JQuery / dirty forms / window.onbeforeunload only triggered after link selection - javascript

I'm trying to implement a warning for the users in case they are leaving the form without saving.
The warning dialog works as expected but with the only exception that when the user chooses to 'Stay on Page', the selected side menu entry changed to the one the user clicked on (form is the same).
How can I make sure that the same menu item is still selected once the user chooses to 'Stay on Page'?
var warnMessage = "Unsaved changes. Do you really want to leave the page?";
$(document).ready(function () {
$('a.k-link').on('click', function () {
window.onbeforeunload = function () {
if (isDirty) return warnMessage;
}
});
});

You might find it easier (and possibly more consistent across browsers) to use a confirm prompt (remember, it's a blocking dialog).
<script>
var warnMessage = "Unsaved changes. Do you really want to leave the page?";
$('a.k-link').on('click', function (e) {
if (isDirty && !confirm(warnMessage)) {
e.preventDefault();
}
});
</script>
There are at least two reasons to avoid onbeforeunload:
The spec doesn't require a browser to display the message you
provide, and not all browsers do, and
the correct event is actually beforeunload
You can and should handle this event through window.addEventListener() and the beforeunload event. More documentation is available there. (MDN)
I'm just guessing, since the Kendo UI scripts aren't exactly fun to read through, but the 'selected' class is getting applied because a navigation event was started, even though you cancel it; the Kendo script is probably just listening for a successful click. onbeforeunload and beforeunload both happen after the click event has resolved (AFAIK, anyway).

Following worked for me (adding e.stopPropagation):
$('a.k-link').on('click', function (e) {
if (isDirty && !confirm(warnMessage)) {
e.preventDefault();
e.stopPropagation();
} });
or by returning false:
$('a.k-link').on('click', function (e) {
if (isDirty && !confirm(warnMessage)) {
return false;
} });

Related

Preventing users from accidentally navigating away from unsaved pages

I got the snippet below from this SO post, and it works when a user tries to reload the page or close the browser etc. but if the user clicks on a link then it lets them naivagate away, and then incorrectly starts displaying the message on the wrong page. I am using pjax for the links.
$(document).ready(function () {
$('textarea').change(function () {
window.onbeforeunload = function () { return "Your changes to the survey have not been saved?" };
});
});
You should use onbeforeunload like this, inconditionally:
<script type="text/javascript">
saved=true; // initially, it is saved (no action has been done)
window.onbeforeunload = confirmExit;
function confirmExit() {
if (!saved) {
return "You did not save, do you want to do it now?";
}
}
</script>
It is not safe to handle this event only when another event is fired. The onchange event of your textarea here probably don't fire before you click on a link so the window won't handle the onbeforeunload at all. The link will work as expected: you will get redirected.
To deal with the saved flag, you could listen to what happens in your textarea, for example, when the user is actually typing something:
$('textarea').keyup(function(){
saved=false;
});
Then, if you save the data in ajax, the save button could set it back to true:
$('#btnSave').click(function(){
// ajax save
saved=true;
});
Otherwise, it will load the next page with the saved flag on.
what about something like the following?
Listening on all <a> links and then, depending on whether the variable needToSave is set to true, showing the message or letting it go.
var needToSave = false; // Set this to true on some change
// listen on all <a ...> clicks
$(document).click("a", function(event){
if (needToSave == true) {
alert("You need to save first");
event.preventDefault();
return;
}
});
UPDATE (as per Roasted's suggestion) this should trigger the unload event every time the link is clicked and perform your existing logic:
// listen on all <a ...> clicks
$(document).click("a", function(event){
$(window).trigger("unload");
});
jsFiddle here - http://jsfiddle.net/k2fYM/

Alert for unsaved changes in form

I want to write Jquery code in master file, so that if there if user changes page and there is any unsaved changes user should get alert.
I got one answer from this: link
However in most solution I will have to write code on all pages. I want it to write only at one place so that everybody dont have to worry to write it in their modules. My code is like:
<script type="text/javascript">
var isChange;
$(document).ready(function () {
$("input[type='text']").change(function () {
isChange = true;
})
});
$(window).unload(function () {
if (isChange) {
alert('Handler for .unload() called.');
}
});
</script>
But everytime i make changes in text boxes .change() event is not firing.
What can be wrong in the code?
EDIT:
I changed .change() to .click and it is fired. i am using jquery 1.4.1..is it because of jquery version that change() is not working?
This is what i am using, Put all this code in a separate JS file and load it in your header file so you will not need to copy this again and again:
var unsaved = false;
$(":input").change(function(){ //triggers change in all input fields including text type
unsaved = true;
});
function unloadPage(){
if(unsaved){
return "You have unsaved changes on this page. Do you want to leave this page and discard your changes or stay on this page?";
}
}
window.onbeforeunload = unloadPage;
EDIT for $ not found:
This error can only be caused by one of three things:
Your JavaScript file is not being properly loaded into your page
You have a botched version of jQuery. This could happen because someone edited the core file, or a plugin may have overwritten the $
variable.
You have JavaScript running before the page is fully loaded, and as such, before jQuery is fully loaded.
Make sure all JS code is being placed in this:
$(document).ready(function () {
//place above code here
});
Edit for a Save/Send/Submit Button Exception
$('#save').click(function() {
unsaved = false;
});
Edit to work with dynamic inputs
// Another way to bind the event
$(window).bind('beforeunload', function() {
if(unsaved){
return "You have unsaved changes on this page. Do you want to leave this page and discard your changes or stay on this page?";
}
});
// Monitor dynamic inputs
$(document).on('change', ':input', function(){ //triggers change in all input fields including text type
unsaved = true;
});
Add the above code in your alert_unsaved_changes.js file.
A version that use serialization of the form :
Execute this code, when dom ready :
// Store form state at page load
var initial_form_state = $('#myform').serialize();
// Store form state after form submit
$('#myform').submit(function(){
initial_form_state = $('#myform').serialize();
});
// Check form changes before leaving the page and warn user if needed
$(window).bind('beforeunload', function(e) {
var form_state = $('#myform').serialize();
if(initial_form_state != form_state){
var message = "You have unsaved changes on this page. Do you want to leave this page and discard your changes or stay on this page?";
e.returnValue = message; // Cross-browser compatibility (src: MDN)
return message;
}
});
If the user change a field then manually rollback, no warn is displayed
change event is fired once the user blurs from input not on every single character inputed.
If you need it to be called every time something is changed (even if focus is still in that input field) you would have to rely on combination of keyup and bunch of events to keep track of pasting/cuting using mouse only.
P.S.
I hope you're aware that your approach to detecting changes isn't the best one? If user input some text, leaves the field and then reverts the changes the script would still alert him about modified text.
you should register events for not only inputs but also textareas, if you mean textarea with text box. You can use keyup for isChange, so that you don't wait for user to blur from this area.
$("input[type='text'], textarea").keyup(function () {
isChange = true;
})
This is really just a different version of #AlphaMale's answer but improved in a few ways:
# Message displayed to user. Depending on browser and if it is a turbolink,
# regular link or user-driven navigation this may or may not display.
msg = "This page is asking you to confirm that you want to leave - data you have entered may not be saved."
# Default state
unsaved = false
# Mark the page as having unsaved content
$(document).on 'change', 'form[method=post]:not([data-remote]) :input', -> unsaved = true
# A new page was loaded via Turbolinks, reset state
$(document).on 'page:change', -> setTimeout (-> unsaved = false), 10
# The user submitted the form (to save) so no need to ask them.
$(document).on 'submit', 'form[method=post]', ->
unsaved = false
return
# Confirm with user if they try to go elsewhere
$(window).bind 'beforeunload', -> return msg if unsaved
# If page about to change via Turbolinks also confirm with user
$(document).on 'page:before-change', (event) ->
event.preventDefault() if unsaved && !confirm msg
This is better in the following ways:
It is coffeescript which IMHO automatically makes it better. :)
It is entirely based on event bubbling so dynamic content is automatically handled (#AlphaMale's update also has this).
It only operates on POST forms as GET forms do not have data we typically want to avoid loosing (i.e. GET forms tend to be search boxes and filtering criteria).
It doesn't need to be bound to a specific button for carrying out the save. Anytime the form is submitted we assume that submission is saving.
It is Turbolinks compatible. If you don't need that just drop the two page: event bindings.
It is designed so that you can just include it with the rest of your JS and your entire site will be protected.
Why not simply bind the event to the change callback?
$(":input").change(function()
{
$(window).unbind('unload').bind('unload',function()
{
alert('unsaved changes on the page');
});
});
As an added bonus, you can use confirm and select the last element that triggered the change event:
$(":input").change(function()
{
$(window).unbind('unload').bind('unload',(function(elem)
{//elem holds reference to changed element
return function(e)
{//get the event object:
e = e || window.event;
if (confirm('unsaved changes on the page\nDo you wish to save them first?'))
{
elem.focus();//select element
return false;//in jQuery this stops the event from completeing
}
}
}($(this)));//passed elem here, I passed it as a jQ object, so elem.focus() works
//pass it as <this>, then you'll have to do $(elem).focus(); or write pure JS
});
If you have some save button, make sure that that unbinds the unload event, though:
$('#save').click(function()
{
$(window).unbind('unload');
//rest of your code here
});
Without jQuery:
var unsaved = false;
document.addEventListener("DOMContentLoaded", function() {
var els = document.querySelectorAll('textarea, input, select');
els.forEach( function(el) {
el.addEventListener('change', function() {
unsaved = true;
});
});
window.addEventListener('beforeunload', function(event) {
if(unsaved){
event.returnValue = "string";
}
});
var forms = document.querySelectorAll('form');
forms.forEach( function(form) {
form.addEventListener('submit', function() {
unsaved = false;
});
});
});
The weird 'string' hack explanation can be found here.
I use $('form').change etc. function to set a dirty bit variable. Not suitable to catch all changes (as per previous answers), but catches all that I'm interested in, in my app.

Notify user page was modified if trying to exit, what's the technique?

If a user is on a page with a form, and they have edited something, and then try and navigate to another page, how can I notify them?
How do people do this?
Is it a matter of computing a hash of all the input fields and comparing if they are exiting the page?
Is there a on page unload event?
I like to only prompt the user if they've actually changed something. Something like this:
var changesMade = false;
function onDataChanged() {
changesMade = true;
}
$('input:text, textarea, select').change(onDataChanged);
$('input:checkbox, input:radio').click(onDataChanged);
$(window).bind('beforeunload', function() {
if (changesMade) {
return 'Changes have been made. Are you sure you want to leave the page?';
} else {
return null;
}
});
The onbeforeunload event:
$(window).bind('beforeunload', function() {
return 'Are you sure?';
});
On some browsers this displays the message, on other browsers the message is not shown. It does show a dialog with a Leave and a Stay button on all browsers though (as far as I know) so that the user can choose.
Use beforeunload event of window.
$(window).bind('beforeunload', function() {
return confirm("Alert user");
});

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!

Way to know if user clicked Cancel on a Javascript onbeforeunload Dialog?

I am popping up a dialog box when someone tries to navigate away from a particular page without having saved their work. I use Javascript's onbeforeunload event, works great.
Now I want to run some Javascript code when the user clicks "Cancel" on the dialog that comes up (saying they don't want to navigate away from the page).
Is this possible? I'm using jQuery as well, so is there maybe an event like beforeunloadcancel I can bind to?
UPDATE: The idea is to actually save and direct users to a different webpage if they chose cancel
You can do it like this:
$(function() {
$(window).bind('beforeunload', function() {
setTimeout(function() {
setTimeout(function() {
$(document.body).css('background-color', 'red');
}, 1000);
},1);
return 'are you sure';
});
});
The code within the first setTimeout method has a delay of 1ms. This is just to add the function into the UI queue. Since setTimeout runs asynchronously the Javascript interpreter will continue by directly calling the return statement, which in turn triggers the browsers modal dialog. This will block the UI queue and the code from the first setTimeout is not executed, until the modal is closed. If the user pressed cancel, it will trigger another setTimeout which fires in about one second. If the user confirmed with ok, the user will redirect and the second setTimeout is never fired.
example: http://www.jsfiddle.net/NdyGJ/2/
I know this question is old now, but in case anyone is still having issues with this, I have found a solution that seems to work for me,
Basically the unload event is fired after the beforeunload event. We can use this to cancel a timeout created in the beforeunload event, modifying jAndy's answer:
$(function() {
var beforeUnloadTimeout = 0 ;
$(window).bind('beforeunload', function() {
console.log('beforeunload');
beforeUnloadTimeout = setTimeout(function() {
console.log('settimeout function');
$(document.body).css('background-color', 'red');
},500);
return 'are you sure';
});
$(window).bind('unload', function() {
console.log('unload');
if(typeof beforeUnloadTimeout !=='undefined' && beforeUnloadTimeout != 0)
clearTimeout(beforeUnloadTimeout);
});
});
EDIT: jsfiddle here
Not possible. Maybe someone will prove me wrong... What code do you want to run? Do you want to auto-save when they click cancel? That sounds counter-intuitive. If you don't already auto-save, I think it makes little sense to auto-save when they hit "Cancel". Maybe you could highlight the save button in your onbeforeunload handler so the user sees what they need to do before navigating away.
I didn't think it was possible, but just tried this idea and it works (although it is some what of a hack and may not work the same in all browsers):
window.onbeforeunload = function () {
$('body').mousemove(checkunload);
return "Sure thing";
};
function checkunload() {
$('body').unbind("mousemove");
//ADD CODE TO RUN IF CANCEL WAS CLICKED
}
Another variation
The first setTimeout waits for the user to respond to the browser's Leave/Cancel popup. The second setTimeout waits 1 second, and then CancelSelected is only called if the user cancels. Otherwise the page is unloaded and the setTimeout is lost.
window.onbeforeunload = function(e) {
e.returnValue = "message to user";
setTimeout(function () { setTimeout(CancelSelected, 1000); }, 100);
}
function CancelSelected() {
alert("User selected stay/cancel");
}
window.onbeforeunload = function() {
if (confirm('Do you want to navigate away from this page?')) {
alert('Saving work...(OK clicked)')
} else {
alert('Saving work...(canceled clicked)')
return false
}
}
with this code also if user clicks on 'Cancel' in IE8 the default navigation dialog will appear.

Categories

Resources