Develop Reference

JS - Reset timer when click

I have a 5 minutes countdown. This function launch automatically when page load. I want to reload data of page and resetting this countdown. The code looks like this.
HTML
<a onClick="timer()" title="Pincha para actualizar" class="pull-right" id="time"></a>
JS
function timer(){
var timer = 60 * 5, minutes, seconds;
setInterval(function () {
minutes = parseInt(timer / 60, 10)
seconds = parseInt(timer % 60, 10);
minutes = minutes < 10 ? "0" + minutes : minutes;
seconds = seconds < 10 ? "0" + seconds : seconds;
$('#time').text("Tiempo restante para actualización de datos " + minutes + ":" + seconds);
if (--timer < 0) {
timer = duration;
}
}, 1000);
}
The problem: When i click the link the timer goes crazy, doesn´t reset properly.
Anybody knows what´s the rigth way to reset countdown?

You are missing a clearInterval otherwise you are creating a new interval each time you click on the element.
let interval = null;
function timer(){
var timer = 60 * 5, minutes, seconds;
if (interval !== null) {
clearInterval(interval);
}
interval = setInterval(function () {
minutes = parseInt(timer / 60, 10)
seconds = parseInt(timer % 60, 10);
minutes = minutes < 10 ? "0" + minutes : minutes;
seconds = seconds < 10 ? "0" + seconds : seconds;
$('#time').text("Tiempo restante para actualización de datos " + minutes + ":" + seconds);
if (--timer < 0) {
timer = duration;
}
}, 1000);
}

you can use clearInterval inside setInterval itself
function timer(){
var timer = 60 * 5, minutes, seconds;
interval = setInterval(()=> {
minutes = parseInt(timer / 60, 10)
seconds = parseInt(timer % 60, 10);
minutes = minutes < 10 ? "0" + minutes : minutes;
seconds = seconds < 10 ? "0" + seconds : seconds;
$('#time').text("Tiempo restante para actualización de datos " + minutes + ":" + seconds);
if (--timer < 0) {
timer = duration;
}
if (interval !== null) clearInterval(interval);
}, 1000);
}

Javascript start countdown and at the end call ajax

I am trying to start the Javascript countdown using following Javascript code. Here it's counting from 5 - 0.
Now I want when It's 0 then I will call an Ajax request (I know how to do it). But for now, I set it alert message that your session ends.
It continuously showing me the alert message But it's should be once!
Here is the JS code:
function startTimer(duration, display) {
var timer = duration, minutes, seconds;
setInterval(function () {
minutes = parseInt(timer / 60, 10)
seconds = parseInt(timer % 60, 10);
minutes = minutes < 10 ? "0" + minutes : minutes;
seconds = seconds < 10 ? "0" + seconds : seconds;
display.textContent = minutes + ":" + seconds;
if(timer !== 0 ) {
--timer;
} else if( timer == 0 ) {
alert('Your time has been completed.');
}
}, 1000);
}
window.onload = function () {
var seconds = 5,
display = document.querySelector('#time');
startTimer(seconds, display);
};

You need to assign the interval to a variable, so that you can then clear the interval after the final alert so that it doesn't run anymore:
function startTimer(duration, display) {
let timer = duration;
const interval = setInterval(function() {
let minutes = parseInt(timer / 60, 10)
let seconds = parseInt(timer % 60, 10);
minutes = minutes < 10 ? "0" + minutes : minutes;
seconds = seconds < 10 ? "0" + seconds : seconds;
display.textContent = minutes + ":" + seconds;
if (timer !== 0) {
--timer;
} else if (timer == 0) {
alert('Your time has been completed.');
clearInterval(interval);
}
}, 1000);
}
window.onload = function() {
var seconds = 5,
display = document.querySelector('#time');
startTimer(seconds, display);
};
<div id="time"></div>

you need to make use of clearInterval() method as below
var myVar = setInterval(function(){ myTimer() }, 1000);
myTimer() {
if(conditionMet)
clearInterval(myVar);
}
or just for info you can make use of interval of react js
import { interval } from 'rxjs/observable/interval';
//emit value in sequence every 1 second
const source = interval(1000);
//output: 0,1,2,3,4,5....
const subscribe = source.subscribe(val => {
if(conditionmet)
source.unsubscribe();
console.log(val);
});

ES5
function startTimer(duration, display) {
var timer = duration;
var interval = setInterval(function() {
var minutes = parseInt(timer / 60, 10)
var seconds = parseInt(timer % 60, 10);
minutes = minutes < 10 ? "0" + minutes : minutes;
seconds = seconds < 10 ? "0" + seconds : seconds;
display.textContent = minutes + ":" + seconds;
if (timer !== 0) {
--timer;
} else if (timer == 0) {
alert('Your time has been completed.');
clearInterval(interval);
}
}, 1000);
}
window.onload = function() {
var seconds = 5,
display = document.querySelector('#time');
startTimer(seconds, display);
};

How to animate this Simple Countdown

I have this countdown and I want to animate the numbers like when they change, the number flip or some fancy transition.
<div>Registration closes in <span id="time">05:00</span> minutes!</div>
function startTimer(duration, display) {
var timer = duration, minutes, seconds;
setInterval(function () {
minutes = parseInt(timer / 60, 10)
seconds = parseInt(timer % 60, 10);
minutes = minutes < 10 ? "0" + minutes : minutes;
seconds = seconds < 10 ? "0" + seconds : seconds;
display.textContent = minutes + ":" + seconds;
if (--timer < 0) {
timer = duration;
}
}, 1000);
}
window.onload = function () {
var fiveMinutes = 60 * 5,
display = document.querySelector('#time');
startTimer(fiveMinutes, display);
};
I'd appreciate any help, thankyou

Change to jquery
<div>Registration closes in <span id="time">05:00</span> minutes!</div>
$(window).load(function(){
duration=60*5;
setInterval(function () {
minutes = parseInt(timer / 60, 10)
seconds = parseInt(timer % 60, 10);
minutes = minutes < 10 ? "0" + minutes : minutes;
seconds = seconds < 10 ? "0" + seconds : seconds;
$('#display').animate({'opacity': 0}, 400, function(){
$(this).html(minutes + ":" + seconds).animate({'opacity': 1}, 400);
});
if (--timer < 0) {
timer = duration;
}
}, 1000);
});

countdown timer with number reduction after set point?

I've got a working countdown timer which starts at 30 minutes.
With only 3 minutes left (so after 27 minutes) I'd like the number 250 to decrease at random intervals from 3 minutes left down to the end of the countdown.
Any ideas?
https://codepen.io/anon/pen/bWoGrb
// Stopwatch
function startTimer(duration, display) {
var timer = duration, minutes, seconds;
setInterval(function () {
minutes = parseInt(timer / 60, 10)
seconds = parseInt(timer % 60, 10);
minutes = minutes < 10 ? "0" + minutes : minutes;
seconds = seconds < 10 ? "0" + seconds : seconds;
display.textContent = minutes + ":" + seconds;
if (--timer < 0) {
timer = duration;
}
}, 1000);
}
window.onload = function () {
var thirtyMinutes = 60 * 30,
display = document.querySelector('#stopwatch');
startTimer(thirtyMinutes, display);
};
<div id='stopwatch'></div>

Maybe use something like this (I hope I clearly understood the question):
Just using a if/else within the condition something to say: Go normal when more than 60*3, and when under 60*3 seconds rest, there is chance to do nothing
// Stopwatch
function startTimer(duration, display) {
var timer = duration, minutes, seconds;
setInterval(function () {
if(timer > 60*3 || Math.random() < 0.25) {
minutes = parseInt(timer / 60, 10)
seconds = parseInt(timer % 60, 10);
minutes = minutes < 10 ? "0" + minutes : minutes;
seconds = seconds < 10 ? "0" + seconds : seconds;
display.textContent = minutes + ":" + seconds;
if (--timer < 0) {
timer = duration;
}
} else {
/* do not reduce the timer to wait 1 interval more */
/* or maybe do like `timer -= Math.random()` if you want to reduce it faster */
}
}, 1000);
}
window.onload = function () {
var thirtyMinutes = 60 * /*30*/ 4, // just set to 4 to see faster
display = document.querySelector('#stopwatch');
startTimer(thirtyMinutes, display);
};
<div id='stopwatch'></div>

How to stop my javascript countdown by clicking a button?

I have a start button for my countdown, but i want it to stop when i click the stop button.
my html code:
<div>
<span id="timer">25:00</span>
</div>
Start
Stop
my js code:
$('#startTimerButton').click(function starter() {
function startTimer(duration, display) {
var timer = duration, minutes, seconds;
setInterval(function () {
minutes = parseInt(timer / 60, 10);
seconds = parseInt(timer % 60, 10);
minutes = minutes < 10 ? "0" + minutes : minutes;
seconds = seconds < 10 ? "0" + seconds : seconds;
display.text(minutes + ":" + seconds);
if (--timer < 0) {
timer = duration;
}
}, 1000);
}
jQuery(function ($) {
var fiveMinutes = 60 * 25,
display = $('#timer');
startTimer(fiveMinutes, display);
});
});

First, try to return your interval in the function:
function startTimer(duration, display) {
var timer = duration, minutes, seconds;
timeInterval = setInterval(function () {
minutes = parseInt(timer / 60, 10);
seconds = parseInt(timer % 60, 10);
minutes = minutes < 10 ? "0" + minutes : minutes;
seconds = seconds < 10 ? "0" + seconds : seconds;
display.text(minutes + ":" + seconds);
if (--timer < 0) {
timer = duration;
}
}, 1000);
return timeInterval;
}
Then, calling this function assign it to a variable so you can clear it later with:
var countTimeInterval = startTimer();
clearInterval(countTimeInterval);

connect the function with a variable like this: (Try without the 'var')
var my_timer = setInterval(function () { ...
And stop the timer with this function:
$("#stop_btn").click(function(){
clearInterval(my_timer);
});

You need to use the function clearInterval to stop the timer.
$(document).ready(function() {
var handler;
$('#stopTimerButton').click(function () {
if (handler) {
clearInterval(handler);
}
});
$('#startTimerButton').click(function starter() {
function startTimer(duration, display) {
var timer = duration, minutes, seconds;
handler = setInterval(function () {
minutes = parseInt(timer / 60, 10);
seconds = parseInt(timer % 60, 10);
minutes = minutes < 10 ? "0" + minutes : minutes;
seconds = seconds < 10 ? "0" + seconds : seconds;
display.text(minutes + ":" + seconds);
if (--timer < 0) {
timer = duration;
}
}, 1000);
}
jQuery(function ($) {
var fiveMinutes = 60 * 25,
display = $('#timer');
startTimer(fiveMinutes, display);
});
});
});

You need to clear the interval when a button is pressed. Suppose the button to stop is #stopTimerButton. Then, change your js to:
$('#startTimerButton').click(function starter() {
function startTimer(duration, display) {
var timer = duration, minutes, seconds;
interval = setInterval(function () {
minutes = parseInt(timer / 60, 10);
seconds = parseInt(timer % 60, 10);
minutes = minutes < 10 ? "0" + minutes : minutes;
seconds = seconds < 10 ? "0" + seconds : seconds;
display.text(minutes + ":" + seconds);
if (--timer < 0) {
timer = duration;
}
}, 1000);
}
jQuery(function ($) {
var fiveMinutes = 60 * 25,
display = $('#timer');
startTimer(fiveMinutes, display);
});
});
$('#stopTimerButton').click(function() {
clearInterval(interval);
});