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Stop onclick method running with jQuery

I have a button similar to below
<button id="uniqueId" onclick="runMethod(this)">Submit</button>
What I'm trying to do is stop the runMethod from running, until after I've done a check of my own. I've tried using the stopImmediatePropagation function, but this doesn't seem to have worked. Here's my jQuery:
$j(document).on('click', '#uniqueId', function(event) {
event.stopImmediatePropagation();
if(condition == true) {
// continue...
} else {
return false;
}
return false;
});
Note: runMethod basically validates the form, then triggers a submit.

What you want to do, especially in the way that you want to do it, requires a some sort of workaround that will always be a bit fiddly. It is a better idea to change the way the button behaves (e.g. handle the whole of the click event on the inside of the jQuery click() function or something along those lines). However I have found sort of a solution for your problem, based on the assumption that your user will first hover over the button. I am sure you can extend that functionality to the keyboard's Tab event, but maybe it will not work perfectly for mobile devices' touch input. So, bear in mind the following solution is a semi-complete workaround for your problem:
$(document).ready(function(){
var methodToRun = "runMethod(this)"; // Store the value of the onclick attribute of your button.
var condition = false; // Suppose it is enabled at first.
$('#uniqueId').attr('onclick',null);
$('#uniqueId').hover(function(){
// Check your stuff here
condition = !condition; // This will change to both true and false as your hover in and out of the button.
console.log(condition); // Log the condition's value.
if(condition == true){
$('#uniqueId').attr('onclick',methodToRun); // Enable the button's event before the click.
}
},
function(){
console.log('inactive'); // When you stop hovering over the button, it will log this.
$('#uniqueId').attr('onclick',null); // Disable the on click event.
});
});
What this does is it uses the hover event to trigger your checking logic and when the user finally clicks on the button, the button is enabled if the logic was correct, otherwise it does not do anything. Try it live on this fiddle.
P.S.: Convert $ to $j as necessary to adapt this.
P.S.2: Use the Javascript console to check how the fiddle works as it will not change anything on the page by itself.

Your problem is the submit event, just make :
$('form').on('submit', function(e) {
e.preventDefault();
});
and it works. Don't bind the button click, only the submit form. By this way, you prevent to submit the form and the button needs to be type button:
<button type="button" .....>Submit</button>
Assuming there's a form that is submitted when button is clicked.

Try adding
event.cancelBubble();
Hence your code becomes:
$j(document).on('click', '#uniqueId', function(event) {
// Don't propogate the event to the document
if (event.stopPropagation) {
event.stopPropagation(); // W3C model
} else {
event.cancelBubble = true; // IE model
}
if(condition == true) {
// continue...
} else {
return false;
}
return false;
});

Your code is mostly correct but you need to remove J:
$(document).on('click', '#uniqueId', function(event) {...
You also need to remove the onClick event from the inline code - there's no need to have it there when you're assigning it via jQuery.
<button id="uniqueId">Submit</button>

Universal code that disables buttons onclick

I have a next issue:
My application contains many buttons that make async requests to the server, currently if user is fast enough to click button more than one time - same request gets executed twice or more and data on the server gets duplicated.
Is there a way to disable clicked button, until the request is executed?
Someone suggested this solution:
$("input[type='button']")
.each(function () {
var el = $(this);
var onclickFunction = el.attr('onclick'), alreadyChecked = el.attr('clickHandler');
if (typeof onclickFunction != 'undefined' && typeof alreadyChecked == 'undefined')
{
el.removeAttr("onclick");
el.removeAttr("onclickFunction", onclickFunction);
el.attr('clickHandler', 'true');
el.on('click', function()
{
el.attr("disabled", "disabled");
$.when(eval(onclickFunction)).then(function () { el.removeAttr('disabled'); })
})
}
});
But if i understood correctly, this code runs only once. So if my application contains many views, this code should be executed on each view load.
Is there any more apropriate solution?

Two ways.
1) Use a flag(let's call it requestInProgress) in the page scope that is turned on once the request is made. Once the request is completed, turn off the flag.
2) Disable the button once the button is request is getting processing so as to prevent user from hitting it a second time. Enable the button once the request processing is complete.

Try using .one()
function handleClick(e) {
// not necessary, though notifies user button is disabled
$(this).attr("disabled", true);
// do ajax stuff
$.ajax().then(function() {
$(e.target).removeAttr("disabled")
// reattach `click` when ajax completes
.one("click", handleClick)
})
}
$("input[type='button']").one("click", handleClick)

What I would recommend is using a CSS class to prevent the user from multiple submissions. This also provides you the flexibility of easily styling the appearance for disabled buttons as well, say for their color or opacity in your stylesheet.
Something like this:
function onClickHandler() {
var myButton = $(this);
// check to see if it's already disabled
if (myButton.hasClass('disabled')) {
// if so, just exit out
return;
}
// add the disabled class
myButton.addClass('disabled');
// continue with your processing...
}
If browser compatibility is not an issue, you could also check out the disabled attribute, but I'm personally a bigger fan of using a class.

Having issues with session timeout

Need your valuable feedback on this. I have implemented idletimeout functionalty so that session will expire in 3 minutes if the user is idle.
In three scenario, I am resetting the timer.
On click or tap
after 2 seconds while processing is in progress
on scroll or scrollstart
The problem is sometimes session is getting timeout before the 3 minutes even if I tap, click or scroll and user is redirected to login page even if the function is gets called on tap click or scroll and resettimers is getting called. I am facing a bit hard time to figure out the loophole.
I am posting the code; please let me know if you notice anything.
// Set timeout variables.
var timoutNow = 180000 ;
var ua = navigator.userAgent;
var event = ((ua.match(/iPad/i)) || (ua.match(/iPhone/i)) || (ua.match(/iPod/i))) ? 'touchstart' : 'click';
var logoutUrl = Mobile+'/login.html'; // URL to logout page.
var timeoutTimer;
// Start timers.
function StartTimers() {
timeoutTimer = setTimeout("IdleTimeout()", timoutNow);
//console.log(timoutNow);
}
// Reset timers.
function ResetTimers() {
clearTimeout(timeoutTimer);
StartTimers();
}
// Processing time check.
function Laodtimercheck()
{
setInterval(function(){
if($("body").hasClass("loading-processing")==true)
{
ResetTimers();
}
}, 2000);
}
// Logout the user.
function IdleTimeout() {
sessionStorage.clear();
document.location.href = Mobile+'/login.html';
}
$(document).live(event, function(){
//console.log("Reset timers: ON TAP OR CLICK");
ResetTimers();
});
$(document).mouseover(function() {
//console.log("Reset timers: ONMOUSEOVER");
ResetTimers();
});
$(window).scroll(function() {
//console.log("Reset timers: SCROLL");
ResetTimers();
});
$(document).live("scrollstart", function(){
//console.log("Reset timers: SCROLLSTART");
ResetTimers();
});
EDIT: setTimeout only working first two times; next time ResetTimers are getting invoked but the setTimeout is not working or I might be missing something here as the session is getting timed out as per pervious two call time only....

The real problem that you're having is the folowing: "ResetTimers" not being invoke enough.
Why is not being invoked enough? I'll try to answer that.
All the logic is Ok with a few exceptions. There are two "problematic" events that not work or I think don't work like you want.
1.- LIVE (event)
That event is not being fired never. You cannot attach a live event to a document, yo need to specify a node, like html or body.
$("body").live(event, function(){
//console.log("Reset timers: ON TAP OR CLICK");
ResetTimers();
});
That's why when clicked the timer don't reset.
Another (and recomended) way to use a variable for binding events is to use .delegate().
Since jQuery 1.4.3+ is the recomended way of doing this.
$(document).delegate("body", event, function(){
//console.log("Reset timers: ON TAP OR CLICK (delegate)");
ResetTimers();
});
Any of those (live on body or delegate) would work and timer get reset on click or tap event.
2.- MOUSEOVER
There isn't a problem per se with this event, but I think it would be insuficient. MouseOver only fires where the pointer get on screen first time, if the mouse don't leave the window the mouseover never fires again. Maybe, a better or added way of control "mouse hovering" on the document is to use onmousemove event. Like I said in a comment before, I don't know if you want to be strict on this, so I left you a proposal and let's see if it fits your needs.
$(document).mouseover(function() {
console.log("Reset timers: ONMOUSEOVER");
ResetTimers();
});
In my tests, events get fires a lot, and the timers get reset on each event without problems. I hope it helps you.

jQuery preventDefault() doesn't work like I expect - is this a jQuery Bug?

This is simplified code to exactly reproduce a problem I'm having with jQuery.
I would expect it to cancel the original click, then trigger the click event again which in turn would cause the browser to load the href of the url.
<script type="text/javascript">
$( function()
{
var confirmed = false;
$('a').click( function( event )
{
if ( confirmed == false )
{
event.preventDefault();
confirmed = true;
$(event.target).trigger( 'click' );
}
});
});
</script>
Original Question Here
I do not want to change window.location. I want to trigger so that any event handlers that have been bound to the click event will fire too. It just so happens that I also want the browser to follow the link.

.trigger('click') won’t trigger the browser’s default action — it will just trigger jQuery event handlers bound to that event on that element.
Take a look at this answer — you need to create and fire a click event yourself. Here’s the code from that answer:
function fireEvent(obj,evt){
var fireOnThis = obj;
if( document.createEvent ) {
var evObj = document.createEvent('MouseEvents');
evObj.initEvent( evt, true, false );
fireOnThis.dispatchEvent( evObj );
} else if( document.createEventObject ) {
var evObj = document.createEventObject();
fireOnThis.fireEvent( 'on' + evt, evObj );
}
}

Your event handler will always be run when you trigger a "click" event, and before the default behavior happens. So no, it's not a bug.
edit — If you want the default action to happen when the element is clicked and your various conditions are satisfied, just return from your handler.
$('a').click( function( event )
{
if ( confirmed == false )
{
event.preventDefault();
confirmed = true;
}
else
return;
});
When your handler returns, the browser will carry on with the default behavior.
edit again — and of course if you want to simply carry out programmatically the default action of an <a> tag with an "href" attribute, it's just:
window.location = $(element).attr('href');
No need for a "click" event at all.

preventDefault() doesn't cancel the jquery bound click action; it cancels the 'default' click action that is inherent to an anchor tag. unbind() is the proper function for canceling any action/function that is bound to an object.

It looks like you have one state where you want to inhibit the default action (and update a flag), and another state where you simply want the default action to apply. Wouldn't removing the else case entirely do the trick? With no preventDefault() the default click action will still run.
Edit: Pointy's answer now shows your code updated similarly.
Edit: I'm still not entirely sure what you're going for, but if for some reason you must trigger manually, one way to prevent a stack overflow due to recursion would be to assign a custom event (i.e., not click), and then always suppress the default action. Then in your conditional, either do or don't fire the custom event.
So, something like this (untested):
$('a')
.bind('fancyclick', function () { // Your special click logic
changeStatusOf( confirmed );
doCrazyStuff();
location.replace( $(this).attr('href') ); // or whatever
})
.click( function (e) {
e.preventDefault(); // Always suppress natural click
if ( confirmed ){
$(this).trigger('fancyclick'); // Fire the special click
}
});

I'll simply write while I analyse, hoping it'll be easy to follow and easy to compare to your code. Kick me when I can optimize/enhance my replies in any way.
checking - part 1
Move the "preventDefault" outside of the "if" statement! If you don't move it outside of the "if", the code will skip the "preventDefault" if confirmed == true.
<script type="text/javascript">
$( function()
{
var confirmed = false;
$('a').click( function( event )
{
event.preventDefault();
if ( confirmed == false )
{
confirmed = true;
$(event.target).trigger( 'click' );
}
});
});
</script>
checking - part 2
Besides that, I'm wondering about the existence of "var confirmed" in general. The code would also work flawless without it since you're not using the confirmed variable in the function anywhere else...
<script type="text/javascript">
$( function()
{
$('a').click( function( event )
{
event.preventDefault();
$(event.target).trigger( 'click' );
});
});
</script>
checking - part 3
Knowing you can replace the trigger with a simple click, did you try that?
<script type="text/javascript">
$( function()
{
$('a').click( function( event )
{
event.preventDefault();
$(event.target).click();
});
});
</script>
checking - part 4
If the click still fails on the target element, it's definitely time to inspect (using "FireBug on Firefox" or alike) if "event.target" holds an object at all. You never know...
checking - part 5
One more thing: I don't see any Document Ready checking, so I hope you've put that script at the end of your file, right before the "</body>" tag. If you load it in the "<head>" without checking Document Ready, it might happen that javascript tries to bind the event to an element that is yet to be loaded into the dom... which would be like throwing feathers against a 9 Inch steel plate... nothing will happen. ;)
that's all
That's all that comes to mind as an answer to your question. One of them could fix the issue you're having. At least, that's what I hope. These little snippets here at stackoverflow leave massive probabilities related to what we don't see. It's hard to be sure what might be missing when you don't have the "complete view". ;)

How about doing something like creating a link offscreen that would handle the final click? That way, you can prevent the click of the original link, handle the code, then proceed to trigger the click of the hidden copy.

window.beforeunload called twice in Firefox - how to get around this?

I'm creating a popup window that has a beforeunload handler installed. When the "Close" file menu item is used to close the popup, the beforeunload handler is called twice, resulting in two "Are you sure you want to close this window?" messages appearing.
This is a bug with Firefox, and I've reported it here, but I still would like a way to prevent this from happening. Can you think of a sane way of detecting double beforeunload to prevent the double message problem? The problem is that Firefox doesn't tell me which button in the dialog the user elected to click - OK or cancel.

<script type="text/javascript">
var onBeforeUnloadFired = false;
window.onbeforeunload = function ()
{
if (!onBeforeUnloadFired) {
onBeforeUnloadFired = true;
event.returnValue = "You have attempted to leave this page. If you have made any changes to the fields without clicking the Save button, your changes will be lost. Are you sure you want to exit this page?";
}
window.setTimeout("ResetOnBeforeUnloadFired()", 10);
}
function ResetOnBeforeUnloadFired() {
onBeforeUnloadFired = false;
}
</script>

Set a variable in the handler to prevent the dialog coming up the second time. Use setTimeout to reset it afterwards.

This is definitely a FF bug. I've reported it at https://bugzilla.mozilla.org/show_bug.cgi?id=531199

The best solution I've found is to use a flag global variable that is reset after so many milliseconds, say 500 (this ensures that the function can be called again, but not immediately after its appearance).
See last code in:
http://social.msdn.microsoft.com/Forums/en/sharepointinfopath/thread/13000cd8-5c50-4260-a0d2-bc404764966d

I've found this problem in Chrome 21, Firefox 14, IE 7-9, Safari 5 (on PC).
The following works on all of these browsers. If one removes the window.onbeforeunload function during the event this will prevent the second call. The trick is to reset the window.onbeforeunload function if the user decides to stay on the page.
var window_on_before_unload = function(e) {
var msg;
// Do here what you ever you need to do
msg = "Message for user";
// Prevent next "window.onbeforeunload" from re-running this code.
// Ensure that if the user decides to stay on the page that
// this code is run the next time the user tries to leave the page.
window.onbeforeunload = set_on_before_unload;
// Prepare message for user
if (msg) {
if (/irefox\/([4-9]|1\d+)/.test(navigator.userAgent))
alert(msg
+ '\n\nThe next dialog will allow you to stay here or continue\nSee Firefox bug #588292');
(e = e || window.event).returnValue = msg;
return msg;
}
};
// Set window.onbeforeunload to the above handler.
// #uses window_on_before_unload
// #param {Event} e
var set_on_before_unload = function(e) {
// Initialize the handler for window.onbeforeunload.
window.onbeforeunload = window_on_before_unload;
}
// Initialize the handler for window.onbeforeunload.
set_on_before_unload();

Create a global variable that is set to true inside the handler. Only show the alert/popup when this variable is false.

I use the following snippet to track the exitcount
When the page loads the following variable exitCount is initialized
if (typeof(MTG) == 'undefined') MTG = {};
MTG.exitCount=0;
and in the Window unload event
$(window).bind("beforeunload", function(){
if (MTG.exitCount<=0)
{
//do your thing, save etc
}
MTG.exitCount++;
});

I've found that instead of doing your own call to confirm(), just do even.preventDefault(); within the beforeunload event. Firefox throws up its own confirm dialog.
I'm not sure if this is the correct/standard thing to do, but that's how they're doing it.

I have a document opening another popup window with window.open. In the original window I have registered (with jquery) a listener for "unload" event like this:
var popup_window = window.open(...)
$(popup_window).on('unload', function(event) ...
I have came across this page because the event was effectively triggering twice. What I have found is that it is not a bug, it triggers twice because it fires once for "about:blank" page being replaced by your page and another for your page being unloaded.
All I have to do is to filter the event that I am interested in by querying the original event:
function (event) {
var original_url = e.originalEvent.originalTarget.URL;
if (original_url != 'about:blank')
{
... do cool things ...
}
}
I don't know if this applies to the original question, because it is a special case of a window opening another, but I hope it helps.