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How to turn off passive event listener for mouse wheel scroll

I created a site that will change images from being displayed on mouse scroll. It was working until this morning on my local machine, but suddenly stopped. When I check the dev console I get an error message that says "[Intervention] Unable to preventDefault inside passive event listener due to target being treated as passive. See https://www.chromestatus.com/features/6662647093133312"
I have read the information at the provided url and I still do not understand how I can turn off this feature. In my code I have the following:
var changeImage = function changeImage(event) {
event.preventDefault();
if (brochure.waitForDelay === false) {
window.onwheel = function () {
return false;
};
brochure.waitForDelay = true;
if (event.deltaY < 0) {
scrollUp();
} else {
scrollDown();
}
setTimeout(function () {
brochure.waitForDelay = false;
window.onwheel = function () {
return true;
};
}, 1250);
} else {
return;
}
};
var determineScrollDirection = function determineScrollDirection() {
document.addEventListener('wheel', changeImage, { passive: false });
};
In determineScrollDirection I set the passive as false and tried to call preventDefault in the changeImage function but I still get the same error message.

I was able to fix this issue by removing the following line:
window.onwheel = function () {
return false;
};

Jquery function is starting on click but I need to stop it

I always wonder that onclick functions start to a javascript or jQuery, but How does it stop? Finally, I faced with a function in my learning progress. May you help me to find a solution?
I want to stop this function on another onclick:
function live_preview() {
var icon = document.getElementById('LivePreIcon');
if (icon.classList.contains('fa-eye-slash')) {
icon.classList.remove('fa-eye-slash');
icon.classList.add('fa-eye');
$('#result').keyup(function () {
$('#dialog').html($(this).val());
});
return;
}
if (icon.classList.contains('fa-eye')) {
icon.classList.remove('fa-eye');
icon.classList.add('fa-eye-slash');
// Stop the jquery function here
return;
}
}

var play=0;
function live_preview() {
var icon = document.getElementById('LivePreIcon');
var play;
if(!play){
if (icon.classList.contains('fa-eye-slash')) {
icon.classList.remove('fa-eye-slash');
icon.classList.add('fa-eye');
$('#result').keyup(function () {
$('#dialog').html($(this).val());
play = 1;
});
return;
}
}
else{
if (icon.classList.contains('fa-eye')) {
icon.classList.remove('fa-eye');
icon.classList.add('fa-eye-slash');
play=0;
return false;
// Stop the jquery function here
}
}
}

JS - Window Focus and Bring to front in Firefox

I am trying to set up a tiny script for Firefox that runs in a javascript add-on (Greasemonkey). We have a queue that we monitor for arriving tickets, I coded something that is supposed to refresh the page every 2 minutes and do the following:
if tickets are found by this condition
if (isEmpty($('#incident_table > tbody'))&isEmpty($('#task_table > tbody')))
then I want the following to happen:
- task-bar blinks with a message so it is visible
- if the window is focused it will display "Tickets in the queue!" alert right away
- if the window is not focused, it will wait for 10 seconds, if still not focused - display "Tickets in the queue!" alert and bring the window to front.
I've got the refresh and blinking part, but I cannot get the focus part to work... I've been looking around and I see that Firefox is having some "issues" with window.focus() and all the "bring to front", most of the code below is inspired by stuff I've found on this site.
Any input is appreciated! I am also opened to alternatives - in the end, what this needs to do is refresh, check the condition and notify if I am already looking at it or if it is not focused wait 10 seconds with a "soft notify" (blink) then bring it to the front if I don't notice it.
Regards,
Dan
{
newExcitingAlerts = (function () {
var oldTitle = document.title;
var msg = "***NEW***";
var timeoutId;
var blink = function() { document.title = document.title == msg ? 'Tickets in queue!' : msg; };
var clear = function() {
clearInterval(timeoutId);
document.title = oldTitle;
window.onmousemove = null;
timeoutId = null;
};
return function () {
if (!timeoutId) {
timeoutId = setInterval(blink, 1000);
window.onmousemove = clear;
}
};
}());
$(document).ready(function(){
function isEmpty( el ){
return !$.trim(el.html());
}
if (isEmpty($('#incident_table > tbody'))&isEmpty($('#task_table > tbody'))) {
}
else{
newExcitingAlerts();
}
setTimeout(function() {
location.reload();
}, 120000);
});
}

Here is the alternative I've used, works like a charm. Web API notifications.
document.addEventListener('DOMContentLoaded', function () {
if (Notification.permission !== "granted")
Notification.requestPermission();
});
function notifyMe() {
if (!Notification) {
alert('Desktop notifications not available in your browser. Try Chromium.');
return;
}
if (Notification.permission !== "granted")
Notification.requestPermission();
else {
var notification = new Notification('Tickets in queue!', {
icon: 'http://siliconangle.com/files/2014/05/servicenow-icon.png',
body: "There are new tickets in queue, please acknowledge!",
});
notification.onclick = function () {
window.open("https://cchprod.service-now.com/task_list.do?sysparm_query=assignment_group%3D3139519437b7f1009654261953990e1f^ORassignment_group%3D31de85e337818a00ef8898a543990e99^ORassignment_group%3Da40029e937ec420065aa261953990eb5^ORassignment_group%3De903ad2d37ec420065aa261953990ecb^ORassignment_group%3Dd25fe5323779c24065aa261953990e54^ORassignment_group%3D508639363779c24065aa261953990e29^ORassignment_group%3D51fe5a37379e0a00ef8898a543990ea2^ORassignment_group%3D3d8171b23779c24065aa261953990e21^ORassignment_group%3Decfe5a37379e0a00ef8898a543990e6c^ORassignment_group%3D48c0b9723779c24065aa261953990e5d^ORassignment_group%3De5fde9fe3739c24065aa261953990e75^ORassignment_group%3D15fe5a37379e0a00ef8898a543990e99^ORassignment_group%3D15fe5a37379e0a00ef8898a543990ea7^ORassignment_group%3D1ed3f1f23779c24065aa261953990e47^active%3Dtrue^sys_class_name%3Dincident^ORsys_class_name%3Dsc_req_item^assigned_toISEMPTY&sysparm_first_row=1&sysparm_view=");
};
}
}
{
newExcitingAlerts = (function () {
var oldTitle = document.title;
var msg = "***NEW***";
var timeoutId;
var blink = function() {
document.title = document.title == msg ? 'Tickets in queue!' : msg;
};
var clear = function() {
clearInterval(timeoutId);
document.title = oldTitle;
window.onmousemove = null;
timeoutId = null;
};
return function () {
if (!timeoutId) {
timeoutId = setInterval(blink, 1000);
window.onmousemove = clear;
}
};
}
());
$(document).ready(function () {
function isEmpty(el) {
return !$.trim(el.html());
}
var x = document.getElementById("task_table").getAttribute("grand_total_rows");
if( x != "0" ) {
newExcitingAlerts();
notifyMe();
}
else
{
}
setTimeout(function() {
location.reload();
}
, 120000);
});
}

In Windows operating system you cannot focus the window while the window of another process is focused. You have to use js-ctypes to get around this.
On Mac OS X and Linux, I'm not sure if you can make your process steal focus from another with the normal functions. But if you can't you can for sure use js-ctypes to get the job done.
Here is how to do it in Windows - https://stackoverflow.com/a/32038880/1828637
It is harder on Windows then on OS X and Linux. I have focused windows on all systems using js-ctypes. So if you can't find out how to do with the functions available to you, let me know.

Windows Store Javascript background audio tassk close() method?

I have created a simple Windows 8.1 store app for just playing internet streaming radio. It looks and works good, but I can't upload my app to Windows Store! After validation a get the message like:
WinJS background task
Error Found:
The WinJS background tasks test encountered the
following errors:
App Radio Skovoroda did not call close() in the
background task JavaScript code found in file default.html.
Impact if not fixed: Apps with background tasks that do not call close() can result in draining the battery.
How to fix: Update the background
task to call close().
The point is I do not need to call close(), because it is a radio player, so, it must play in background for a long time! Any ideas? How to do my app pass the validator?
My script code:
(function () {
"use strict";
var app = WinJS.Application;
var activation = Windows.ApplicationModel.Activation;
app.onactivated = function (args) {
if (args.detail.kind === activation.ActivationKind.launch) {
if (args.detail.previousExecutionState !== activation.ApplicationExecutionState.terminated) {
// TODO: This application has been newly launched. Initialize
// your application here.
} else {
// TODO: This application was suspended and then terminated.
// To create a smooth user experience, restore application state here so that it looks like the app never stopped running.
}
args.setPromise(WinJS.UI.processAll());
var buttonMediaControl = document.getElementById("mediaControlButton");
buttonMediaControl.addEventListener("click", playAndStop, false);
//add variables for social buttons
//Facebook
var fbButton = document.getElementById("fbButton");
fbButton.addEventListener("click", goToFbPage, false);
//VKotakte
var vkButton = document.getElementById("vkButton");
vkButton.addEventListener("click", goToVkPage, false);
//Twitter
var twButton = document.getElementById("twButton");
twButton.addEventListener("click", goToTwPage, false);
//Instagram
var igButton = document.getElementById("igButton");
igButton.addEventListener("click", goToIgPage, false);
//YouTube
var ytButton = document.getElementById("ytButton");
ytButton.addEventListener("click", goToYtPage, false);
//TuneIn
var tiButton = document.getElementById("tiButton");
tiButton.addEventListener("click", goToTiPage, false)
// Assign the button object to MediaControls
var systemMediaControls = Windows.Media.SystemMediaTransportControls.getForCurrentView();
systemMediaControls.addEventListener("buttonpressed", systemMediaControlsButtonPressed, false);
systemMediaControls.isPlayEnabled = true;
systemMediaControls.isPauseEnabled = true;
systemMediaControls.isStopEnabled = true;
systemMediaControls.playbackStatus = Windows.Media.MediaPlaybackStatus.closed;
}
};
app.oncheckpoint = function (args) {
};
// Plays the media.
function playMedia() {
var media = document.getElementById("skovorodaStreamingAudio");
media.play();
var statusIcon = document.getElementById("playStopImage");
statusIcon.src = "images/skovoroda_stop_button.png";
var systemMediaControls = Windows.Media.SystemMediaTransportControls.getForCurrentView();
systemMediaControls.playbackStatus = Windows.Media.MediaPlaybackStatus.playing;
}
// Pauses the media.
function pauseMedia() {
var media = document.getElementById("skovorodaStreamingAudio");
media.pause();
var statusIcon = document.getElementById("playStopImage");
statusIcon.src = "images/skovoroda_play_button.png";
var systemMediaControls = Windows.Media.SystemMediaTransportControls.getForCurrentView();
systemMediaControls.playbackStatus = Windows.Media.MediaPlaybackStatus.paused;
}
// Stops the media.
function stopMedia() {
var media = document.getElementById("skovorodaStreamingAudio");
media.pause();
media.currentTime = 0;
}
function playAndStop() {
var myAudio = document.getElementById("skovorodaStreamingAudio");
var statusIcon = document.getElementById("playStopImage");
if (myAudio.paused) {
var systemMediaControls = Windows.Media.SystemMediaTransportControls.getForCurrentView();
systemMediaControls.playbackStatus = Windows.Media.MediaPlaybackStatus.playing;
myAudio.play();
statusIcon.src = "images/skovoroda_stop_button.png";
} else {
var systemMediaControls = Windows.Media.SystemMediaTransportControls.getForCurrentView();
systemMediaControls.playbackStatus = Windows.Media.MediaPlaybackStatus.paused;
myAudio.pause();
statusIcon.src = "images/skovoroda_play_button.png";
}
}
// The media Play event handler.
function mediaPlaying() {
// Update the SystemMediaTransportControl state.
systemMediaControls.playbackStatus = Windows.Media.MediaPlaybackStatus.playing;
}
// The media Pause event handler.
function mediaPaused() {
// Update the SystemMediaTransportControl state.
systemMediaControls.playbackStatus = Windows.Media.MediaPlaybackStatus.paused;
}
// The media Ended event handler.
function mediaEnded() {
// Update the SystemMediaTransportControl state.
systemMediaControls.playbackStatus = Windows.Media.MediaPlaybackStatus.stopped;
}
function goToFbPage() {
window.open("https://www.facebook.com/radioskovoroda?__mref=message_bubble");
}
function goToVkPage() {
window.open("https://vk.com/radioskovoroda");
}
function goToTwPage() {
window.open("https://twitter.com/RadioSkovoroda");
}
function goToIgPage() {
window.open("https://instagram.com/radioskovoroda");
}
function goToYtPage() {
window.open("https://www.youtube.com/channel/UCSgkIdg5MztN_2z9q_8u3Nw")
}
function goToTiPage() {
window.open("http://tunein.com/radio/radio-skovoroda-s248591/")
}
// Event handler for SystemMediaTransportControls' buttonpressed event
function systemMediaControlsButtonPressed() {
if (Windows.Media.MediaControl.isPlaying === true) {
pauseMedia();
} else {
playMedia();
}
}
app.start();
})();

pjax/ajax and browser back button issues

I use pjax to ajaxify my menu links. This works fine until I use the browser back button. In my javascript file I use Common Script files (to load all the necessary js files when the user hits the url) and Script files with respect to each menu links (when navigated through pjax)
function myFunction(){
/*All the script files */
}
$(document).ready(function(){
myFunction();
/*pjax menu loading block*/
$(document).on('click', 'a[data-pjax]', function(event) {
$.pjax.click(event, '#pjax-container');
$(document).on('pjax:end', function() {
myFunction();
});
});
});
Now when I navigate to a menu item and try to come back by clicking the browser back button, the script files are getting duplicated (eg: slider images getting duplicated and table sorting not working).How to overcome this issue?

You can implement the url specific loading this way, create a queue of functions which you want to load and unload on pjax complete
The solution is based on js prototyping
// create queue for load and unload
var onLoad = new PjaxExecQueue();
var onUnload = new PjaxExecQueue();
// way to add functions to queue to run on pjax load
onLoad.queue(function() {
someFunction();
});
// way to add functions to queue to unload on pjax load
onUnload.queue(function() {
someOtherFunction();
});
// load function if url contain particular path name
onLoad.queue_for_url(function_name, 'url_section');
// check for url specific function
var URLPjaxQueueElement = function(exec_function, url) {
this.method = exec_function;
if(url) {
this.url = new RegExp(url);
} else {
this.url = /.*/;
}
};
// create a queue object
var PjaxExecQueue = function () {
this.url_exec_queue = [];
this.id_exec_queue = [];
this.fired = false;
this.indicating_loading = false;
this.content = $('#content');
};
PjaxExecQueue.prototype = {
queue: function (exec_function) {
this.url_exec_queue.unshift(new URLPjaxQueueElement(exec_function));
},
queue_for_url: function (exec_function, url_pattern) {
this.url_exec_queue.unshift(new URLPjaxQueueElement(exec_function, url_pattern));
},
queue_if_id_present: function(exec_function, id) {
this.id_exec_queue.unshift(new IDPjaxQueueElement(exec_function, id));
},
fire: function () {
if(this.indicating_loading) {
this.content.removeClass("indicate-loading");
this.indicating_loading = false;
}
if(!this.fired) {
var match_loc = window.location.pathname;
var i = this.url_exec_queue.length;
while(i--) {
this.url_exec_queue[i].fire(match_loc);
}
i = this.id_exec_queue.length;
while(i--) {
this.id_exec_queue[i].fire(match_loc);
}
}
this.fired = true;
},
reset: function() {
this.fired = false;
},
loading: function () {
this.content.addClass("indicate-loading");
this.indicating_loading = true;
this.reset();
},
count: function () {
return exec_queue.length;
},
show: function (for_url) {
for (var i=0; i < exec_queue.length; i++) {
if(for_url) {
if(exec_queue[i].url.test(for_url)) {
console.log("" + exec_queue[i].method);
}
} else{
console.log(exec_queue[i].url + " : " + exec_queue[i].method);
}
}
}
};
// before send
$(document).on('pjax:beforeSend', function() {
onLoad.loading();
onUnload.fire();
});
// after pjax complete
$(document).on('pjax:complete', function() {
onLoad.fire();
onUnload.reset();
});