a click on any link on a page using JavaScript. If that link has some function binded to its 'onclick' event (by any other JS I don't have any control over), then that function must be called otherwise the link should behave in the normal manner and open a new page.
I am not sure that just checking the value of the 'onclick' handler would suffice. I want to build this so that it works on any link element.
I have no control over what function maybe binded to the onclick event of the link using whichever JS library (not necessarily jQuery) or by simply using JavaScript.
EDIT: With the help of the answers below, it looks like it is possible to check for event handlers attached using jQuery or using the onclick attribute. How do I check for event handlers attached using addEventListener / any other JS library so that it is foolproof?
You can use the the click function to trigger the click event on the selected element.
Example:
$( 'selector for your link' ).click ();
You can learn about various selectors in jQuery's documentation.
EDIT: like the commenters below have said; this only works on events attached with jQuery, inline or in the style of "element.onclick". It does not work with addEventListener, and it will not follow the link if no event handlers are defined.
You could solve this with something like this:
var linkEl = $( 'link selector' );
if ( linkEl.attr ( 'onclick' ) === undefined ) {
document.location = linkEl.attr ( 'href' );
} else {
linkEl.click ();
}
Don't know about addEventListener though.
Why not just the good ol' javascript?
$('#element')[0].click()
Just
$("#your_item").trigger("click");
using .trigger() you can simulate many type of events, just passing it as the parameter.
Easy! Just use jQuery's click function:
$("#theElement").click();
Try this
function submitRequest(buttonId) {
if (document.getElementById(buttonId) == null
|| document.getElementById(buttonId) == undefined) {
return;
}
if (document.getElementById(buttonId).dispatchEvent) {
var e = document.createEvent("MouseEvents");
e.initEvent("click", true, true);
document.getElementById(buttonId).dispatchEvent(e);
} else {
document.getElementById(buttonId).click();
}
}
and you can use it like
submitRequest("target-element-id");
At first see this question to see how you can find if a link has a jQuery handler assigned to it.
Next use:
$("a").attr("onclick")
to see if there is a javascript event assigned to it.
If any of the above is true, then call the click method. If not, get the link:
$("a").attr("href")
and follow it.
I am afraid I don't know what to do if addEventListener is used to add an event handler. If you are in charge of the full page source, use only jQuery event handlers.
All this might not help say when you use rails remote form button to simulate click to. I tried to port nice event simulation from prototype here: my snippets. Just did it and it works for me.