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How to create a timer per question using JavaScript

I will like to achieve something in a quiz system.
Right about now I have a quiz system that works perfectly well. It closes the quiz after 10:00 min is elapsed.
But what I want now is, for each of the question there should be a timer.
So Question 1 would have 10 secs, Question 2 would also have 10 secs down to Question 20.
So when you fail to answer any question within ten seconds, it automatically takes you to the next question.
Right about now, what happens is that you must click on the next question button before it takes you to the next question, which is what I want to change.
Below is the code that does the timer and submit after 10 min
<script>
//function that keeps the counter going
function timer(secs){
var ele = document.getElementById("countdown");
ele.innerHTML = "Your Time Starts Now";
var mins_rem = parseInt(secs/60);
var secs_rem = secs%60;
if(mins_rem<10 && secs_rem>=10)
ele.innerHTML = " "+"0"+mins_rem+":"+secs_rem;
else if(secs_rem<10 && mins_rem>=10)
ele.innerHTML = " "+mins_rem+":0"+secs_rem;
else if(secs_rem<10 && mins_rem<10)
ele.innerHTML = " "+"0"+mins_rem+":0"+secs_rem;
else
ele.innerHTML = " "+mins_rem+":"+secs_rem;
if(mins_rem=="00" && secs_rem < 1){
quiz_submit();
}
secs--;
//to animate the timer otherwise it'd just stay at the number entered
//calling timer() again after 1 sec
var time_again = setTimeout('timer('+secs+')',1000);
}
</script>
<script>
setTimeout(function() {
$("form").submit();
}, 600000);
</script>
Here is the code that does the onclick to next question
<script type="text/javascript">
$('.cont').addClass('hide');
count=$('.questions').length;
$('#question'+1).removeClass('hide');
$(document).on('click','.next',function(){
last= parseInt($(this).attr('id'));
nex = last+1;
$('#question'+last).addClass('hide');
$('#question'+nex).removeClass('hide');
});
$(document).on('click','.previous',function(){
last = parseInt($(this).attr('id'));
pre = last-1;
$('#question'+last).addClass('hide');
$('#question'+pre).removeClass('hide');
});
setTimeout(function() {
$("form").submit();
}, 120000);
</script>
Please note that I fetch my questions with Php Mysqli

Initialize a timeout into a variable at start. The callback should simulate a click on the next button. Use .click() to simulate. It will execute all click event listeners associated to the button.
You also have to reset the timer when button is clicked (manually or not).
EDIT: After discussing by comments, I guess that you have <button.next> tags for each question in your HTML, with a numeric ID. So I propose you to stock in a variable your current progression.
// Initializes
let currentQuestion = 1;
let question_timer = setTimeout(question_timeout_callback, 10000);
// Function which simulates the click.
function question_timeout_callback() {
// Simulates
$(document).find(`#${currentQuestion}`).click();
}
// your code...
// And in your click event listener:
$(document).on('click','.next', function () {
// Resets timer
clearTimeout(question_timer);
question_timer = setTimeout(question_timeout_callback, 10000);
// Update question tracking
currentQuestion++;
// your code...
});
// Do NOT forget to update .previous buttons with "currentQuestion--"
Now, do not forget to ask yourself how you will handle the possibility to come back to the previous question.

i would suggest different approach.
first, take the time-counting to the backend of your application (so user can't tamper with it).
when user begins quiz, save start time and user identifier into db.
implement timeout (2s interval?) to ask backend, how much time is left.
create simple script which loads remaining time from db (calculates how much time remains for current question) and returns it to the frontend.
php:
<?php
$user = (int) $_GET['user'];
$questionNumber = (int) $_GET['question'];
//connect to the db
//select eg. with PDO
$st = $db->prepare('SELECT start_time FROM quiz_completion WHERE user_id = :user');
$st->bindParam(':user', $user, PDO::PARAM_INT);
$startTimeRow = $sth->execute();
//calculate remaining time
$elapsed = time() - $startTimeRow['start_time'];
$borderTime = 10 * $questionNumber;
echo $borderTime - $elapsed;
exit(0);
with mocked GET & db: https://3v4l.org/MId0K
then in js just call this script with user identifier and question number. when less than zero is returned, move user to the next question.
js:
$.ajax('http://localhost/your_php_script.php?user='+user+'&question='+questionNumber).done(
function(response){
if (response < 0) {
//move to the next q.
} else {
//show remaining time?
}
});
with asking backend to get time, there is risk of waiting too long for an answer from php (when many users are completing the poll)

How do I dynamically change the background.js to reflect a user's setting in chrome?

So I am developing a chrome extension right now in order to get introduced to the world of web development. I have run into a issue which I can't seem to get my head wrapped around. Currently, my background.js gets all the open windows along with the open tabs in each of them using:
function getAllOpenWindows(winData) {
var tabs = [];
for (var i in winData) {
/*if (winData[i].focused === true) {*/
var winTabs = winData[i].tabs;
var totTabs = winTabs.length;
for (var j=0; j<totTabs;j++) {
tabs.push(winTabs[j].url);
}
/*}*/
}
console.log(tabs);
}
which was actually posted by bpatel here. Now as you can see the commented line, it allows me to decide if the tabs are taken from just the current focused window or all the windows. My issue is that how exactly can I change this setting dynamically once the extension has been loaded into chrome and is being used actively? So if a user goes into options and says they want only all the windows I would be able pass a message to my background.js to say "hey use the all windows function and not the current focused window". I understand that 2 seperate functions should ideally be used here, this is just a sample on how it would be done. Thanks a ton!

You can use localstorage to save any user settings.
The options page and the background page share the same localstorage, so you can update the setting from options page and access the value from background page.
options.html
<input type="checkbox" id="windowType" value="All">Check all windows</input>
<input type="button" id="saveSettings" value="Save">Save</input>
options.js
document.getElementById("saveSettings").onclick = save_settings;
function save_settings()
{
var checkAll = document.getElementById("windowType").checked;
localStorage.setItem("check_all_windows",checkAll);
}
You can use a similar function to update the value of the checkbox with the current value, when the options page loads.
background.js
function getAllOpenWindows(winData) {
var tabs = [];
for (var i in winData) {
var checkAll = (localStorage.getItem("check_all_windows") == "true");
if (checkAll || winData[i].focused === true) {
var winTabs = winData[i].tabs;
var totTabs = winTabs.length;
for (var j=0; j<totTabs;j++) {
tabs.push(winTabs[j].url);
}
}
}
console.log(tabs);
}
In background.js, you can get the value of the same key from localStorage and check if it is set to true or false. Remember that the localStorage will store values as strings so you need to compare it with the proper strings - if("false") will evaluate to true.

Greasemonkey popup loop not waiting for load-event listener

I'm writing a Greasemonkey script to automatically delete my notifications from a site, based on words I enter into a search box.
The delete "button" is basically a link, so I'm trying to open the first link in a new tab. Then, after it loads enough, open the rest of the links, one by one, in that same tab.
I figured out how to get the links I needed and how to loop and manipulate them. I was able to grab the first delete-link and open it in a new tab. I added an event listener to make sure the page was loaded before going to the next link.
I finally made that work so added my search box and button. Then I had to figure out how to wrap the whole thing in the event listener again.
So, I now have the whole thing working, except only the last link loads.
All links are going to my waitFor function so they should open, so it seems the event listener isn't working so it goes through the loop too fast and only the last link loads.
How do I make this script not continue the loop until the previous loaded page is fully loaded?
Complete code except for box and button creation:
var mytable = document.getElementById ('content').getElementsByTagName ('table')[0]
var myrows = mytable.rows
//function openLinkInTab () {
//mywin2.close ();
//}
var mywin2;
mywin2 = window.open ("http://www.aywas.com/message/notices/test/", "my_win2");
var links;
var waitFor = function (i) {
links = myrows[i].cells[1].getElementsByTagName ("a");
mywin2 = window.open (links[0].href, "my_win2");
}
var delnotifs = function () {
var matching;
var toRemove;
toRemove = document.getElementById ('find').value;
alert (toRemove)
for (i = 0; i < 10; i++) {
matching = myrows[i].cells[0].innerHTML;
if (matching.indexOf (toRemove) > 0) {
mywin2.addEventListener ('load', waitFor (i), false);
}
}
}
searchButton.addEventListener ('click', delnotifs, true);
So, why isn't it waiting for `mywin2.addEventListener('load', waitFor(i), false);`? I have a feeling it's something extremely simple that I'm missing here, but I just can't see it.
I also tried mywin2.addEventListener('load', function(){waitFor(i)}, false); and it still does the same thing, so it's not a problem of being a call instead of a pointer.
Swapping mywin2.addEventListener('load', waitFor(i), false); for
if (mywin2.document.readyState === "complete") { waitFor(i)} doesn't work either.
And while I'm at it... every time I see code looping through a list like this it uses
for(i=1;i < myrows.length;i++)
Which was skipping the first link in the list since arrays start at zero. So my question is, if I switch 'i' to zero, and the loop only goes while 'i' is < length, doesn't that mean it won't go through the whole list? Shouldn't it be
for(i=0;i != myrows.length;i++)

When you open a popup (or tab) with window.open, the load event only fires once -- even if you "open" a new URL with the same window handle.
To get the load listener to fire every time, you must close the window after each URL, and open a new one for the next URL.
Because popups are asynchronous and you want to load these links sequentially, don't use a for() loop for that. Use the popup load status to "chain" the links.
Here is the code to do that. It pushes the links onto an array, and then uses the load event to grab and open the next link. You can see the code in action at jsFiddle. :
var searchButton = document.getElementById ('gmPopUpBtn');
var mytable = document.getElementById ('content').getElementsByTagName ('table')[0];
var myrows = mytable.rows;
var linksToOpen = [];
var mywin2 = null;
function delnotifs () {
var toRemove = document.getElementById ('find').value;
for (var J = 0, L = myrows.length; J < L; J++) {
var matching = myrows[J].cells[0].innerHTML;
if (matching.indexOf (toRemove) > 0) {
var links = myrows[J].cells[1].getElementsByTagName ("a");
linksToOpen.push (links[0].href); //-- Add URL to list
}
}
openLinksInSequence ();
};
function openLinksInSequence () {
if (mywin2) {
mywin2.close ();
mywin2 = null;
}
if (linksToOpen.length) {
var link = linksToOpen.shift ();
mywin2 = window.open (link, "my_win2");
mywin2.addEventListener ('load', openLinksInSequence, false);
}
}
searchButton.addEventListener ('click', delnotifs, true);

See https://developer.mozilla.org/en-US/docs/Web/API/EventTarget.addEventListener.
The second argument of the addEventLister function must be a pointer to a function and not a call.

Same function repeatedly called resets the setTimeout inner function

All,
I have a 'credit module' (similar to credit system in games), which when a user performs an action, creates an inner div with the cost to be added or substracted so user can see what the cost of the last action was.
Problem: Everything works fine as long as the function is called once, if the user performs multiple actions quickly, the setTimeout functions (which are suppose to animate & then delete the cost div) donot get executed. It seems the second instance of the function resets the setTimeout function of the first.
(function()
{
$("#press").on("click", function(){creditCost(50)});
function creditCost(x)
{
var eParent = document.getElementById("creditModule");
// following code creates the div with the cost
eParent.innerHTML += '<div class="cCCost"><p class="cCostNo"></p></div>';
var aCostNo = document.getElementsByClassName("cCostNo");
var eLatestCost = aCostNo[aCostNo.length - 1];
// following line assigns variable to above created div '.cCCost'
var eCCost = eLatestCost.parentNode;
// cost being assigned
eLatestCost.innerHTML = x;
$(eCCost).animate ({"left":"-=50px", "opacity":"1"}, 250, "swing");
// following code needs review... not executing if action is performed multiple times quickly
setTimeout(function()
{
$(eCCost).animate ({"left":"+=50px", "opacity":"0"}, 250, "swing", function ()
{
$(eCCost).remove();
})
}, 1000);
}
})();
jsfiddle, excuse the CSS

eParent.innerHTML += '<div class="cCCost"><p class="cCostNo"></p></div>';
is the bad line. This resets the innerHTML of your element, recreating the whole DOM and destroying the elements which were referenced in the previous invocations - letting their timeouts fail. See "innerHTML += ..." vs "appendChild(txtNode)" for details. Why don't you use jQuery when you have it available?
function creditCost(x) {
var eParent = $("#creditModule");
// Create a DOM node on the fly - without any innerHTML
var eCCost = $('<div class="cCCost"><p class="cCostNo"></p></div>');
eCCost.find("p").text(x); // don't set the HTML if you only want text
eParent.append(eCCost); // don't throw over all the other children
eCCost.animate ({"left":"-=50px", "opacity":"1"}, 250, "swing")
.delay(1000) // of course the setTimeout would have worked as well
.animate ({"left":"+=50px", "opacity":"0"}, 250, "swing", function() {
eCCost.remove();
});
}

You are starting an animation and scheduling a timeout to work on DOM elements that will get modified in the middle of that operation if the user clicks quickly. You have two options for fixing this:
Make the adding of new items upon a second click to be safe so that it doesn't mess up the previous animations.
Stop the previous animations and clean them up before starting a new one.
You can implement either behavior with the following rewrite and simplification of your code. You control whether you get behavior #1 or #2 by whether you include the first line of code or not.
function creditCost(x) {
// This first line of code is optional depending upon what you want to happen when the
// user clicks rapid fire. With this line in place, any previous animations will
// be stopped and their objects will be removed immediately
// Without this line of code, previous objects will continue to animate and will then
// clean remove themselves when the animation is done
$("#creditModule .cCCost").stop(true, false).remove();
// create HTML objects for cCCost
var cCCost = $('<div class="cCCost"><p class="cCostNo">' + x + '</p></div>');
// add these objects onto end of creditModule
$("#creditModule").append(cCCost);
cCCost
.animate ({"left":"-=50px", "opacity":"1"}, 250, "swing")
.delay(750)
.animate({"left":"+=50px", "opacity":"0"}, 250, "swing", function () {
cCCost.remove();
});
}
})();
Note, I changed from setTimeout() to .delay() to make it easier to stop all future actions. If you stayed with setTimeout(), then you would need to save the timerID returned from that so that you could call clearTimeout(). Using .delay(), jQuery does this for us.

Updated code for anyone who might want to do with mostly javascript. Jsfiddle, excuse the CSS.
function creditCost(x)
{
var eParent = document.getElementById("creditModule");
var eCCost = document.createElement("div");
var eCostNo = document.createElement("p");
var sCostNoTxt = document.createTextNode(x);
eCCost.setAttribute("class","cCCost");
eCostNo.setAttribute("class","cCostNo");
eCostNo.appendChild(sCostNoTxt);
eCCost.appendChild(eCostNo);
eParent.insertBefore(eCCost, document.getElementById("creditSystem").nextSibling);
$(eCCost).animate ({"left":"-=50px", "opacity":"1"}, 250, "swing");
setTimeout(function()
{
$(eCCost).animate ({"left":"+=50px", "opacity":"0"}, 250, "swing", function ()
{
$(eCCost).remove();
})
}, 1000);
}

display message javascript while a calculation is being made

I have been looking around and I cannot seem to figure out how to do this, although it seems like it would be very simple.(mobile development)
What I am trying to do is display a message (kind of like an alert, but not an alert, more like a dialog) while a calculation is being made. Simply like a Loading please wait. I want the message to appear and stay there while the calculation is being done and then be removed. I just cannot seem to find a proper way of doing this.
The submit button is pressed and first checks to make sure all the forms are filled out then it should show the message, it does the calculation, then hides the message.
Here is the Calculation function.
function scpdResults(form) {
//call all of the "choice" functions here
//otherwise, when the page is refreshed, the pulldown might not match the variable
//this shouldn't be a problem, but this is the defensive way to code it
choiceVoltage(form);
choiceMotorRatingVal(form);
getMotorRatingType();
getProduct();
getConnection();
getDisconnect();
getDisclaimer();
getMotorType();
//restore these fields to their default values every time submit is clicked
//this puts the results table into a known state
//it is also used in error checking in the populateResults function
document.getElementById('results').innerHTML = "Results:";
document.getElementById('fuse_cb_sel').innerHTML = "Fuse/CB 1:";
document.getElementById('fuse_cb_sel_2').innerHTML = "Fuse/CB 2:";
document.getElementById('fuse_cb_result').innerHTML = "(result1)";
document.getElementById('fuse_cb_res_2').innerHTML = "(result2)";
document.getElementById('sccr_2').innerHTML = "<b>Fault Rating:</b>";
document.getElementById('sccr_result').innerHTML = "(result)";
document.getElementById('sccr_result_2').innerHTML = "(result)";
document.getElementById('contactor_result').innerHTML = "(result)";
document.getElementById('controller_result').innerHTML = "(result)";
//Make sure something has been selected for each variable
if (product === "Choose an Option." || product === "") {
alert("You must select a value for every field. Select a Value for Product");
**************BLAH************
} else {
//valid entries, so jump to results table
document.location.href = '#results_a';
******This is where the message should start being displayed***********
document.getElementById('motor_result').innerHTML = motorRatingVal + " " + motorRatingType;
document.getElementById('voltage_res_2').innerHTML = voltage + " V";
document.getElementById('product_res_2').innerHTML = product;
document.getElementById('connection_res_2').innerHTML = connection;
document.getElementById('disconnect_res_2').innerHTML = disconnect;
if (BLAH) {
}
else {
}
populateResults();
document.getElementById('CalculatedResults').style.display = "block";
} //end massive else statement that ensures all fields have values
*****Close out of the Loading message********
} //scpd results
Thank you all for your time, it is greatly appreciated

It is a good idea to separate your display code from the calculation code. It should roughly look like this
displayDialog();
makeCalculation();
closeDialog();
If you are having trouble with any of those steps, please add it to your question.

Computers are fast. Really fast. Most modern computers can do several billion instructions per second. Therefore, I'm fairly certain you can rely on a a setTimeout function to fire around 1000ms to be sufficient to show a loading message.
if (product === "Choose an Option." || product === "") {
/* ... */
} else {
/* ... */
var loader = document.getElementById('loader');
loader.style.display = 'block';
window.setTimeout(function() {
loader.style.display = 'none';
document.getElementById('CalculatedResults').style.display = "block";
}, 1000);
}
<div id="loader" style="display: none;">Please wait while we calculate.</div>

You need to give the UI main thread a chance to render your message before starting your calculation.
This is often done like this:
showMessage();
setTimeout(function() {
doCalculation();
cleanUp()
}, 0);
Using the timer allows the code to fall through into the event loop, update the UI, and then start up the calculation.

You're already using a section to pop up a "results" page -- why not pop up a "calculating" page?
Really, there are 4,000,000 different ways of tackling this problem, but why not try writing a "displayCalculatingMessage" function and a "removeCalculatingMessage" function, if you don't want to get all object-oriented on such a simple thing.
function displayCalculatingMessage () {
var submit_button = getSubmitButton();
submit_button.disabled = true;
// optionally get all inputs and disable those, as well
// now, you can either do something like pop up another hidden div,
// that has the loading message in it...
// or you could do something like:
var loading_span = document.createElement("span");
loading_span.id = "loading-message";
loading_span.innerText = "working...";
submit_button.parentElement.replaceChild(loading_span, submit_button);
}
function removeCalculatingMessage () {
var submit_button = getSubmitButton(),
loading_span = document.getElementById("loading-message");
submit_button.disabled = false;
loading_span.parentElement.replaceChild(submit_button, loading_span);
// and then reenable any other disabled elements, et cetera.
// then bring up your results div...
// ...or bring up your results div and do this after
}
There are a billion ways of accomplishing this, it all comes down to how you want it to appear to the user -- WHAT you want to have happen.