When the user clicks a button an interval will start counting but the problem is that if the user clicks the button two times there will be two intervals I tried clearInterval(interval);
before assigning the interval but the timer stopped counting.
function times(){
var element=document.getElementById("sec");
counter=0;
let interval= setInterval(myFunction, 1000);
function myFunction(){
counter++;
element.innerHTML=counter;
}
}
document.querySelector('#sec').addEventListener('click', function() {
times();
})
let interval;
let counter = 0;
function times() {
clearInterval(interval);
interval = setInterval(myFunction, 1000);
counter = 0;
}
function myFunction() {
var element = document.getElementById("sec");
counter++;
element.innerHTML = counter;
console.log(counter);
}
<button id="sec">timer</button>
if to want to clear the previously set interval when ever the user clicks, Just store the interval ID in a higher scope and clear the interval the previously set interval before creating a new one.
let interval
function times(){
clearInterval(interval);
var element=document.getElementById("sec");
counter=0;
interval = setInterval(myFunction, 1000);
function myFunction(){
counter++;
element.innerHTML=counter;
}
}
You may try the following. Depending on the existence of the interval it is decided whether to (re-)start the timer or stop it.
let interval
function times(){
var element=document.getElementById("sec");
counter=0;
if (interval) {
clearInterval(interval)
interval = null
} else {
function myFunction(){
counter++;
element.innerHTML=counter;
}
element.innerHTML=counter; // just to show '0' when re-starting
interval= setInterval(myFunction, 1000);
}
}
<button onclick="times()">Start / Stop</button>
<span id="sec">0</span>
I have developed a login page. I am saving sessionId in local storage on login and I want to clear it after some time. But that to be if someone(logged-user) not active for some time. If he is active, I don't want to clear. But I did that even he is active also, I am clearing the local storage. Please help to know how to catch he is active or not.
localStorage.setItem('userId', data.id);
localStorage.setItem('user', data.phone);
localStorage.setItem('sessionId', (Math.random()*1e64).toString(36));
var interval = setInterval(function(){
console.log('In localStorage');
localStorage.removeItem('sessionId');
clearInterval(interval);
alert('Session expired!!')
}, (30*60*1000));
You can just check use a setInterval:
var idleTime = 0;
$(document).ready(function () {
//Increment the idle time counter every minute.
var idleInterval = setInterval(timerIncrement, 60000); // 1 minute
//Zero the idle timer on mouse movement.
$(this).mousemove(function (e) {
idleTime = 0;
});
$(this).keypress(function (e) {
idleTime = 0;
});
});
function timerIncrement() {
idleTime = idleTime + 1;
if (idleTime > 19) { // 20 minutes
localStorage.removeItem('sessionId');
}
}
Answer borrowed from here
var sec = 10
var timer = setInterval(function() {
$('#timer span').text(sec--);
if (sec == -1) {
clearInterval(timer);
} }, 1000);
html
<div id="timer"><span>10</span> seconds</div>
Recount
What I want to do when I click recount is to recount back to 10 seconds the timer?
How can I possibly done it?
It is better to use setInterval() or setTimeout()?
Factor out your code into functions so you can call the same code on startup or when the link is clicked. You can see it working here: http://jsfiddle.net/jfriend00/x3S7j/. This even allows you to click the link during the countdown and it will start over.
$("#recount").click(function() {
initCounter(10);
});
var remainingTime;
var runningInterval = null;
function initCounter(duration) {
function stopCounter() {
if (runningInterval) {
clearInterval(runningInterval);
runningInterval = null;
}
}
stopCounter(); // stop previously running timer
remainingTime = duration; // init duration
$('#timer span').text(remainingTime); // set initial time remaining
runningInterval = setInterval(function() { // start new interval
$('#timer span').text(remainingTime--);
if (remainingTime < 0) {
stopCounter();
}
}, 1000);
}
initCounter(10);
You can just add a click handler and factor out your code in a separate method:
var sec = 10;
var timer;
function startCountdown() {
if (timer) clearInterval(timer);
sec = 10;
timer = setInterval(function() {
$('#timer span').text(sec--);
if (sec == -1) {
clearInterval(timer);
}
}, 1000);
}
$(function() {
startCountdown();
$("#recount").click(startCountdown);
});
Working JSFiddle
When you click recount, you should
sec = 10;
clearInterval(timer);
timer = setInterval(that_function, 1000);
Also, there's a difference between setInterval and setTimeout. setInterval schedules the function to be called every some milliseconds. setTimeout schedules the function to be called once, after some milliseconds.
I have written a javascript function that uses setInterval to manipulate a string every tenth of a second for a certain number of iterations.
function timer() {
var section = document.getElementById('txt').value;
var len = section.length;
var rands = new Array();
for (i=0; i<len; i++) {
rands.push(Math.floor(Math.random()*len));
};
var counter = 0
var interval = setInterval(function() {
var letters = section.split('');
for (j=0; j < len; j++) {
if (counter < rands[j]) {
letters[j] = Math.floor(Math.random()*9);
};
};
document.getElementById('txt').value = letters.join('');
counter++
if (counter > rands.max()) {
clearInterval(interval);
}
}, 100);
};
Instead of having the interval set at a specific number, I would like to update it every time it runs, based on a counter. So instead of:
var interval = setInterval(function() { ... }, 100);
It would be something like:
var interval = setInterval(function() { ... }, 10*counter);
Unfortunately, that did not work. It seemed like "10*counter" equals 0.
So, how can I adjust the interval every time the anonymous function runs?
You could use an anonymous function:
var counter = 10;
var myFunction = function(){
clearInterval(interval);
counter *= 10;
interval = setInterval(myFunction, counter);
}
var interval = setInterval(myFunction, counter);
UPDATE: As suggested by A. Wolff, use setTimeout to avoid the need for clearInterval.
var counter = 10;
var myFunction = function() {
counter *= 10;
setTimeout(myFunction, counter);
}
setTimeout(myFunction, counter);
Use setTimeout() instead. The callback would then be responsible for firing the next timeout, at which point you can increase or otherwise manipulate the timing.
EDIT
Here's a generic function you can use to apply a "decelerating" timeout for ANY function call.
function setDeceleratingTimeout(callback, factor, times)
{
var internalCallback = function(tick, counter) {
return function() {
if (--tick >= 0) {
window.setTimeout(internalCallback, ++counter * factor);
callback();
}
}
}(times, 0);
window.setTimeout(internalCallback, factor);
};
// console.log() requires firebug
setDeceleratingTimeout(function(){ console.log('hi'); }, 10, 10);
setDeceleratingTimeout(function(){ console.log('bye'); }, 100, 10);
I like this question - inspired a little timer object in me:
window.setVariableInterval = function(callbackFunc, timing) {
var variableInterval = {
interval: timing,
callback: callbackFunc,
stopped: false,
runLoop: function() {
if (variableInterval.stopped) return;
var result = variableInterval.callback.call(variableInterval);
if (typeof result == 'number')
{
if (result === 0) return;
variableInterval.interval = result;
}
variableInterval.loop();
},
stop: function() {
this.stopped = true;
window.clearTimeout(this.timeout);
},
start: function() {
this.stopped = false;
return this.loop();
},
loop: function() {
this.timeout = window.setTimeout(this.runLoop, this.interval);
return this;
}
};
return variableInterval.start();
};
Example use
var vi = setVariableInterval(function() {
// this is the variableInterval - so we can change/get the interval here:
var interval = this.interval;
// print it for the hell of it
console.log(interval);
// we can stop ourselves.
if (interval>4000) this.stop();
// we could return a new interval after doing something
return interval + 100;
}, 100);
// we can change the interval down here too
setTimeout(function() {
vi.interval = 3500;
}, 1000);
// or tell it to start back up in a minute
setTimeout(function() {
vi.interval = 100;
vi.start();
}, 60000);
I had the same question as the original poster, did this as a solution. Not sure how efficient this is ....
let interval = 5000; // initial condition
let run = setInterval(request, interval); // start setInterval as "run"
function request() {
console.log(interval); // firebug or chrome log
clearInterval(run); // stop the setInterval()
// dynamically change the run interval
if (interval > 200) {
interval = interval * .8;
} else {
interval = interval * 1.2;
}
run = setInterval(request, interval); // start the setInterval()
}
This is my way of doing this, i use setTimeout:
var timer = {
running: false,
iv: 5000,
timeout: false,
cb : function(){},
start : function(cb,iv){
var elm = this;
clearInterval(this.timeout);
this.running = true;
if(cb) this.cb = cb;
if(iv) this.iv = iv;
this.timeout = setTimeout(function(){elm.execute(elm)}, this.iv);
},
execute : function(e){
if(!e.running) return false;
e.cb();
e.start();
},
stop : function(){
this.running = false;
},
set_interval : function(iv){
clearInterval(this.timeout);
this.start(false, iv);
}
};
Usage:
timer.start(function(){
console.debug('go');
}, 2000);
timer.set_interval(500);
timer.stop();
A much simpler way would be to have an if statement in the refreshed function and a control to execute your command at regular time intervals . In the following example, I run an alert every 2 seconds and the interval (intrv) can be changed dynamically...
var i=1;
var intrv=2; // << control this variable
var refreshId = setInterval(function() {
if(!(i%intrv)) {
alert('run!');
}
i++;
}, 1000);
This can be initiated however you want. timeout is the method i used to keep it on the top of the hour.
I had the need for every hour to begin a code block on the hour. So this would start at server startup and run the interval hourly. Basicaly the initial run is to begin the interval within the same minute. So in a second from init, run immediately then on every 5 seconds.
var interval = 1000;
var timing =function(){
var timer = setInterval(function(){
console.log(interval);
if(interval == 1000){ /*interval you dont want anymore or increment/decrement */
interval = 3600000; /* Increment you do want for timer */
clearInterval(timer);
timing();
}
},interval);
}
timing();
Alternately if you wanted to just have something happen at start and then forever at a specific interval you could just call it at the same time as the setInterval. For example:
var this = function(){
//do
}
setInterval(function(){
this()
},3600000)
this()
Here we have this run the first time and then every hour.
I couldn't synchronize and change the speed my setIntervals too and I was about to post a question. But I think I've found a way. It should certainly be improved because I'm a beginner. So, I'd gladly read your comments/remarks about this.
<body onload="foo()">
<div id="count1">0</div>
<div id="count2">2nd counter is stopped</div>
<button onclick="speed0()">pause</button>
<button onclick="speedx(1)">normal speed</button>
<button onclick="speedx(2)">speed x2</button>
<button onclick="speedx(4)">speed x4</button>
<button onclick="startTimer2()">Start second timer</button>
</body>
<script>
var count1 = 0,
count2 = 0,
greenlight = new Boolean(0), //blocks 2nd counter
speed = 1000, //1second
countingSpeed;
function foo(){
countingSpeed = setInterval(function(){
counter1();
counter2();
},speed);
}
function counter1(){
count1++;
document.getElementById("count1").innerHTML=count1;
}
function counter2(){
if (greenlight != false) {
count2++;
document.getElementById("count2").innerHTML=count2;
}
}
function startTimer2(){
//while the button hasn't been clicked, greenlight boolean is false
//thus, the 2nd timer is blocked
greenlight = true;
counter2();
//counter2() is greenlighted
}
//these functions modify the speed of the counters
function speed0(){
clearInterval(countingSpeed);
}
function speedx(a){
clearInterval(countingSpeed);
speed=1000/a;
foo();
}
</script>
If you want the counters to begin to increase once the page is loaded, put counter1() and counter2() in foo() before countingSpeed is called. Otherwise, it takes speed milliseconds before execution.
EDIT : Shorter answer.
(function variableInterval() {
//whatever needs to be done
interval *= 2; //deal with your interval
setTimeout(variableInterval, interval);
//whatever needs to be done
})();
can't get any shorter
Here is yet another way to create a decelerating/accelerating interval timer. The interval gets multiplied by a factor until a total time is exceeded.
function setChangingInterval(callback, startInterval, factor, totalTime) {
let remainingTime = totalTime;
let interval = startInterval;
const internalTimer = () => {
remainingTime -= interval ;
interval *= factor;
if (remainingTime >= 0) {
setTimeout(internalTimer, interval);
callback();
}
};
internalTimer();
}
Make new function:
// set Time interval
$("3000,18000").Multitimeout();
jQuery.fn.extend({
Multitimeout: function () {
var res = this.selector.split(",");
$.each(res, function (index, val) { setTimeout(function () {
//...Call function
temp();
}, val); });
return true;
}
});
function temp()
{
alert();
}
This piece of code below accelerates (acceleration > 1) or decelerates (acceleration <1) a setInterval function :
function accelerate(yourfunction, timer, refresh, acceleration) {
var new_timer = timer / acceleration;
var refresh_init = refresh;//save this user defined value
if (refresh < new_timer ){//avoid reseting the interval before it has produced anything.
refresh = new_timer + 1 ;
};
var lastInter = setInterval(yourfunction, new_timer);
console.log("timer:", new_timer);
function stopLastInter() {
clearInterval(lastInter);
accelerate(yourfunction, new_timer, refresh_init, acceleration);
console.log("refresh:", refresh);
};
setTimeout(stopLastInter, refresh);
}
With :
timer: the setInterval initial value in ms (increasing or decreasing)
refresh: the time before a new value of timer is calculated. This is the step lenght
acceleration: the gap between the old and the next timer value. This is the step height
Inspired by the internal callback above, i made a function to fire a callback at fractions of minutes. If timeout is set to intervals like 6 000, 15 000, 30 000, 60 000 it will continuously adapt the intervals in sync to the exact transition to the next minute of your system clock.
//Interval timer to trigger on even minute intervals
function setIntervalSynced(callback, intervalMs) {
//Calculate time to next modulus timer event
var betterInterval = function () {
var d = new Date();
var millis = (d.getMinutes() * 60 + d.getSeconds()) * 1000 + d.getMilliseconds();
return intervalMs - millis % intervalMs;
};
//Internal callback
var internalCallback = function () {
return function () {
setTimeout(internalCallback, betterInterval());
callback();
}
}();
//Initial call to start internal callback
setTimeout(internalCallback, betterInterval());
};
This is my idea for times when you do not want loops like setInterval to overlap.
You also want to be able to set the loop execution delay and start and stop the loop, instansly on the fly.
I am using a loop_flag variable and a setTimeout function.
I set the main function to async so that you can call other functions in the body by calling await. When the main body of your code is running, the main loop waits and does not repeat itself. (which is not the case with setInterval)
An example of a simple code is:
//#NabiKAZ
document.getElementById("btn_start").addEventListener("click", function() {
console.log("Starting...");
loop_flag = true;
loop_func();
});
document.getElementById("btn_stop").addEventListener("click", function() {
console.log("Stoping...");
loop_flag = false;
});
var n = 0;
var loop_flag = false;
var loop_func = async function() {
if (!loop_flag) {
console.log("STOP.");
return;
}
//body main function inhere
n++;
console.log(n);
////
if (loop_flag) {
setTimeout(loop_func, document.getElementById("inp_delay").value);
} else {
console.log("STOP.");
}
}
<input id="inp_delay" value="1000">
<button id="btn_start">START</button>
<button id="btn_stop">STOP</button>
For a more complete code with a fetch request inside the loop, see here:
https://jsfiddle.net/NabiKAZ/a5hdw2bo/
You can use a variable and change the variable instead.
setInterval(() => function, variable)
You can do this by clearing the interval every iteration, changing the timer value and setting the interval again. Hope it helps ;)
For exemple:
const DOMCounter = document.querySelector(".counter")
let timer = 1000
const changeCounter = () => {
clearInterval(interval)
DOMCounter.innerHTML = timer
timer += 1000
timer == 5000 && timer == 1000
interval = setInterval(changeCounter, timer)
}
let interval = setInterval(changeCounter, timer)
<div class="container">
<p class="counter"></p>
</div>
var counter = 15;
var interval = function() {
setTimeout(function(){
// Write your code here and remove console.log, remember that you need declare yourDynamicValue and give it a value
console.log((new Date()).getTime())
window.counter = yourDynamicValue;
window.interval();
}, counter);
}
// It needs to run just once as init
interval();