I'm working on a browser extension that needs to be constantly running, even after an automatic refresh in the background. The problem is, that the page randomly automatically unloads and the script just shuts off. I need to find a way to keep the content script on at all times. Here's part of the code:
// content.js:
function run(fn) {
if(typeof(Worker) !== "undefined") {
if(typeof(w) == "undefined") {
w = new Worker(URL.createObjectURL(new Blob(['('+fn+')()'])));
}
w.onmessage = function(event) {
if (isNaN(grabbedmin) && ID) {
bump() // Note: the bump function refreshes in the page.
w.terminate();
}
if ($("[href='/server/bump/" + ID + "']").text().includes("Bump")) {
bump()
w.terminate();
}
document.getElementById("bumpcount").innerHTML = "Autobumper Enabled: " + getCurrentTimestamp();
if (numberwow == grabbedmin) {
bump()
w.terminate();
}
};
}
}
The code above basically gets run every minute by this worker:
// content.js:
const worker = run(function() {
var i = 0;
function timedCount() {
i = i + 1;
postMessage(i);
setTimeout(function(){timedCount()},1000);
}
timedCount();
});
Is there a way for background.js to detect that content.js is not running (or that the page is unloaded) when it should be and then reload it?
Note: You can find the script here: https://github.com/Theblockbuster1/disboard-auto-bump
After looking through the docs and looking at examples, I put this together:
chrome.tabs.query({
url: ["*://disboard.org/*dashboard/servers", "*://disboard.org/*dashboard/servers/"] // finds matching tabs
}, function(tabs) {
tabs.forEach(tab => {
chrome.tabs.update(tab.id,{autoDiscardable:false});
});
});
chrome.tabs.onUpdated.addListener(function(tabId, changeInfo, tab) {
// checks if the browser automatically re-enabled autoDiscarding and disables it
if (changeInfo.autoDiscardable == true) chrome.tabs.update(tabId,{autoDiscardable:false});
});
I want to capture the browser window/tab close event.
I have tried the following with jQuery:
jQuery(window).bind(
"beforeunload",
function() {
return confirm("Do you really want to close?")
}
)
But it works on form submission as well, which is not what I want. I want an event that triggers only when the user closes the window.
The beforeunload event fires whenever the user leaves your page for any reason.
For example, it will be fired if the user submits a form, clicks a link, closes the window (or tab), or goes to a new page using the address bar, search box, or a bookmark.
You could exclude form submissions and hyperlinks (except from other frames) with the following code:
var inFormOrLink;
$('a').on('click', function() { inFormOrLink = true; });
$('form').on('submit', function() { inFormOrLink = true; });
$(window).on("beforeunload", function() {
return inFormOrLink ? "Do you really want to close?" : null;
})
For jQuery versions older than 1.7, try this:
var inFormOrLink;
$('a').live('click', function() { inFormOrLink = true; });
$('form').bind('submit', function() { inFormOrLink = true; });
$(window).bind("beforeunload", function() {
return inFormOrLink ? "Do you really want to close?" : null;
})
The live method doesn't work with the submit event, so if you add a new form, you'll need to bind the handler to it as well.
Note that if a different event handler cancels the submit or navigation, you will lose the confirmation prompt if the window is actually closed later. You could fix that by recording the time in the submit and click events, and checking if the beforeunload happens more than a couple of seconds later.
Maybe just unbind the beforeunload event handler within the form's submit event handler:
jQuery('form').submit(function() {
jQuery(window).unbind("beforeunload");
...
});
For a cross-browser solution (tested in Chrome 21, IE9, FF15), consider using the following code, which is a slightly tweaked version of Slaks' code:
var inFormOrLink;
$('a').live('click', function() { inFormOrLink = true; });
$('form').bind('submit', function() { inFormOrLink = true; });
$(window).bind('beforeunload', function(eventObject) {
var returnValue = undefined;
if (! inFormOrLink) {
returnValue = "Do you really want to close?";
}
eventObject.returnValue = returnValue;
return returnValue;
});
Note that since Firefox 4, the message "Do you really want to close?" is not displayed. FF just displays a generic message. See note in https://developer.mozilla.org/en-US/docs/DOM/window.onbeforeunload
window.onbeforeunload = function () {
return "Do you really want to close?";
};
My answer is aimed at providing simple benchmarks.
HOW TO
See #SLaks answer.
$(window).on("beforeunload", function() {
return inFormOrLink ? "Do you really want to close?" : null;
})
How long does the browser take to finally shut your page down?
Whenever an user closes the page (x button or CTRL + W), the browser executes the given beforeunload code, but not indefinitely. The only exception is the confirmation box (return 'Do you really want to close?) which will wait until for the user's response.
Chrome: 2 seconds.
Firefox: ∞ (or double click, or force on close)
Edge: ∞ (or double click)
Explorer 11: 0 seconds.
Safari: TODO
What we used to test this out:
A Node.js Express server with requests log
The following short HTML file
What it does is to send as many requests as it can before the browser shut downs its page (synchronously).
<html>
<body>
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.1.1/jquery.min.js"></script>
<script>
function request() {
return $.ajax({
type: "GET",
url: "http://localhost:3030/" + Date.now(),
async: true
}).responseText;
}
window.onbeforeunload = () => {
while (true) {
request();
}
return null;
}
</script>
</body>
</html>
Chrome output:
GET /1480451321041 404 0.389 ms - 32
GET /1480451321052 404 0.219 ms - 32
...
GET /hello/1480451322998 404 0.328 ms - 32
1957ms ≈ 2 seconds // we assume it's 2 seconds since requests can take few milliseconds to be sent.
For a solution that worked well with third party controls like Telerik (ex.: RadComboBox) and DevExpress that use the Anchor tags for various reasons, consider using the following code, which is a slightly tweaked version of desm's code with a better selector for self targeting anchor tags:
var inFormOrLink;
$('a[href]:not([target]), a[href][target=_self]').live('click', function() { inFormOrLink = true; });
$('form').bind('submit', function() { inFormOrLink = true; });
$(window).bind('beforeunload', function(eventObject) {
var returnValue = undefined;
if (! inFormOrLink) {
returnValue = "Do you really want to close?";
}
eventObject.returnValue = returnValue;
return returnValue;
});
I used Slaks answer but that wasn't working as is, since the onbeforeunload returnValue is parsed as a string and then displayed in the confirmations box of the browser. So the value true was displayed, like "true".
Just using return worked.
Here is my code
var preventUnloadPrompt;
var messageBeforeUnload = "my message here - Are you sure you want to leave this page?";
//var redirectAfterPrompt = "http://www.google.co.in";
$('a').live('click', function() { preventUnloadPrompt = true; });
$('form').live('submit', function() { preventUnloadPrompt = true; });
$(window).bind("beforeunload", function(e) {
var rval;
if(preventUnloadPrompt) {
return;
} else {
//location.replace(redirectAfterPrompt);
return messageBeforeUnload;
}
return rval;
})
Perhaps you could handle OnSubmit and set a flag that you later check in your OnBeforeUnload handler.
Unfortunately, whether it is a reload, new page redirect, or browser close the event will be triggered. An alternative is catch the id triggering the event and if it is form dont trigger any function and if it is not the id of the form then do what you want to do when the page closes. I am not sure if that is also possible directly and is tedious.
You can do some small things before the customer closes the tab. javascript detect browser close tab/close browser but if your list of actions are big and the tab closes before it is finished you are helpless. You can try it but with my experience donot depend on it.
window.addEventListener("beforeunload", function (e) {
var confirmationMessage = "\o/";
/* Do you small action code here */
(e || window.event).returnValue = confirmationMessage; //Gecko + IE
return confirmationMessage; //Webkit, Safari, Chrome
});
https://developer.mozilla.org/en-US/docs/Web/Reference/Events/beforeunload?redirectlocale=en-US&redirectslug=DOM/Mozilla_event_reference/beforeunload
jQuery(window).bind("beforeunload", function (e) {
var activeElementTagName = e.target.activeElement.tagName;
if (activeElementTagName != "A" && activeElementTagName != "INPUT") {
return "Do you really want to close?";
}
})
If your form submission takes them to another page (as I assume it does, hence the triggering of beforeunload), you could try to change your form submission to an ajax call. This way, they won't leave your page when they submit the form and you can use your beforeunload binding code as you wish.
As of jQuery 1.7, the .live() method is deprecated. Use .on() to attach event handlers. Users of older versions of jQuery should use .delegate() in preference to .live()
$(window).bind("beforeunload", function() {
return true || confirm("Do you really want to close?");
});
on complete or link
$(window).unbind();
Try this also
window.onbeforeunload = function ()
{
if (pasteEditorChange) {
var btn = confirm('Do You Want to Save the Changess?');
if(btn === true ){
SavetoEdit();//your function call
}
else{
windowClose();//your function call
}
} else {
windowClose();//your function call
}
};
My Issue: The 'onbeforeunload' event would only be triggered if there were odd number of submits(clicks). I had a combination of solutions from similar threads in SO to have my solution work. well my code will speak.
<!--The definition of event and initializing the trigger flag--->
$(document).ready(function() {
updatefgallowPrompt(true);
window.onbeforeunload = WarnUser;
}
function WarnUser() {
var allowPrompt = getfgallowPrompt();
if(allowPrompt) {
saveIndexedDataAlert();
return null;
} else {
updatefgallowPrompt(true);
event.stopPropagation
}
}
<!--The method responsible for deciding weather the unload event is triggered from submit or not--->
function saveIndexedDataAlert() {
var allowPrompt = getfgallowPrompt();
var lenIndexedDocs = parseInt($('#sortable3 > li').size()) + parseInt($('#sortable3 > ul').size());
if(allowPrompt && $.trim(lenIndexedDocs) > 0) {
event.returnValue = "Your message";
} else {
event.returnValue = " ";
updatefgallowPrompt(true);
}
}
<!---Function responsible to reset the trigger flag---->
$(document).click(function(event) {
$('a').live('click', function() { updatefgallowPrompt(false); });
});
<!--getter and setter for the flag---->
function updatefgallowPrompt (allowPrompt){ //exit msg dfds
$('body').data('allowPrompt', allowPrompt);
}
function getfgallowPrompt(){
return $('body').data('allowPrompt');
}
Just verify...
function wopen_close(){
var w = window.open($url, '_blank', 'width=600, height=400, scrollbars=no, status=no, resizable=no, screenx=0, screeny=0');
w.onunload = function(){
if (window.closed) {
alert("window closed");
}else{
alert("just refreshed");
}
}
}
var validNavigation = false;
jQuery(document).ready(function () {
wireUpEvents();
});
function endSession() {
// Browser or broswer tab is closed
// Do sth here ...
alert("bye");
}
function wireUpEvents() {
/*
* For a list of events that triggers onbeforeunload on IE
* check http://msdn.microsoft.com/en-us/library/ms536907(VS.85).aspx
*/
window.onbeforeunload = function () {
debugger
if (!validNavigation) {
endSession();
}
}
// Attach the event keypress to exclude the F5 refresh
$(document).bind('keypress', function (e) {
debugger
if (e.keyCode == 116) {
validNavigation = true;
}
});
// Attach the event click for all links in the page
$("a").bind("click", function () {
debugger
validNavigation = true;
});
// Attach the event submit for all forms in the page
$("form").bind("submit", function () {
debugger
validNavigation = true;
});
// Attach the event click for all inputs in the page
$("input[type=submit]").bind("click", function () {
debugger
validNavigation = true;
});
}`enter code here`
Following worked for me;
$(window).unload(function(event) {
if(event.clientY < 0) {
//do whatever you want when closing the window..
}
});
I have a Button
d3.select("#updatebutton").on("click", function(e) {
try{
$.get('any url', function(data) {
alert('Any Alert Message');
window.location.href = window.location.href;
});
}
catch (e) {
alert('Error: ' + e);
}
}
where i want to do certain actions on the button click event:
app.get('any url', function(req, res, next) {
try{
anyfunction();
}
catch(e) {
alert('Error');
}
});
It is working fine on normal web browser, however if I open my webpage on a mobile device, it seems that the click event is never called and nothing happens. Is this a jQuery Problem or am I missing something?
The Code is running on a node.js Server.
Hope anyone can help.
UPDATE:
I'm using jade as rendering-engine for HTML. My Button looks like the following:
div#updatebutton
i.fa.fa-repeat.fa-lg
| 'some description'
Try with touchstart event.
UPDATE
Please check.
var myButton = d3.select("#updatebutton");
myButton.on("touchstart", onDown);
function onDown() {
alert("Work");
try{
$.get('any url', function(data) {
alert('Any Alert Message');
window.location.href = window.location.href;
});
}
catch (e) {
alert('Error: ' + e);
}
}
You can detect user device using navigator object. Refer this
If device is touch enabled then use touchstart/touchend events or use click events for desktops(click events should work in mobile browsers too, can not guess the reason by going through the provided code)
Try this:
function is_touch_device() {
return (('ontouchstart' in window) || (navigator.MaxTouchPoints > 0) || (navigator.msMaxTouchPoints > 0));
}
var myButton = d3.select("#updatebutton");
var myEvent = is_touch_device() ? 'touchend' : 'click';
myButton.on(myEvent, onDown);
function onDown() {
$.get('any url', function(data) {
alert('Any Alert Message');
window.location.reload(); //better way to reload the page
}).fail(function(error) {
console.log(error);
});
}
Hi i want to detect browser refresh alone in javascript. The below code am using is detecting the browser close as well as refresh, back etc.
window.onbeforeunload = function (evt) {
var message = 'Are you sure you want to leave?';
console.log(evt);
console.log(window.event);
console.log(event);
if (typeof evt == 'undefined') {
evt = window.event;
}
if (evt) {
evt.returnValue = message;
}
return evt;
}
You can save the current time to session storage from onbeforeunload, then when the page loads look in session storage for a time and, if you find one and it's within (say) a couple of seconds, assume it's a refresh.
window.onbeforeunload = function() {
sessionStorage.setItem("left", Date.now());
};
and elsewhere, in code that runs when the page loads:
var left = sessionStorage.getItem("left");
if (left && (Date.now() - left) < 2000) {
// Refreshed
}
Full example (live copy):
(function() {
"use strict";
window.onbeforeunload = function() {
sessionStorage.setItem("left", Date.now());
};
var left = sessionStorage.getItem("left");
if (left && (Date.now() - left) < 2000) {
// Refreshed
display("Refreshed");
} else {
// Freshly loaded
}
})();
Hi i want to detect browser refresh alone in javascript. The below code am using is detecting the browser close as well as refresh, back etc.
window.onbeforeunload = function (evt) {
var message = 'Are you sure you want to leave?';
console.log(evt);
console.log(window.event);
console.log(event);
if (typeof evt == 'undefined') {
evt = window.event;
}
if (evt) {
evt.returnValue = message;
}
return evt;
}
You can save the current time to session storage from onbeforeunload, then when the page loads look in session storage for a time and, if you find one and it's within (say) a couple of seconds, assume it's a refresh.
window.onbeforeunload = function() {
sessionStorage.setItem("left", Date.now());
};
and elsewhere, in code that runs when the page loads:
var left = sessionStorage.getItem("left");
if (left && (Date.now() - left) < 2000) {
// Refreshed
}
Full example (live copy):
(function() {
"use strict";
window.onbeforeunload = function() {
sessionStorage.setItem("left", Date.now());
};
var left = sessionStorage.getItem("left");
if (left && (Date.now() - left) < 2000) {
// Refreshed
display("Refreshed");
} else {
// Freshly loaded
}
})();