Develop Reference

Calling setInterval from within function

I'm making a slider and i ran into problem. I'm practicing modular js and this code works fine for the first time, but setInterval won't repeat itself so the slides continue changing. How to make it work? Thanks in advance.
var currentSlide = 1;
var slider = {
init: function(){
this.cacheDom();
this.setInt();
},
cacheDom: function(){
this.$panel = $('.slider');
this.$actPan = this.$panel.find('.panel.active');
},
setInt: function(){
return setInterval(this.mainFunction(), 3000);
},
mainFunction: function(){
this.$actPan.fadeOut(2000, this.showNextPanel());
this.$panel.find('.tabs li:nth-child('+ currentSlide +')').find('img').attr('src', 'images/g4228.png');
},
showNextPanel: function(){
this.$panel.find('#panel' + currentSlide).removeClass('active');
this.revert();
},
revert: function(){
currentSlide++;
if(currentSlide === 4){currentSlide = 1;}
this.$panel.find('.tabs li:nth-child('+ currentSlide +')').find('img').attr('src', 'images/g4228.png');
this.$panel.find('#panel' + currentSlide).fadeIn(2000, this.adder());
},
adder: function(){
this.$panel.find('#panel' + currentSlide).addClass('active');
}
};
slider.init();
So, I'm thinking that only setInt and init functions needs changing.

The problem is this line:
return setInterval(this.mainFunction(), 3000);
This is calling this.mainFunction() and passing the result to setInterval; setInterval needs to be passed a function to call on an interval. Replace that with this:
return setInterval(this.mainFunction.bind(this), 3000);
The bind is needed so that this is preserved when setInterval calls it.

How can I depend on the interval that I just cleared in jquery?

It's a follow up to this question - https://stackoverflow.com/a/33430608/3766930
Basically I have a text area and when user starts typing in sth, the counter starts going down from 3 to 0. when it reaches 0 it gets disabled.
Now I want to add a feature of starting over - when user clicks the link start over, text area goes enabled again and user has 3 seconds (again) to perform the input.
I modified the jquery script:
$('#textArea').on('input propertychange', display30Seconds);
var interval;
function display30Seconds() {
var validTime = 3000;
if (!interval)
interval = setInterval(function () {
$('#counter').html(validTime / 1000);
validTime = validTime - 1000;
if (validTime < 0) {
clearInterval(interval);
alert('Time Up!');
$('#textArea').prop('disabled', true);
$('#counter').html('start over');
$('#counterIsDone').on('click', function(){
$('#textArea').prop('disabled', false);
display30Seconds();
});
}
}, 1000);
}
but I see that I cannot call the method display30Seconds(); again. Or rather I can, but the interval is not set again. How can I fix it?
Seems like I'm not entering the code inside
if (!interval)
because the interval is not visible any more after clearing it (?). So I thought about moving the var interval; into the body of the method function display30Seconds() {, but that doesn't bring the expected effect. Is there a way of fixing it?
Here is my updated fiddle: http://jsfiddle.net/jf4ea4nx/3/

Set interval=null after the clearInterval() call.
What seems to confuse you is the semantics of clearInterval(interval). As Patrick Evans points out in his comment, it will not set interval to a value that evaluates to false in a condition.
To make it completely clear you could use a boolean variable such as countdownRunning in addition to the interval variable to keep track of whether the countdown is active or not.

Try this:
$('#textArea').on('input propertychange', display30Seconds);
var interval=false;
function display30Seconds() {
var validTime = 3000;
if (!interval)
interval = setInterval(function () {
$('#counter').html(validTime / 1000);
validTime = validTime - 1000;
if (validTime < 0) {
clearInterval(interval);
alert('Time Up!');
$('#textArea').prop('disabled', true);
$('#counter').html('start over');
$(document).on('click','#counterIsDone', function(){
$('#textArea').prop('disabled', false);
display30Seconds();
});
interval=false;
}
}, 1000);
}

You can improve your code by using a conditional recursive call to to your iterative function instead - each call has a one second delay, which makes it slightly more intuitive to use (think of each call as one tick):
var seconds = 3;
$('#textArea').on('input propertychange', setTimeout(timeout.bind(null, seconds), 1000));
function timeout (iterations) {
$('#counter').html(iterations);
if (iterations === 0) {
alert('Time Up!');
$('#textArea').prop('disabled', true);
$('#counter').html('start over');
$('#counterIsDone').on('click', function(){
$('#textArea').prop('disabled', false);
timeout(seconds);
});
}
else {
setTimeout(timeout.bind(null, --iterations), 1000);
}
}
The bind function simply binds the arguments of the bind function to the arguments of the timeout call - the first argument to the bind function declares its this scope; but don't worry about that too much.
You can modify the duration of the timer by changing the seconds var. Hope this helps :)

Stopping increment at specific height

I am animating images within a logo in a slot-machine type of animation. I need it to stop animating once it gets to the top of the image (and send a callback if possible).
Currently, this is how I'm accomplishing the animation:
window.setInterval(function() {
$('#title-1 img').animate({bottom : '-=60px'})
}, 5000);
Any ideas on how I would get it to stop, and to send the callback?

So I assume you have a sprite image containing multiple logos, you want them to slide each 5 seconds until you reach the last one, and then call the callback?
var cnt = 6,
$img = $('#title-1 img'),
i = 0;
function animate_logo(cb) {
if (i < cnt) {
$('#title-1 img').animate({bottom : '-=60px'});
i += 1;
setTimeout(function () {animate_logo(cb)}, 5000);
}
else {
cb();
}
}();

var interval = window.setInterval(function() {
$('#title-1 img').animate({bottom : '-=60px'},
function(){
if(`some stop point`) clearInterval(interval);
}
);
}, 5000);

I would not suggest using a setInterval when dealing with animations due to the way newer browsers are making changes to the way setInterval and setTimeout work when the tab is not the active tab.
var $title1 = $("#title-1");
var $title1img = $title1.find('img');
function anim(){
if ($title1.height() < parseInt($title1img.css("bottom"))) {
setTimeout(function(){
$title1img.animate({bottom : '-=60px'},anim);
},5000);
}
}
$title1img.animate({bottom : '-=60px'},anim);
Edit: another reason not to use setInterval to fire off animations is due to the reqeustAnimationFrame that was implemented in 1.6 and removed in 1.6.3, which will more than likely be added back in 1.7. If you write code now that will be compatible later, that's less maintenance you will have to do later if you end up being required to upgrade.
Here's a jsfiddle http://jsfiddle.net/czUnU/
Edit: function...
function animColumn(title,img){
function anim(){
if (title.height() < parseInt(img.css("bottom")) {
setTimeout(function(){
img.animate({bottom : '-=60px'},anim);
},5000);
}
}
img.animate({bottom : '-=60px'},anim);
}
animColumn($("#title-1"),$("#title-1 img"));
animColumn($("#title-2"),$("#title-2 img"));
animColumn($("#title-3"),$("#title-3 img"));
http://jsfiddle.net/czUnU/1/

setTimeout / clearTimeout problems

I try to make a page to go to the startpage after eg. 10sec of inactivity (user not clicking anywhere). I use jQuery for the rest but the set/clear in my test function are pure javascript.
In my frustation I ended up with something like this function that I hoped I could call on any click on the page. The timer starts fine, but is not reset on a click. If the function is called 5 times within the first 10 seconds, then 5 alerts will apear... no clearTimeout...
function endAndStartTimer() {
window.clearTimeout(timer);
var timer;
//var millisecBeforeRedirect = 10000;
timer = window.setTimeout(function(){alert('Hello!');},10000);
}
Any one got some lines of code that will do the trick?
- on any click stop, reset and start the timer.
- When timer hits eg. 10sec do something.

You need to declare timer outside the function. Otherwise, you get a brand new variable on each function invocation.
var timer;
function endAndStartTimer() {
window.clearTimeout(timer);
//var millisecBeforeRedirect = 10000;
timer = window.setTimeout(function(){alert('Hello!');},10000);
}

The problem is that the timer variable is local, and its value is lost after each function call.
You need to persist it, you can put it outside the function, or if you don't want to expose the variable as global, you can store it in a closure, e.g.:
var endAndStartTimer = (function () {
var timer; // variable persisted here
return function () {
window.clearTimeout(timer);
//var millisecBeforeRedirect = 10000;
timer = window.setTimeout(function(){alert('Hello!');},10000);
};
})();

That's because timer is a local variable to your function.
Try creating it outside of the function.

A way to use this in react:
class Timeout extends Component {
constructor(props){
super(props)
this.state = {
timeout: null
}
}
userTimeout(){
const { timeout } = this.state;
clearTimeout(timeout);
this.setState({
timeout: setTimeout(() => {this.callAPI()}, 250)
})
}
}
Helpful if you'd like to only call an API after the user has stopped typing for instance. The userTimeout function could be bound via onKeyUp to an input.

Not sure if this violates some good practice coding rule but I usually come out with this one:
if(typeof __t == 'undefined')
__t = 0;
clearTimeout(__t);
__t = setTimeout(callback, 1000);
This prevent the need to declare the timer out of the function.
EDIT: this also don't declare a new variable at each invocation, but always recycle the same.
Hope this helps.

Practical example Using Jquery for a dropdown menu !
On mouse over on #IconLoggedinUxExternal shows div#ExternalMenuLogin and set time out to hide the div#ExternalMenuLogin
On mouse over on div#ExternalMenuLogin it cancels the timeout.
On mouse out on div#ExternalMenuLogin it sets the timeout.
The point here is always to invoke clearTimeout before set the timeout, as so, avoiding double calls
var ExternalMenuLoginTO;
$('#IconLoggedinUxExternal').on('mouseover mouseenter', function () {
clearTimeout( ExternalMenuLoginTO )
$("#ExternalMenuLogin").show()
});
$('#IconLoggedinUxExternal').on('mouseleave mouseout', function () {
clearTimeout( ExternalMenuLoginTO )
ExternalMenuLoginTO = setTimeout(
function () {
$("#ExternalMenuLogin").hide()
}
,1000
);
$("#ExternalMenuLogin").show()
});
$('#ExternalMenuLogin').on('mouseover mouseenter', function () {
clearTimeout( ExternalMenuLoginTO )
});
$('#ExternalMenuLogin').on('mouseleave mouseout', function () {
clearTimeout( ExternalMenuLoginTO )
ExternalMenuLoginTO = setTimeout(
function () {
$("#ExternalMenuLogin").hide()
}
,500
);
});

This works well. It's a manager I've made to handle hold events. Has events for hold, and for when you let go.
function onUserHold(element, func, hold, clearfunc) {
//var holdTime = 0;
var holdTimeout;
element.addEventListener('mousedown', function(e) {
holdTimeout = setTimeout(function() {
func();
clearTimeout(holdTimeout);
holdTime = 0;
}, hold);
//alert('UU');
});
element.addEventListener('mouseup', clearTime);
element.addEventListener('mouseout', clearTime);
function clearTime() {
clearTimeout(holdTimeout);
holdTime = 0;
if(clearfunc) {
clearfunc();
}
}
}
The element parameter is the one which you hold. The func parameter fires when it holds for a number of milliseconds specified by the parameter hold. The clearfunc param is optional and if it is given, it will get fired if the user lets go or leaves the element. You can also do some work-arounds to get the features you want. Enjoy! :)

<!DOCTYPE html>
<html>
<body>
<h2>EJEMPLO CONOMETRO CANCELABLE</h2>
<button onclick="inicioStart()">INICIO</button>
<input type="text" id="demostracion">
<button onclick="finStop()">FIN</button>
<script>
let cuenta = 0;
let temporalTiempo;
let statusTime = false;
function cronometro() {
document.getElementById("demostracion").value = cuenta;
cuenta++;
temporalTiempo = setTimeout(cronometro, 500);
}
function inicioStart() {
if (!Boolean(statusTime)) {
statusTime = true;
cronometro();
}
}
function finStop() {
clearTimeout(temporalTiempo);
statusTime = false;
}
</script>
</body>
</html>

Resetting a setTimeout

I have the following:
window.setTimeout(function() {
window.location.href = 'file.php';
}, 115000);
How can I, via a .click function, reset the counter midway through the countdown?

You can store a reference to that timeout, and then call clearTimeout on that reference.
// in the example above, assign the result
var timeoutHandle = window.setTimeout(...);
// in your click function, call clearTimeout
window.clearTimeout(timeoutHandle);
// then call setTimeout again to reset the timer
timeoutHandle = window.setTimeout(...);

clearTimeout() and feed the reference of the setTimeout, which will be a number. Then re-invoke it:
var initial;
function invocation() {
alert('invoked')
initial = window.setTimeout(
function() {
document.body.style.backgroundColor = 'black'
}, 5000);
}
invocation();
document.body.onclick = function() {
alert('stopped')
clearTimeout( initial )
// re-invoke invocation()
}
In this example, if you don't click on the body element in 5 seconds the background color will be black.
Reference:
https://developer.mozilla.org/en/DOM/window.clearTimeout
https://developer.mozilla.org/En/Window.setTimeout
Note: setTimeout and clearTimeout are not ECMAScript native methods, but Javascript methods of the global window namespace.

You will have to remember the timeout "Timer", cancel it, then restart it:
g_timer = null;
$(document).ready(function() {
startTimer();
});
function startTimer() {
g_timer = window.setTimeout(function() {
window.location.href = 'file.php';
}, 115000);
}
function onClick() {
clearTimeout(g_timer);
startTimer();
}

var myTimer = setTimeout(..., 115000);
something.click(function () {
clearTimeout(myTimer);
myTimer = setTimeout(..., 115000);
});
Something along those lines!

For NodeJS it's super simple:
const timeout = setTimeout(...);
timeout.refresh();
From the docs:
timeout.refresh()
Sets the timer's start time to the current time, and reschedules the timer to call its callback at the previously specified duration adjusted to the current time. This is useful for refreshing a timer without allocating a new JavaScript object.
But it won't work in JavaScript because in browser setTimeout() returns a number, not an object.

This timer will fire a "Hello" alertbox after 30 seconds. However, everytime you click the reset timer button it clears the timerHandle then re-sets it again. Once it's fired, the game ends.
<script type="text/javascript">
var timerHandle = setTimeout("alert('Hello')",3000);
function resetTimer() {
window.clearTimeout(timerHandle);
timerHandle = setTimeout("alert('Hello')",3000);
}
</script>
<body>
<button onclick="resetTimer()">Reset Timer</button>
</body>

var redirectionDelay;
function startRedirectionDelay(){
redirectionDelay = setTimeout(redirect, 115000);
}
function resetRedirectionDelay(){
clearTimeout(redirectionDelay);
}
function redirect(){
location.href = 'file.php';
}
// in your click >> fire those
resetRedirectionDelay();
startRedirectionDelay();
here is an elaborated example for what's really going on http://jsfiddle.net/ppjrnd2L/

i know this is an old thread but i came up with this today
var timer = []; //creates a empty array called timer to store timer instances
var afterTimer = function(timerName, interval, callback){
window.clearTimeout(timer[timerName]); //clear the named timer if exists
timer[timerName] = window.setTimeout(function(){ //creates a new named timer
callback(); //executes your callback code after timer finished
},interval); //sets the timer timer
}
and you invoke using
afterTimer('<timername>string', <interval in milliseconds>int, function(){
your code here
});

$(function() {
(function(){
var pthis = this;
this.mseg = 115000;
this.href = 'file.php'
this.setTimer = function() {
return (window.setTimeout( function() {window.location.href = this.href;}, this.mseg));
};
this.timer = pthis.setTimer();
this.clear = function(ref) { clearTimeout(ref.timer); ref.setTimer(); };
$(window.document).click( function(){pthis.clear.apply(pthis, [pthis])} );
})();
});

To reset the timer, you would need to set and clear out the timer variable
$time_out_handle = 0;
window.clearTimeout($time_out_handle);
$time_out_handle = window.setTimeout( function(){---}, 60000 );