Object doesnt support property or method "attachevent"

Object doesnt support property or method "attachevent" - javascript

I'm facing the subjected issue while launching IE 11 in selenium.jar.
I googled and found some solution like IE 11 needs AttachEvent handler instead of attach event in the js file. but i dont know how to modify since i'm new to js. Can someone please let me know how to do the changes.
Code below.
IEBrowserBot.prototype.modifySeparateTestWindowToDetectPageLoads = function(windowObject) {
this.pageUnloading = false;
var self = this;
var pageUnloadDetector = function() {
self.pageUnloading = true;
};
windowObject.attachEvent("onbeforeunload", pageUnloadDetector);
BrowserBot.prototype.modifySeparateTestWindowToDetectPageLoads.call(this, windowObject);
};
IEBrowserBot.prototype._fireEventOnElement = function(eventType, element, clientX, clientY) {
var win = this.getCurrentWindow();
triggerEvent(element, 'focus', false);
var wasChecked = element.checked;
// Set a flag that records if the page will unload - this isn't always accurate, because
// <a href="javascript:alert('foo'):"> triggers the onbeforeunload event, even thought the page won't unload
var pageUnloading = false;
var pageUnloadDetector = function() {
pageUnloading = true;
};
win.attachEvent("onbeforeunload", pageUnloadDetector);
this._modifyElementTarget(element);
if (element[eventType]) {
element[eventType]();
}
else {
this.browserbot.triggerMouseEvent(element, eventType, true, clientX, clientY);
}
// If the page is going to unload - still attempt to fire any subsequent events.
// However, we can't guarantee that the page won't unload half way through, so we need to handle exceptions.
try {
win.detachEvent("onbeforeunload", pageUnloadDetector);
if (this._windowClosed(win)) {
return;
}

Related

Stop clock when page is not on screen [duplicate]

I have JavaScript that is doing activity periodically. When the user is not looking at the site (i.e., the window or tab does not have focus), it'd be nice to not run.
Is there a way to do this using JavaScript?
My reference point: Gmail Chat plays a sound if the window you're using isn't active.

Since originally writing this answer, a new specification has reached recommendation status thanks to the W3C. The Page Visibility API (on MDN) now allows us to more accurately detect when a page is hidden to the user.
document.addEventListener("visibilitychange", onchange);
Current browser support:
Chrome 13+
Internet Explorer 10+
Firefox 10+
Opera 12.10+ [read notes]
The following code falls back to the less reliable blur/focus method in incompatible browsers:
(function() {
var hidden = "hidden";
// Standards:
if (hidden in document)
document.addEventListener("visibilitychange", onchange);
else if ((hidden = "mozHidden") in document)
document.addEventListener("mozvisibilitychange", onchange);
else if ((hidden = "webkitHidden") in document)
document.addEventListener("webkitvisibilitychange", onchange);
else if ((hidden = "msHidden") in document)
document.addEventListener("msvisibilitychange", onchange);
// IE 9 and lower:
else if ("onfocusin" in document)
document.onfocusin = document.onfocusout = onchange;
// All others:
else
window.onpageshow = window.onpagehide
= window.onfocus = window.onblur = onchange;
function onchange (evt) {
var v = "visible", h = "hidden",
evtMap = {
focus:v, focusin:v, pageshow:v, blur:h, focusout:h, pagehide:h
};
evt = evt || window.event;
if (evt.type in evtMap)
document.body.className = evtMap[evt.type];
else
document.body.className = this[hidden] ? "hidden" : "visible";
}
// set the initial state (but only if browser supports the Page Visibility API)
if( document[hidden] !== undefined )
onchange({type: document[hidden] ? "blur" : "focus"});
})();
onfocusin and onfocusout are required for IE 9 and lower, while all others make use of onfocus and onblur, except for iOS, which uses onpageshow and onpagehide.

I would use jQuery because then all you have to do is this:
$(window).blur(function(){
//your code here
});
$(window).focus(function(){
//your code
});
Or at least it worked for me.

There are 3 typical methods used to determine if the user can see the HTML page, however none of them work perfectly:
The W3C Page Visibility API is supposed to do this (supported since: Firefox 10, MSIE 10, Chrome 13). However, this API only raises events when the browser tab is fully overriden (e.g. when the user changes from one tab to another one). The API does not raise events when the visibility cannot be determined with 100% accuracy (e.g. Alt+Tab to switch to another application).
Using focus/blur based methods gives you a lot of false positive. For example, if the user displays a smaller window on top of the browser window, the browser window will lose the focus (onblur raised) but the user is still able to see it (so it still need to be refreshed). See also http://javascript.info/tutorial/focus
Relying on user activity (mouse move, clicks, key typed) gives you a lot of false positive too. Think about the same case as above, or a user watching a video.
In order to improve the imperfect behaviors described above, I use a combination of the 3 methods: W3C Visibility API, then focus/blur and user activity methods in order to reduce the false positive rate. This allows to manage the following events:
Changing browser tab to another one (100% accuracy, thanks to the W3C Page Visibility API)
Page potentially hidden by another window, e.g. due to Alt+Tab (probabilistic = not 100% accurate)
User attention potentially not focused on the HTML page (probabilistic = not 100% accurate)
This is how it works: when the document lose the focus, the user activity (such as mouse move) on the document is monitored in order to determine if the window is visible or not. The page visibility probability is inversely proportional to the time of the last user activity on the page: if the user makes no activity on the document for a long time, the page is most probably not visible. The code below mimics the W3C Page Visibility API: it behaves the same way but has a small false positive rate. It has the advantage to be multibrowser (tested on Firefox 5, Firefox 10, MSIE 9, MSIE 7, Safari 5, Chrome 9).
<div id="x"></div>
<script>
/**
Registers the handler to the event for the given object.
#param obj the object which will raise the event
#param evType the event type: click, keypress, mouseover, ...
#param fn the event handler function
#param isCapturing set the event mode (true = capturing event, false = bubbling event)
#return true if the event handler has been attached correctly
*/
function addEvent(obj, evType, fn, isCapturing){
if (isCapturing==null) isCapturing=false;
if (obj.addEventListener){
// Firefox
obj.addEventListener(evType, fn, isCapturing);
return true;
} else if (obj.attachEvent){
// MSIE
var r = obj.attachEvent('on'+evType, fn);
return r;
} else {
return false;
}
}
// register to the potential page visibility change
addEvent(document, "potentialvisilitychange", function(event) {
document.getElementById("x").innerHTML+="potentialVisilityChange: potentialHidden="+document.potentialHidden+", document.potentiallyHiddenSince="+document.potentiallyHiddenSince+" s<br>";
});
// register to the W3C Page Visibility API
var hidden=null;
var visibilityChange=null;
if (typeof document.mozHidden !== "undefined") {
hidden="mozHidden";
visibilityChange="mozvisibilitychange";
} else if (typeof document.msHidden !== "undefined") {
hidden="msHidden";
visibilityChange="msvisibilitychange";
} else if (typeof document.webkitHidden!=="undefined") {
hidden="webkitHidden";
visibilityChange="webkitvisibilitychange";
} else if (typeof document.hidden !=="hidden") {
hidden="hidden";
visibilityChange="visibilitychange";
}
if (hidden!=null && visibilityChange!=null) {
addEvent(document, visibilityChange, function(event) {
document.getElementById("x").innerHTML+=visibilityChange+": "+hidden+"="+document[hidden]+"<br>";
});
}
var potentialPageVisibility = {
pageVisibilityChangeThreshold:3*3600, // in seconds
init:function() {
function setAsNotHidden() {
var dispatchEventRequired=document.potentialHidden;
document.potentialHidden=false;
document.potentiallyHiddenSince=0;
if (dispatchEventRequired) dispatchPageVisibilityChangeEvent();
}
function initPotentiallyHiddenDetection() {
if (!hasFocusLocal) {
// the window does not has the focus => check for user activity in the window
lastActionDate=new Date();
if (timeoutHandler!=null) {
clearTimeout(timeoutHandler);
}
timeoutHandler = setTimeout(checkPageVisibility, potentialPageVisibility.pageVisibilityChangeThreshold*1000+100); // +100 ms to avoid rounding issues under Firefox
}
}
function dispatchPageVisibilityChangeEvent() {
unifiedVisilityChangeEventDispatchAllowed=false;
var evt = document.createEvent("Event");
evt.initEvent("potentialvisilitychange", true, true);
document.dispatchEvent(evt);
}
function checkPageVisibility() {
var potentialHiddenDuration=(hasFocusLocal || lastActionDate==null?0:Math.floor((new Date().getTime()-lastActionDate.getTime())/1000));
document.potentiallyHiddenSince=potentialHiddenDuration;
if (potentialHiddenDuration>=potentialPageVisibility.pageVisibilityChangeThreshold && !document.potentialHidden) {
// page visibility change threshold raiched => raise the even
document.potentialHidden=true;
dispatchPageVisibilityChangeEvent();
}
}
var lastActionDate=null;
var hasFocusLocal=true;
var hasMouseOver=true;
document.potentialHidden=false;
document.potentiallyHiddenSince=0;
var timeoutHandler = null;
addEvent(document, "pageshow", function(event) {
document.getElementById("x").innerHTML+="pageshow/doc:<br>";
});
addEvent(document, "pagehide", function(event) {
document.getElementById("x").innerHTML+="pagehide/doc:<br>";
});
addEvent(window, "pageshow", function(event) {
document.getElementById("x").innerHTML+="pageshow/win:<br>"; // raised when the page first shows
});
addEvent(window, "pagehide", function(event) {
document.getElementById("x").innerHTML+="pagehide/win:<br>"; // not raised
});
addEvent(document, "mousemove", function(event) {
lastActionDate=new Date();
});
addEvent(document, "mouseover", function(event) {
hasMouseOver=true;
setAsNotHidden();
});
addEvent(document, "mouseout", function(event) {
hasMouseOver=false;
initPotentiallyHiddenDetection();
});
addEvent(window, "blur", function(event) {
hasFocusLocal=false;
initPotentiallyHiddenDetection();
});
addEvent(window, "focus", function(event) {
hasFocusLocal=true;
setAsNotHidden();
});
setAsNotHidden();
}
}
potentialPageVisibility.pageVisibilityChangeThreshold=4; // 4 seconds for testing
potentialPageVisibility.init();
</script>
Since there is currently no working cross-browser solution without false positive, you should better think twice about disabling periodical activity on your web site.

Using : Page Visibility API
document.addEventListener( 'visibilitychange' , function() {
if (document.hidden) {
console.log('bye');
} else {
console.log('well back');
}
}, false );
Can i use ? http://caniuse.com/#feat=pagevisibility

I started off using the community wiki answer, but realised that it wasn't detecting alt-tab events in Chrome. This is because it uses the first available event source, and in this case it's the page visibility API, which in Chrome seems to not track alt-tabbing.
I decided to modify the script a bit to keep track of all possible events for page focus changes. Here's a function you can drop in:
function onVisibilityChange(callback) {
var visible = true;
if (!callback) {
throw new Error('no callback given');
}
function focused() {
if (!visible) {
callback(visible = true);
}
}
function unfocused() {
if (visible) {
callback(visible = false);
}
}
// Standards:
if ('hidden' in document) {
visible = !document.hidden;
document.addEventListener('visibilitychange',
function() {(document.hidden ? unfocused : focused)()});
}
if ('mozHidden' in document) {
visible = !document.mozHidden;
document.addEventListener('mozvisibilitychange',
function() {(document.mozHidden ? unfocused : focused)()});
}
if ('webkitHidden' in document) {
visible = !document.webkitHidden;
document.addEventListener('webkitvisibilitychange',
function() {(document.webkitHidden ? unfocused : focused)()});
}
if ('msHidden' in document) {
visible = !document.msHidden;
document.addEventListener('msvisibilitychange',
function() {(document.msHidden ? unfocused : focused)()});
}
// IE 9 and lower:
if ('onfocusin' in document) {
document.onfocusin = focused;
document.onfocusout = unfocused;
}
// All others:
window.onpageshow = window.onfocus = focused;
window.onpagehide = window.onblur = unfocused;
};
Use it like this:
onVisibilityChange(function(visible) {
console.log('the page is now', visible ? 'focused' : 'unfocused');
});
This version listens for all the different visibility events and fires a callback if any of them causes a change. The focused and unfocused handlers make sure that the callback isn't called multiple times if multiple APIs catch the same visibility change.

There is a neat library available on GitHub:
https://github.com/serkanyersen/ifvisible.js
Example:
// If page is visible right now
if( ifvisible.now() ){
// Display pop-up
openPopUp();
}
I've tested version 1.0.1 on all browsers I have and can confirm that it works with:
IE9, IE10
FF 26.0
Chrome 34.0
... and probably all newer versions.
Doesn't fully work with:
IE8 - always indicate that tab/window is currently active (.now() always returns true for me)

I create a Comet Chat for my app, and when I receive a message from another user I use:
if(new_message){
if(!document.hasFocus()){
audio.play();
document.title="Have new messages";
}
else{
audio.stop();
document.title="Application Name";
}
}

This is really tricky. There seems to be no solution given the following requirements.
The page includes iframes that you have no control over
You want to track visibility state change regardless of the change being triggered by a TAB change (ctrl+tab) or a window change (alt+tab)
This happens because:
The page Visibility API can reliably tell you of a tab change (even with iframes), but it can't tell you when the user changes windows.
Listening to window blur/focus events can detect alt+tabs and ctrl+tabs, as long as the iframe doesn't have focus.
Given these restrictions, it is possible to implement a solution that combines
- The page Visibility API
- window blur/focus
- document.activeElement
That is able to:
1) ctrl+tab when parent page has focus: YES
2) ctrl+tab when iframe has focus: YES
3) alt+tab when parent page has focus: YES
4) alt+tab when iframe has focus: NO <-- bummer
When the iframe has focus, your blur/focus events don't get invoked at all, and the page Visibility API won't trigger on alt+tab.
I built upon #AndyE's solution and implemented this (almost good) solution here:
https://dl.dropboxusercontent.com/u/2683925/estante-components/visibility_test1.html
(sorry, I had some trouble with JSFiddle).
This is also available on Github: https://github.com/qmagico/estante-components
This works on chrome/chromium.
It kind works on firefox, except that it doesn't load the iframe contents (any idea why?)
Anyway, to resolve the last problem (4), the only way you can do that is to listen for blur/focus events on the iframe.
If you have some control over the iframes, you can use the postMessage API to do that.
https://dl.dropboxusercontent.com/u/2683925/estante-components/visibility_test2.html
I still haven't tested this with enough browsers.
If you can find more info about where this doesn't work, please let me know in the comments below.

var visibilityChange = (function (window) {
var inView = false;
return function (fn) {
window.onfocus = window.onblur = window.onpageshow = window.onpagehide = function (e) {
if ({focus:1, pageshow:1}[e.type]) {
if (inView) return;
fn("visible");
inView = true;
} else if (inView) {
fn("hidden");
inView = false;
}
};
};
}(this));
visibilityChange(function (state) {
console.log(state);
});
http://jsfiddle.net/ARTsinn/JTxQY/

this works for me on chrome 67, firefox 67,
if(!document.hasFocus()) {
// do stuff
}

this worked for me
document.addEventListener("visibilitychange", function() {
document.title = document.hidden ? "I'm away" : "I'm here";
});
demo: https://iamsahilralkar.github.io/document-hidden-demo/

This works in all modern browsers:
when changing tabs
when changing windows(Alt+Tab)
when maximizing another program from the taskbar
var eventName;
var visible = true;
var propName = "hidden";
if (propName in document) eventName = "visibilitychange";
else if ((propName = "msHidden") in document) eventName = "msvisibilitychange";
else if ((propName = "mozHidden") in document) eventName = "mozvisibilitychange";
else if ((propName = "webkitHidden") in document) eventName = "webkitvisibilitychange";
if (eventName) document.addEventListener(eventName, handleChange);
if ("onfocusin" in document) document.onfocusin = document.onfocusout = handleChange; //IE 9
window.onpageshow = window.onpagehide = window.onfocus = window.onblur = handleChange;// Changing tab with alt+tab
// Initialize state if Page Visibility API is supported
if (document[propName] !== undefined) handleChange({ type: document[propName] ? "blur" : "focus" });
function handleChange(evt) {
evt = evt || window.event;
if (visible && (["blur", "focusout", "pagehide"].includes(evt.type) || (this && this[propName]))){
visible = false;
console.log("Out...")
}
else if (!visible && (["focus", "focusin", "pageshow"].includes(evt.type) || (this && !this[propName]))){
visible = true;
console.log("In...")
}
}

In HTML 5 you could also use:
onpageshow: Script to be run when the window becomes visible
onpagehide: Script to be run when the window is hidden
See:
https://developer.mozilla.org/en-US/docs/Web/Events/pageshow
https://developer.mozilla.org/en-US/docs/Web/Events/pagehide

u can use :
(function () {
var requiredResolution = 10; // ms
var checkInterval = 1000; // ms
var tolerance = 20; // percent
var counter = 0;
var expected = checkInterval / requiredResolution;
//console.log('expected:', expected);
window.setInterval(function () {
counter++;
}, requiredResolution);
window.setInterval(function () {
var deviation = 100 * Math.abs(1 - counter / expected);
// console.log('is:', counter, '(off by', deviation , '%)');
if (deviation > tolerance) {
console.warn('Timer resolution not sufficient!');
}
counter = 0;
}, checkInterval);
})();

A slightly more complicated way would be to use setInterval() to check mouse position and compare to last check. If the mouse hasn't moved in a set amount of time, the user is probably idle.
This has the added advantage of telling if the user is idle, instead of just checking if the window is not active.
As many people have pointed out, this is not always a good way to check whether the user or browser window is idle, as the user might not even be using the mouse or is watching a video, or similar. I am just suggesting one possible way to check for idle-ness.

This is an adaptation of the answer from Andy E.
This will do a task e.g. refresh the page every 30 seconds,
but only if the page is visible and focused.
If visibility can't be detected, then only focus will be used.
If the user focuses the page, then it will update immediately
The page won't update again until 30 seconds after any ajax call
var windowFocused = true;
var timeOut2 = null;
$(function(){
$.ajaxSetup ({
cache: false
});
$("#content").ajaxComplete(function(event,request, settings){
set_refresh_page(); // ajax call has just been made, so page doesn't need updating again for 30 seconds
});
// check visibility and focus of window, so as not to keep updating unnecessarily
(function() {
var hidden, change, vis = {
hidden: "visibilitychange",
mozHidden: "mozvisibilitychange",
webkitHidden: "webkitvisibilitychange",
msHidden: "msvisibilitychange",
oHidden: "ovisibilitychange" /* not currently supported */
};
for (hidden in vis) {
if (vis.hasOwnProperty(hidden) && hidden in document) {
change = vis[hidden];
break;
}
}
document.body.className="visible";
if (change){ // this will check the tab visibility instead of window focus
document.addEventListener(change, onchange,false);
}
if(navigator.appName == "Microsoft Internet Explorer")
window.onfocus = document.onfocusin = document.onfocusout = onchangeFocus
else
window.onfocus = window.onblur = onchangeFocus;
function onchangeFocus(evt){
evt = evt || window.event;
if (evt.type == "focus" || evt.type == "focusin"){
windowFocused=true;
}
else if (evt.type == "blur" || evt.type == "focusout"){
windowFocused=false;
}
if (evt.type == "focus"){
update_page(); // only update using window.onfocus, because document.onfocusin can trigger on every click
}
}
function onchange () {
document.body.className = this[hidden] ? "hidden" : "visible";
update_page();
}
function update_page(){
if(windowFocused&&(document.body.className=="visible")){
set_refresh_page(1000);
}
}
})();
set_refresh_page();
})
function get_date_time_string(){
var d = new Date();
var dT = [];
dT.push(d.getDate());
dT.push(d.getMonth())
dT.push(d.getFullYear());
dT.push(d.getHours());
dT.push(d.getMinutes());
dT.push(d.getSeconds());
dT.push(d.getMilliseconds());
return dT.join('_');
}
function do_refresh_page(){
// do tasks here
// e.g. some ajax call to update part of the page.
// (date time parameter will probably force the server not to cache)
// $.ajax({
// type: "POST",
// url: "someUrl.php",
// data: "t=" + get_date_time_string()+"&task=update",
// success: function(html){
// $('#content').html(html);
// }
// });
}
function set_refresh_page(interval){
interval = typeof interval !== 'undefined' ? interval : 30000; // default time = 30 seconds
if(timeOut2 != null) clearTimeout(timeOut2);
timeOut2 = setTimeout(function(){
if((document.body.className=="visible")&&windowFocused){
do_refresh_page();
}
set_refresh_page();
}, interval);
}

For a solution without jQuery check out Visibility.js which provides information about three page states
visible ... page is visible
hidden ... page is not visible
prerender ... page is being prerendered by the browser
and also convenience-wrappers for setInterval
/* Perform action every second if visible */
Visibility.every(1000, function () {
action();
});
/* Perform action every second if visible, every 60 sec if not visible */
Visibility.every(1000, 60*1000, function () {
action();
});
A fallback for older browsers (IE < 10; iOS < 7) is also available

The Chromium team is currently developing the Idle Detection API. It is available as an origin trial since Chrome 88, which is already the 2nd origin trial for this feature. An earlier origin trial went from Chrome 84 through Chrome 86.
It can also be enabled via a flag:
Enabling via chrome://flags
To experiment with the Idle Detection API locally, without an
origin trial token, enable the
#enable-experimental-web-platform-features flag in
chrome://flags.
A demo can be found here:
https://idle-detection.glitch.me/
It has to be noted though that this API is permission-based (as it should be, otherwise this could be misused to monitor a user's behaviour!).

For angular.js, here is a directive (based on the accepted answer) that will allow your controller to react to a change in visibility:
myApp.directive('reactOnWindowFocus', function($parse) {
return {
restrict: "A",
link: function(scope, element, attrs) {
var hidden = "hidden";
var currentlyVisible = true;
var functionOrExpression = $parse(attrs.reactOnWindowFocus);
// Standards:
if (hidden in document)
document.addEventListener("visibilitychange", onchange);
else if ((hidden = "mozHidden") in document)
document.addEventListener("mozvisibilitychange", onchange);
else if ((hidden = "webkitHidden") in document)
document.addEventListener("webkitvisibilitychange", onchange);
else if ((hidden = "msHidden") in document)
document.addEventListener("msvisibilitychange", onchange);
else if ("onfocusin" in document) {
// IE 9 and lower:
document.onfocusin = onshow;
document.onfocusout = onhide;
} else {
// All others:
window.onpageshow = window.onfocus = onshow;
window.onpagehide = window.onblur = onhide;
}
function onchange (evt) {
//occurs both on leaving and on returning
currentlyVisible = !currentlyVisible;
doSomethingIfAppropriate();
}
function onshow(evt) {
//for older browsers
currentlyVisible = true;
doSomethingIfAppropriate();
}
function onhide(evt) {
//for older browsers
currentlyVisible = false;
doSomethingIfAppropriate();
}
function doSomethingIfAppropriate() {
if (currentlyVisible) {
//trigger angular digest cycle in this scope
scope.$apply(function() {
functionOrExpression(scope);
});
}
}
}
};
});
You can use it like this example: <div react-on-window-focus="refresh()">, where refresh() is a scope function in the scope of whatever Controller is in scope.

Simple/immediate check:
if(document.hidden) {
// do something
}
Visibility change event:
document.addEventListener("visibilitychange", function() {
console.log(document.visibilityState); // "hidden" or "visible"
}, false);
Promise-based event:
// An `await`able function that resolves when page visibility changes:
function visibilityChange(state="") {
return new Promise(resolve => {
document.addEventListener("visibilitychange", function() {
if(!state || document.visibilityState === state) {
resolve(document.visibilityState);
document.removeEventListener("visibilitychange", arguments.callee);
}
});
});
}
// Use it like this:
await visibilityChange();
console.log(document.visibilityState);
// Or wait for page to become...
await visibilityChange("visible");
await visibilityChange("hidden");
(Note: I was the one who added the latter two solutions into this answer, since that question is now closed and I couldn't add my own answer. Just in case someone thinks I've copied them from that post without crediting.)

If you want to act on whole browser blur:
As I commented, if browser lose focus none of the suggested events fire. My idea is to count up in a loop and reset the counter if an event fire. If the counter reach a limit I do a location.href to an other page. This also fire if you work on dev-tools.
var iput=document.getElementById("hiddenInput");
,count=1
;
function check(){
count++;
if(count%2===0){
iput.focus();
}
else{
iput.blur();
}
iput.value=count;
if(count>3){
location.href="http://Nirwana.com";
}
setTimeout(function(){check()},1000);
}
iput.onblur=function(){count=1}
iput.onfocus=function(){count=1}
check();
This is a draft successful tested on FF.

I reread the #daniel-buckmaster version
I didn't make the multiple attempt, however, the code seems more elegant to me...
// on-visibility-change.js v1.0.1, based on https://stackoverflow.com/questions/1060008/is-there-a-way-to-detect-if-a-browser-window-is-not-currently-active#38710376
function onVisibilityChange(callback) {
let d = document;
let visible = true;
let prefix;
if ('hidden' in d) {
prefix = 'h';
} else if ('webkitHidden' in d) {
prefix = 'webkitH';
} else if ('mozHidden' in d) {
prefix = 'mozH';
} else if ('msHidden' in d) {
prefix = 'msH';
} else if ('onfocusin' in d) { // ie 9 and lower
d.onfocusin = focused;
d.onfocusout = unfocused;
} else { // others
window.onpageshow = window.onfocus = focused;
window.onpagehide = window.onblur = unfocused;
};
if (prefix) {
visible = !d[prefix + 'idden'];
d.addEventListener(prefix.substring(0, prefix.length - 1) + 'visibilitychange', function() {
(d[prefix + 'idden'] ? unfocused : focused)();
});
};
function focused() {
if (!visible) {
callback(visible = true);
};
};
function unfocused() {
if (visible) {
callback(visible = false);
};
};
};

Here is a solid, modern solution. (Short a sweet 👌🏽)
document.addEventListener("visibilitychange", () => {
console.log( document.hasFocus() )
})
This will setup a listener to trigger when any visibility event is fired which could be a focus or blur.

my code
let browser_active = ((typeof document.hasFocus != 'undefined' ? document.hasFocus() : 1) ? 1 : 0);
if (!browser_active) {
// active
}

FireFox different onchange behavior than Webkit/IE

Is anyone able to explain this?
Basically when you're in firefox, and you hit tab, the "console.log" in the onchange gets called but not in Chrome/Safari (webkit) or IE.
function initLookup(id) {
var lookupElement = document.getElementById(id);
var lookup = new Lookup(lookupElement);
lookupElement.lookup = lookup;
}
function Lookup(lookupElement) {
this.doKeyDown = doKeyDown;
this.setLookup = setLookup;
this.inputElement = lookupElement;
this.inputElement.onkeydown = this.doKeyDown;
var self = this;
function setLookup() {
self.inputElement.value = 'asdf';
}
function doKeyDown(event) {
if(event.keyCode == 9) {
setLookup();
}
}
}
initLookup("one");
And a JS fiddle working example:
http://jsfiddle.net/pj9Gf/5/

Gecko differs from IE (and apparently Webkit), in that the change event is fired after the blur event had been fired.
By setting the value on TAB key-press, you're effectively preventing the change from being applied, as the change trigger is defined by a difference between the values detected on focus and on blur.
Reference
element.onchange on Mozilla Developer Network

Is it possible to listen for keydown and keyup while resizing window

I'm trying to detect keydown and keyup, while the window is being resized. What I've tried so far, only fires the key events after the resize is finished.
$(window).resize(function(){
console.log("resizing");
});
$(window).keydown(function(e){
$("#key").css("background","green");
});
$(window).keyup(function(e){
$("#key").css("background","red");
});

Okay, so part of the problem you may be running into here is that keydown isn't an on or off thing, it's a fire-constantly thing.
The same is true of onresize.
As you resize the window the event gets called over and over.
Also, because JS isn't multithreaded, only one of these events is going to happen at one time.
The other event is going to be queued up to run immediately after the other event finishes.
So what you actually want is a state machine that one event sets, and the other event checks.
Quick examples:
var BrowserWindow = { width : 0, height : 0, prevWidth : 0, prevHeight : 0 };
window.onresize = function (e) {
/* set prevWidth/prevHeight, get new width/height */
};
window.onkeydown = function (e) {
if (BrowserWindow.prevWidth !== BrowserWindow.width) { /*...*/ }
};
That would work (except that it would only work when the screen was actively being stretched... so it wouldn't happen in the case where the key was down and the edge of the window was being held but not dragged (which might lead to flickering if the browser fires keydown events more-frequently than resize).
The more appropriate answer would likely be to go the other way:
var Keyboard = {
currentKeys : {},
previousKeys : {}
};
window.onkeydown = function (e) { Keyboard.currentKeys[e.keyCode] = true; };
window.onkeyup = function (e) { delete Keyboard.currentKeys[e.keyCode]; };
window.onresize = function (e) {
var key = <X>,
state = "";
state = Keyboard.currentKeys[key] && !Keyboard.previousKeys[key]
? "pressed"
: !Keyboard.currentKeys[key] && Keyboard.previousKeys[key]
? "released"
: Keyboard.currentKeys[key] && Keyboard.previousKeys[key]
? "held"
: "off";
Keyboard.previousKeys = Keyboard.currentKeys;
doSomething(state);
};
This is less than perfect from an architecture standpoint, but is more along the idea of what you'd have to do in another environment.

How to detect if URL has changed after hash in JavaScript

How can I check if a URL has changed in JavaScript? For example, websites like GitHub, which use AJAX, will append page information after a # symbol to create a unique URL without reloading the page. What is the best way to detect if this URL changes?
Is the onload event called again?
Is there an event handler for the URL?
Or must the URL be checked every second to detect a change?

I wanted to be able to add locationchange event listeners. After the modification below, we'll be able to do it, like this
window.addEventListener('locationchange', function () {
console.log('location changed!');
});
In contrast, window.addEventListener('hashchange',() => {}) would only fire if the part after a hashtag in a url changes, and window.addEventListener('popstate',() => {}) doesn't always work.
This modification, similar to Christian's answer, modifies the history object to add some functionality.
By default, before these modifications, there's a popstate event, but there are no events for pushstate, and replacestate.
This modifies these three functions so that all fire a custom locationchange event for you to use, and also pushstate and replacestate events if you want to use those.
These are the modifications:
(() => {
let oldPushState = history.pushState;
history.pushState = function pushState() {
let ret = oldPushState.apply(this, arguments);
window.dispatchEvent(new Event('pushstate'));
window.dispatchEvent(new Event('locationchange'));
return ret;
};
let oldReplaceState = history.replaceState;
history.replaceState = function replaceState() {
let ret = oldReplaceState.apply(this, arguments);
window.dispatchEvent(new Event('replacestate'));
window.dispatchEvent(new Event('locationchange'));
return ret;
};
window.addEventListener('popstate', () => {
window.dispatchEvent(new Event('locationchange'));
});
})();
Note, we're creating a closure, to save the old function as part of the new one, so that it gets called whenever the new one is called.

In modern browsers (IE8+, FF3.6+, Chrome), you can just listen to the hashchange event on window.
In some old browsers, you need a timer that continually checks location.hash. If you're using jQuery, there is a plugin that does exactly that.
Example
Below I undo any URL change, to keep just the scrolling:
<script type="text/javascript">
if (window.history) {
var myOldUrl = window.location.href;
window.addEventListener('hashchange', function(){
window.history.pushState({}, null, myOldUrl);
});
}
</script>
Note that above used history-API is available in Chrome, Safari, Firefox 4+, and Internet Explorer 10pp4+

window.onhashchange = function() {
//code
}
window.onpopstate = function() {
//code
}
or
window.addEventListener('hashchange', function() {
//code
});
window.addEventListener('popstate', function() {
//code
});
with jQuery
$(window).bind('hashchange', function() {
//code
});
$(window).bind('popstate', function() {
//code
});

EDIT after a bit of researching:
It somehow seems that I have been fooled by the documentation present on Mozilla docs. The popstate event (and its callback function onpopstate) are not triggered whenever the pushState() or replaceState() are called in code. Therefore the original answer does not apply in all cases.
However there is a way to circumvent this by monkey-patching the functions according to #alpha123:
var pushState = history.pushState;
history.pushState = function () {
pushState.apply(history, arguments);
fireEvents('pushState', arguments); // Some event-handling function
};
Original answer
Given that the title of this question is "How to detect URL change" the answer, when you want to know when the full path changes (and not just the hash anchor), is that you can listen for the popstate event:
window.onpopstate = function(event) {
console.log("location: " + document.location + ", state: " + JSON.stringify(event.state));
};
Reference for popstate in Mozilla Docs
Currently (Jan 2017) there is support for popstate from 92% of browsers worldwide.

With jquery (and a plug-in) you can do
$(window).bind('hashchange', function() {
/* things */
});
http://benalman.com/projects/jquery-hashchange-plugin/
Otherwise yes, you would have to use setInterval and check for a change in the hash event (window.location.hash)
Update! A simple draft
function hashHandler(){
this.oldHash = window.location.hash;
this.Check;
var that = this;
var detect = function(){
if(that.oldHash!=window.location.hash){
alert("HASH CHANGED - new has" + window.location.hash);
that.oldHash = window.location.hash;
}
};
this.Check = setInterval(function(){ detect() }, 100);
}
var hashDetection = new hashHandler();

Add a hash change event listener!
window.addEventListener('hashchange', function(e){console.log('hash changed')});
Or, to listen to all URL changes:
window.addEventListener('popstate', function(e){console.log('url changed')});
This is better than something like the code below because only one thing can exist in window.onhashchange and you'll possibly be overwriting someone else's code.
// Bad code example
window.onhashchange = function() {
// Code that overwrites whatever was previously in window.onhashchange
}

this solution worked for me:
function checkURLchange(){
if(window.location.href != oldURL){
alert("url changed!");
oldURL = window.location.href;
}
}
var oldURL = window.location.href;
setInterval(checkURLchange, 1000);

None of these seem to work when a link is clicked that which redirects you to a different page on the same domain. Hence, I made my own solution:
let pathname = location.pathname;
window.addEventListener("click", function() {
if (location.pathname != pathname) {
pathname = location.pathname;
// code
}
});
Edit: You can also check for the popstate event (if a user goes back a page)
window.addEventListener("popstate", function() {
// code
});
Best wishes,
Calculus

If none of the window events are working for you (as they aren't in my case), you can also use a MutationObserver that looks at the root element (non-recursively).
// capture the location at page load
let currentLocation = document.location.href;
const observer = new MutationObserver((mutationList) => {
if (currentLocation !== document.location.href) {
// location changed!
currentLocation = document.location.href;
// (do your event logic here)
}
});
observer.observe(
document.getElementById('root'),
{
childList: true,
// important for performance
subtree: false
});
This may not always be feasible, but typically, if the URL changes, the root element's contents change as well.
I have not profiled, but theoretically this has less overhead than a timer because the Observer pattern is typically implemented so that it just loops through the subscriptions when a change occurs. We only added one subscription here. The timer on the other hand would have to check very frequently in order to ensure that the event was triggered immediately after URL change.
Also, this has a good chance of being more reliable than a timer since it eliminates timing issues.

Although an old question, the Location-bar project is very useful.
var LocationBar = require("location-bar");
var locationBar = new LocationBar();
// listen to all changes to the location bar
locationBar.onChange(function (path) {
console.log("the current url is", path);
});
// listen to a specific change to location bar
// e.g. Backbone builds on top of this method to implement
// it's simple parametrized Backbone.Router
locationBar.route(/some\-regex/, function () {
// only called when the current url matches the regex
});
locationBar.start({
pushState: true
});
// update the address bar and add a new entry in browsers history
locationBar.update("/some/url?param=123");
// update the address bar but don't add the entry in history
locationBar.update("/some/url", {replace: true});
// update the address bar and call the `change` callback
locationBar.update("/some/url", {trigger: true});

To listen to url changes, see below:
window.onpopstate = function(event) {
console.log("location: " + document.location + ", state: " + JSON.stringify(event.state));
};
Use this style if you intend to stop/remove listener after some certain condition.
window.addEventListener('popstate', function(e) {
console.log('url changed')
});

The answer below comes from here(with old javascript syntax(no arrow function, support IE 10+)):
https://stackoverflow.com/a/52809105/9168962
(function() {
if (typeof window.CustomEvent === "function") return false; // If not IE
function CustomEvent(event, params) {
params = params || {bubbles: false, cancelable: false, detail: null};
var evt = document.createEvent("CustomEvent");
evt.initCustomEvent(event, params.bubbles, params.cancelable, params.detail);
return evt;
}
window.CustomEvent = CustomEvent;
})();
(function() {
history.pushState = function (f) {
return function pushState() {
var ret = f.apply(this, arguments);
window.dispatchEvent(new CustomEvent("pushState"));
window.dispatchEvent(new CustomEvent("locationchange"));
return ret;
};
}(history.pushState);
history.replaceState = function (f) {
return function replaceState() {
var ret = f.apply(this, arguments);
window.dispatchEvent(new CustomEvent("replaceState"));
window.dispatchEvent(new CustomEvent("locationchange"));
return ret;
};
}(history.replaceState);
window.addEventListener("popstate", function() {
window.dispatchEvent(new CustomEvent("locationchange"));
});
})();

While doing a little chrome extension, I faced the same problem with an additionnal problem : Sometimes, the page change but not the URL.
For instance, just go to the Facebook Homepage, and click on the 'Home' button. You will reload the page but the URL won't change (one-page app style).
99% of the time, we are developping websites so we can get those events from Frameworks like Angular, React, Vue etc..
BUT, in my case of a Chrome extension (in Vanilla JS), I had to listen to an event that will trigger for each "page change", which can generally be caught by URL changed, but sometimes it doesn't.
My homemade solution was the following :
listen(window.history.length);
var oldLength = -1;
function listen(currentLength) {
if (currentLength != oldLength) {
// Do your stuff here
}
oldLength = window.history.length;
setTimeout(function () {
listen(window.history.length);
}, 1000);
}
So basically the leoneckert solution, applied to window history, which will change when a page changes in a single page app.
Not rocket science, but cleanest solution I found, considering we are only checking an integer equality here, and not bigger objects or the whole DOM.

Found a working answer in a separate thread:
There's no one event that will always work, and monkey patching the pushState event is pretty hit or miss for most major SPAs.
So smart polling is what's worked best for me. You can add as many event types as you like, but these seem to be doing a really good job for me.
Written for TS, but easily modifiable:
const locationChangeEventType = "MY_APP-location-change";
// called on creation and every url change
export function observeUrlChanges(cb: (loc: Location) => any) {
assertLocationChangeObserver();
window.addEventListener(locationChangeEventType, () => cb(window.location));
cb(window.location);
}
function assertLocationChangeObserver() {
const state = window as any as { MY_APP_locationWatchSetup: any };
if (state.MY_APP_locationWatchSetup) { return; }
state.MY_APP_locationWatchSetup = true;
let lastHref = location.href;
["popstate", "click", "keydown", "keyup", "touchstart", "touchend"].forEach((eventType) => {
window.addEventListener(eventType, () => {
requestAnimationFrame(() => {
const currentHref = location.href;
if (currentHref !== lastHref) {
lastHref = currentHref;
window.dispatchEvent(new Event(locationChangeEventType));
}
})
})
});
}
Usage
observeUrlChanges((loc) => {
console.log(loc.href)
})

I created this event that is very similar to the hashchange event
// onurlchange-event.js v1.0.1
(() => {
const hasNativeEvent = Object.keys(window).includes('onurlchange')
if (!hasNativeEvent) {
let oldURL = location.href
setInterval(() => {
const newURL = location.href
if (oldURL === newURL) {
return
}
const urlChangeEvent = new CustomEvent('urlchange', {
detail: {
oldURL,
newURL
}
})
oldURL = newURL
dispatchEvent(urlChangeEvent)
}, 25)
addEventListener('urlchange', event => {
if (typeof(onurlchange) === 'function') {
onurlchange(event)
}
})
}
})()
Example of use:
window.onurlchange = event => {
console.log(event)
console.log(event.detail.oldURL)
console.log(event.detail.newURL)
}
addEventListener('urlchange', event => {
console.log(event)
console.log(event.detail.oldURL)
console.log(event.detail.newURL)
})

for Chrome 102+ (2022-05-24)
navigation.addEventListener("navigate", e => {
console.log(`navigate ->`,e.destination.url)
});
API references WICG/navigation-api

Look at the jQuery unload function. It handles all the things.
https://api.jquery.com/unload/
The unload event is sent to the window element when the user navigates away from the page. This could mean one of many things. The user could have clicked on a link to leave the page, or typed in a new URL in the address bar. The forward and back buttons will trigger the event. Closing the browser window will cause the event to be triggered. Even a page reload will first create an unload event.
$(window).unload(
function(event) {
alert("navigating");
}
);

window.addEventListener("beforeunload", function (e) {
// do something
}, false);

You are starting a new setInterval at each call, without cancelling the previous one - probably you only meant to have a setTimeout

Enjoy!
var previousUrl = '';
var observer = new MutationObserver(function(mutations) {
if (location.href !== previousUrl) {
previousUrl = location.href;
console.log(`URL changed to ${location.href}`);
}
});

Another simple way you can do this is by adding a click event, through a class name to the anchor tags on the page to detect when it has been clicked, then you can now use the window.location.href to get the url data which you can use to run your ajax request to the server. Simple and Easy.

Detecting when an iframe gets or loses focus

What's the correct way of detecting when an iframe gets or loses focus (i.e. will or will not receive keyboard events)? The following is not working in Fx4:
var iframe = /* my iframe */;
iframe.addEventListener("focus", function() { /* never gets called */ }, false);

You can poll "document.activeElement" to determine if it matches the iframe. Polling isn't ideal, but it works:
function checkFocus() {
if(document.activeElement == document.getElementsByTagName("iframe")[0]) {
console.log('iframe has focus');
} else {
console.log('iframe not focused');
}
}
window.setInterval(checkFocus, 1000);

i know it's old, but i also had the same problem.
i ended up using this little pice of code:
$(document).on('focusout', function(){
setTimeout(function(){
// using the 'setTimout' to let the event pass the run loop
if (document.activeElement instanceof HTMLIFrameElement) {
// Do your logic here..
}
},0);
});

Turns out it's not really possible. I had to change the logic of my page to avoid the need of tracking if the iframe has focus.

How to check when an iframe has been clicked in or out of as well as hover-state.
Note: I would highly recommend you don't choose a polling method and go with an event driven method such as this.
Disclaimer
It is not possible to use the focus or blur events directly on an iframe but you can use them on the window to provide an event driven method of checking the document.activeElement. Thus you can accomplish what you're after.
Although we're now in 2018, my code is being implemented in GTM and tries to be cross browser compatible back to IE 11. This means there's more efficient code if you're utilizing newer ES/ECMAScript features.
Setup
I'm going to take this a few steps further to show that we can also get the iframe's src attribute as well as determine if it's being hovered.
Code
You would ideally need to put this in a document ready event, or at least encapsulate it so that the variables aren't global [maybe use an IIFE]. I did not wrap it in a document ready because it's handled by GTM. It may also depend where you place this or how you're loading it such as in the footer.
https://jsfiddle.net/9285tbsm/9/
I have noticed in the JSFiddle preview that it's already an iframe, sometimes you have to focus it first before events start to capture. Other issues can be that your browser window isn't yet focused either.
// Helpers
var iframeClickedLast;
function eventFromIframe(event) {
var el = event.target;
return el && el.tagName && el.tagName.toLowerCase() == 'iframe';
}
function getIframeSrc(event) {
var el = event.target;
return eventFromIframe(event) ? el.getAttribute('src') : '';
}
// Events
function windowBlurred(e) {
var el = document.activeElement;
if (el.tagName.toLowerCase() == 'iframe') {
console.log('Blurred: iframe CLICKED ON', 'SRC:', el.getAttribute('src'), e);
iframeClickedLast = true;
}
else {
console.log('Blurred', e);
}
}
function windowFocussed(e) {
if (iframeClickedLast) {
var el = document.activeElement;
iframeClickedLast = false;
console.log('Focussed: iframe CLICKED OFF', 'SRC:', el.getAttribute('src'), e);
}
else {
console.log('Focussed', e);
}
}
function iframeMouseOver(e) {
console.log('Mouse Over', 'SRC:', getIframeSrc(e), e);
}
function iframeMouseOut(e) {
console.log('Mouse Out', 'SRC:', getIframeSrc(e), e);
}
// Attach Events
window.addEventListener('focus', windowFocussed, true);
window.addEventListener('blur', windowBlurred, true);
var iframes = document.getElementsByTagName("iframe");
for (var i = 0; i < iframes.length; i++) {
iframes[i].addEventListener('mouseover', iframeMouseOver, true);
iframes[i].addEventListener('mouseout', iframeMouseOut, true);
}

I have solved this by using contentWindow instead of contentDocument.
The good thing about contentWindow is
it works also in case user clicks another window (another application) or another browser tab. If using activeElement, if user clicks away from the entire window to go to another application, then that logic still think the iframe is in focus, while it is not
and we don't need to poll and do a setInterval at all. This uses the normal addEventListener
let iframe = document.getElementsByTagName("iframe")[0];
// or whatever way you do to grab that iFrame, say you have an `id`, then it's even more precise
if(iframe){
iframeWindow = iframe.contentWindow;
iframeWindow.addEventListener('focus', handleIframeFocused);
iframeWindow.addEventListener('blur', handleIframeBlurred);
}
function handleIframeFocused(){
console.log('iframe focused');
// Additional logic that you need to implement here when focused
}
function handleIframeBlurred(){
console.log('iframe blurred');
// Additional logic that you need to implement here when blurred
}

This solution is working for me on both mobile and desktop:
;(function pollForIframe() {
var myIframe = document.querySelector('#my_iframe');
if (!myIframe) return setTimeout(pollForIframe, 50);
window.addEventListener('blur', function () {
if (document.activeElement == myIframe) {
console.log('myIframe clicked!');
}
});
})();

The solution is to inject a javascript event on the parent page like this :
var script = document.createElement('script');
script.type = 'text/javascript';
script.innerHTML =
"document.addEventListener('click', function()" +
"{ if(document.getElementById('iframe')) {" +
// What you want
"}});";
head.appendChild(script);

Here is the code to Detecting when an iframe gets or loses focus
// This code can be used to verify Iframe gets focus/loses.
function CheckFocus(){
if (document.activeElement.id == $(':focus').context.activeElement.id) {
// here do something
}
else{
//do something
}
}

A compact function that accepts callbacks you want to run when iframe gets or loses focus.
/* eslint-disable no-unused-vars */
export default function watchIframeFocus(onFocus, onBlur) {
let iframeClickedLast;
function windowBlurred(e) {
const el = document.activeElement;
if (el.tagName.toLowerCase() == 'iframe') {
iframeClickedLast = true;
onFocus();
}
}
function windowFocussed(e) {
if (iframeClickedLast) {
iframeClickedLast = false;
onBlur();
}
}
window.addEventListener('focus', windowFocussed, true);
window.addEventListener('blur', windowBlurred, true);
}

This might work
document.addEventListener('click', function(event) {
var frame= document.getElementById("yourFrameID");
var isClickInsideFrame = frame.contains(event.target);
if (!isClickInsideFrame ) {
//exec code
}
});

Develop Reference

JavaScript is the programming language of the Web.