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Trigger event when user clicks the browsers back button

Is it possible with jquery to trigger a function when the user clicks the browsers back button.
I have a lightbox/widget that when open fills the window when it is open. There is a close button etc but this would be good if this closed if a user hit the back button by mistake.
I have this so far but the function doesnt seem to run at all
$(window).on("navigate", function (event, data) {
event.preventDefault();
console.log('BACK PRESSED');
var direction = data.state.direction;
if (direction === 'back') {
if(widgets.full_active){
$('.close', widgets.active_widget).click();
event.preventDefault();
console.log('CLOSE THIS');
}
}
if (direction === 'forward') {
// do something else
}
});
By not running this line at the start of the function event.preventDefault(); should mean the page never changes

Usually, I do this using the native JavaScript API from the browser, like described here: Manipulating the Broser History.
With jQuery, I see people usually using this plugin: History.js, although I have no idea what is it's status.
The event you're looking for is onpopstate.
A popstate event is dispatched to the window every time the active
history entry changes between two history entries for the same
document.

Clicking a button added by JavaScript clicks through it as well

I'm working on a script that adds a button that floats on top of a Facebook user's profile photo thumbnail.
Here's a screenshot:
This button, when clicked, returns the Facebook ID of the profile that is being viewed in a prompt. That part works fine (but you'd need to be logged in and looking at a profile besides yours, otherwise there'd be a missing element).
Screenshot:
What's bothering me though, is after clicking the button, and pressing Cancel or Okay in the prompt, the click actually goes through the button and clicks the profile picture thumbnail itself. A single click is clicking both items!
Is there any way we can make it so that the area below the button itself is not clickable? But the rest of the profile picture is?
I've tried searching on this topic but couldn't find much results. Even if I try to search for something like "Add padding below/under button JavaScript", I'm getting padding around the button, and not directly below it
in a z-axis point of view.
Here's the script code, you can copy paste it in the console directly. That is, if you have a Facebook account and are logged in. Also this only works on profiles besides yours (otherwise data-profileid would be missing).
// Create the button
var btn = document.createElement("BUTTON");
var t = document.createTextNode("FBID"); // To replace with icon
btn.appendChild(t);
// Add a listener
btn.addEventListener("click", getFBID);
// Styling (positioning)
btn.style.display="block";
btn.style.position="absolute";
btn.style.top="4px";
btn.style.right="4px";
// Function to get Facebook ID
function getFBID() {
prompt("Copy it:", document.querySelectorAll("[data-profileid]")[0].getAttribute("data-profileid"));
}
// Append button to profile picture
document.getElementsByClassName("profilePicThumb")[0].appendChild(btn);
Oh yeah, I feel the reason why this is happening is because I am appending to an anchor link. Just in case this info would be useful.
Any help appreciated, thank you!

Try to prevent the default actions for the click like this:
btn.addEventListener("click", function(event){
event.preventDefault();
event.stopPropagation();
getFBID();
return false;
});
EDIT: use event.stopPropagation();
(compare to this thread How to stop event bubbling on checkbox click)

Try this
// Create the button
var btn = document.createElement("BUTTON");
var t = document.createTextNode("FBID"); // To replace with icon
btn.appendChild(t);
// Add a listener
btn.addEventListener("click", getFBID);
// Styling (positioning)
btn.style.display="block";
btn.style.position="absolute";
btn.style.top="4px";
btn.style.right="4px";
// Function to get Facebook ID
function getFBID() {
prompt("Copy it:", document.querySelectorAll("[data-profileid]")[0].getAttribute("data-profileid"));
return false; // Try returning false here..
}
// Append button to profile picture
document.getElementsByClassName("profilePicThumb")[0].appendChild(btn);
getFBID in this case is a callback for the event that is raised on the click of the button. returning false will make sure that the event is not propagated to its parent and hence will not raise the parent's event or call the eventhandler.

How can I put a button in the down state?

Suppose I have a button, which goes into a down state when someone clicks on it, but before the mouse is released.
Now suppose instead that someone presses the 'a' key, I want the button to go into the down state, until the key is released, at which point it is triggered. Is this possible?

After dooing some research here is the final answer I got:
You can trigger mousedown or mouseup events on a button element using keyup and keydown
if your button is programmed to change its style according to these events than you are good to go.
See this fiddle example: http://jsfiddle.net/FwKEQ/15/
Note that if you use jQuery's UI components than it does work. But for standard buttons there is no way that you can move them to their pressed state using javascript
html:
<button id="jQbutton">Press 'A' to move me to pressed state</button>
Javascript:
<script>
$( "#jQbutton" ).button();
$(document).keydown(function(event) {
if ((event.keyCode === 97)||(event.keyCode === 65))
$("#jQbutton").mousedown();
});
$(document).keyup(function(event) {
if ((event.keyCode === 97)||(event.keyCode === 65))
$("#jQbutton").mouseup();
});
</script>
EDIT:
There might be a hack that we could utilize:
using accesskey for the button element and then try to simulate the accesskey press (that i am not sure if possible)
here is where i'm at so far http://jsfiddle.net/FwKEQ/28/
EDIT 2:
So looking further into this topic i have found the following:
Default buttons (without styles) are rendered by the OS, I was not able to find a formal proof for that but if you try to load the same page using a mac OS you'll get mac OS style buttons while in windows you will get the "ugly" gray button.
Because the default buttons are rendered by the OS they comply to OS events meaning events that are sent by the browser and are trusted.
this is not true for custom styled buttons as they comply to CSS an JS to change their appearance on press that is why the JQ button is affected by JS.
so to summarize you would need a trusted press event to fire on a default button to change its style and that cannot be done due to security constraints.
read a bit more about trusted events here: http://www.w3.org/TR/DOM-Level-3-Events/#trusted-events
and if someone could find a formal reference with regards to the default buttons being rendered by the OS please comment or edit this answer.

Unfortunately the rendering of the active state on default buttons neither
is a simple matter of css styling nor can be easily changed by applying
javascript.
An option to do this on default buttons is to use the hotkeys jquery plugin: https://github.com/jeresig/jquery.hotkeys or implement alternative key codes for different browsers.
and to apply 50% opacity to the default button when pressed (to indicate the keydown).
(To me it seems almost perfect ;-) It probably is as good as it can easily get to work across platforms and browsers using default buttons.
jsfiddle DEMO
and the code ...
html:
<button id="test">Test Button</button>
Selected: <span class="selected" id="out"></span>
javascript:
$('#test').click(function () {
fn_up();
});
fn_down = function(event){
$('#test').css("opacity", 0.5);
$('#test').focus();
event.preventDefault();
}
fn_up = function(event){
$('#test').css("opacity", 1);
$('#out').append(" test");
event.preventDefault();
}
//to bind the event to the 'a' key
$(document).bind('keydown','a', fn_down);
$(document).bind('keyup','a', fn_up);
//to get the same effect with the 'space' key
$(document).bind('keydown','space', fn);
$(document).bind('keyup','space', fn2);
In the fiddle I apply it to the space button and the mousedown/up to achieve the same effect with all events (but you could just use it with the 'a' key ... this is a matter of taste).

Here is a jsfiddel that shows how it's done using jQuery: http://jsfiddle.net/KHhvm/2/
The important part:
$("#textInput").keydown(function(event) {
var charCodeFor_a = 65;
if ( event.which == charCodeFor_a ) {
// "click" on the button
$('#button').mousedown();
// make the button look "clicked"
$('#button').addClass('fakeButtonDown');
// do some stuff here...
// release the button later using $('#button').mousedown();
}
});
The button event is triggered when entering "a" in the input field. But as Mark pointed out you need to fake the styling for the clicked button because the browser doesn't do it.
Edit: I'm not sure if you're using jQuery in your project. I just wanted to show that it is possible at all. If it can be done with the jQuery library there is also a way to do it in pure javascript. ;)

Javascript Window.onbeforeunload trapping control that fired event

I have an C#.NET MVC3 web app and I have a question related to the attached Stackoverflow question. I am using a window.beforeunload event to see if there have been changes made on my View. If so, I alert the user that they have unsaved changes. However, if they selected the Create (submit) button, the dialog alerting the user still pops up. I want to NOT pop up the dialog if the Create button is selected. Any ideas? Is there a way to see which control was clicked?

I can think of 2 solutions:
$('#submitBtn').click(function() {
unbindOnBeforeUnload();
});
// OR
// maybe you have multiple cases where you don't want this triggered,
// so this will be better
var shouldTriggerOnBeforeUnload = true;
$('#submitBtn').click(function() {
shouldTriggerOnBeforeUnload = false;
});
...
$(document).unload(function() {
if (shouldTriggerOnBeforeUnload) {
confirm();
}
});
I've written it in a jQuery-like syntax, but only to keep the code concise, you can adapt it to anything you want.

Capturing result of window.onbeforeunload confirmation dialog

Is there a way to capture to result of the window.onbeforeunload confirmation dialog like the one below from Stack Overflow (this happens when leaving the 'Ask Question' page without posting the question)?
This is how it appears in Chrome, I believe it's slightly different in other browsers, but you always have some form of yes/no buttons.
Presumably if they're still on the offending page after the event has been triggered they chose to stay and you could probably figure this out by watching the sequence of js. However I would like to know how to determine if they clicked "Leave this page"?
I've implemented this like below:
// concept taken from SO implementation
function setConfirmUnload(showMessage, message) {
window.onbeforeunload = showMessage ? (message ? message : "this is a default message") : null;
}
// pseudo code
listen to changes on inputs
if any inputs fire a change event
call setConfirmUnload(true, 'My warning message')
note I'm using jQuery within my site.
I'm essentially trying to implement a Gmail like drafting implementation, wherein if a user leaves a page with a form they've made changes to without saving they're warmed with a similar dialog. If they choose to discard they're changes and leave the page, I need to clean up some temporary records from the database (I'm thinking an AJAX call, or simply submitting the form with a delete flag) then sending them on their way.
My question also relates to:
jQuery AJAX call in onunload handler firing AFTER getting the page on a manual refresh. How do I guarantee onunload happens first?

You can have the exit confirmation using window.onbeforeunload but there isn't a way to find out which button the user clicked on.
To quote an earlier response from jvenema from this thread:
The primary purpose for the
beforeunload is for things like
allowing the users the option to save
changes before their changes are lost.
Besides, if your users are leaving,
it's already too late [...]

How about this:
$( window ).bind( 'beforeunload' , function( event ) {
setTimeout( function() {
alert( 'Hi againe!' );
} );
return '';
} ).bind( 'unload', function( event ) {
alert( 'Goodby!' );
} );

Late to the party, but I found the following code (in TypeScript) to be a decent way to detect if the person clicked on 'Ok' on that confirmation dialogue window.
public listenToUnloadEvents(): void {
window.addEventListener('beforeunload', (e) => {
const confirmationMessage = '\o/';
(e || window.event).returnValue = confirmationMessage; // Gecko + IE
return confirmationMessage; // Webkit, Safari, Chrome etc.
});
window.addEventListener('unload', () => {
this.sendNotification(Action.LEFT)
});
}
I'm not sure how much time you have to run code in the unload event, but in this instance, I am sending a notification through Socket.io, so it's very quick at completing.
As for detecting the cancel on that notification, as someone else mentioned, creating a global variable like let didEnterBeforeUnload = false could be set to true when the beforeunload event fires. After this, by creating the third event, like so (again, in TypeScript), you can infer the user pressing cancel
window.addEventListener('focus', (e) => {
if (didEnterBeforeUnload) {
console.log('pressed cancel')
}
didEnterBeforeUnload = false
});
As a side-note though, these events won't (iirc) fire unless you have interacted with the page. So make sure to click or tap into the page before trying to navigate away during your testing.
I hope this helps anyone else out there!