js setTimeout() finishes instantly without any rest - javascript

when coding, I came upon this very weird problem. My code is below:
js
document.getElementById("id").style.width = "0%"
var a = 0;
setTimeout(function () {
if (a <= 60) {
document.getElementById("id").style.width = a + "%";
a++;
}
}, 100);
I want it to run 60 times, each time changing the div's width by 1%
However, when I run the code, the if block makes it finish instantly as if the timeout didn't work. Can anyone tell me what's wrong? Thanks in advance!

setTimeout function executes only once after that specified time in milli seconds.
If you want to keep on executing the block, you have to make use of setInterval instead of setTimeout.
setInterval keeps on calling the function since the interval is cleared.
Dont forget to call clearInterval once target achieved.
var a = 0;
const interval = setInterval(function () {
if (a <= 60) {
console.log("Im being called");
document.getElementById("id").style.width = a + "%";
a++;
} else {
// Target achieved, clearing interval
console.log("Im stoping execution");
clearInterval(interval)
}
}, 100);
#id {
height: 300px;
background: orange;
}
<div id="id"></div>

Related

Countdown function doesn't display last number in 3-2-1 countdown

Pretty much what the title says. When the countdown starts, it goes "3", "2", and then executes the function that's supposed to launch when the timer hits zero, skipping the display of the number "1".
The actual timer output is displayed in a separate div element, you'll see in my code below.
I've seen some answers on here about faulty countdown clocks but a lot of them use jQuery whereas I'm just using vanilla JavaScript and the use of libraries is still a bit confusing to me.
var count = 3;
function startTimer() {
var timer = setInterval(function() {startTimer(count);}, 1000);
if(count === 0){
clearInterval(timer);
ranCoord(); //function to run when timer hits zero.
} else {
document.getElementById("target").innerText = count;
count--;
}
}
<div class="start">
<img src="images/start-default.png" onclick="startTimer();" alt="Click Here"/>
</div>
<div id="target"></div>
I noticed that if I include the var count=3 variable inside the startTimer(); function, the countdown doesn't work either, it just stays at number 3. Does anyone know why this is?
Also, if I include the var timer = setInterval(function() {startTimer(count);}, 1000); outside the function then it runs automatically on page load, which is not what I want. I want the countdown to start on the click of a button, and found that this worked when placed inside the function.
Thanks in advance!
If the count variable is declared inside of the startTimer function, then each iteration of the timer will have its count value overwritten and so will not count down.
setInterval repeats its function indefinitely, so only needs to be called once outside of the loop, as opposed to setTimeout which only runs once and needs to be called each iteration.
An alternative approach using setTimeout would be:
function startTimer(count) {
if (count <= 0) {
ranCoord();
} else {
document.getElementById("target").innerText = count;
setTimeout(function() { startTimer(--count); }, 1000);
}
}
This version also avoids the use of a global variable, by passing the remaining count in as a parameter.
You dont need to call startTimer in the setInterval
var count = 3;
function startTimer() {
var timer = setInterval(function() {
if (count === 0) {
clearInterval(timer);
ranCoord(); //function to run when timer hits zero.
} else {
document.getElementById("target").innerText = count;
count--;
}
}, 1000);
}
function ranCoord() {
console.log("Timer hit 0")
}
img {
height: 100px;
width: 100px;
outline: 1px solid blue;
}
<div class="start">
<img src="images/start-default.png" onclick="startTimer();" />
</div>
<div id="target"></div>
I think you not need to add more code you just need to simplify it like that
var count = 3;
function startTimer() {
const timer = setInterval(function () {
document.getElementById("target").innerText = count;
count--;
if (count <= 0) {
clearInterval(timer);
ranCoord();
}
}, 1000)
}

javascript setTimeout not working inside if statement

I'm writing a code to alert the user inactive when the user is idle for some time.
setIdleTimeout = () => {
var timeout = 0;
timeout = setTimeout(onExpires, 500);
//Expires Function
function onExpires() {
timeout = 0;
alert('Timed out');
}
//This function executes on each mouse move.
function onMouseActivity(event) {
clearTimeout(timeout);
timeout = setTimeout(onExpires, 500);
}
}
The above code works fine. But when ever I add a condition to the clearTimeout, Its not working.
example:
//This function executes on each mouse move.
function onMouseActivity(event) {
var mouseSeconds =5
if(mouseSeconds < 10) {
//Now this is not working.
clearTimeout(timeout);
}
timeout = setTimeout(onExpires, 500);
}
Please help me out. This is driving me crazy for hours now.
Thanks.
you wrote
var mouseSeconds =5
if(mouseSeconds > 10) {
//Now this is not working.
clearTimeout(timeout);
}
mouseSeconds is 5 it will never be bigger then 10 :) so the statement is always false.

Change background images using setTimeout

I have 31 images and I want to display them one after another as the background of a div. I only want it to change when the user hovers over the div. My problem right now is that it just flips through all the images really fast. I am attempting to use setTimeout, but it isn't working. How can I make the delay work?
The name of the div is About_Me_Block and the images are called frame1.gif,frame2.gif ...etc
Here is my code:
function changeImg(counter) {
$('#About_Me_Block').attr("style", "background-image: url(playGif/frame" + counter + ".gif);");
}
$(document).ready(function() {
var hoverAnimate = []
"use strict";
$('#About_Me_Block').mouseenter(function() {
hoverAnimate[0] = true;
var counter = 0;
while (hoverAnimate[0]) {
console.log(counter);
setTimeout(changeImg(counter), 1000);
counter++;
if (counter === 32)
hoverAnimate[0] = false;
}
});
$('#About_Me_Block').mouseleave(function() {
hoverAnimate[0] = false;
$(this).attr("style", "background-image: url(play.jpeg);");
});
});
setTimeout doesn't wait for the function to end, it works lile threading in other languages.
To achieve a what you want, you need to call setTimeout from the changeImg function.
var counter = 0;
$(document).ready(function() {
var hoverAnimate = []
"use strict";
$('#About_Me_Block').mouseenter(function() {
hoverAnimate[0] = true;
counter = 0;
changeImg();
});
$('#About_Me_Block').mouseleave(function() {
hoverAnimate[0] = false;
$(this).attr("style", "background-image: url(play.jpeg);");
});
});
function changeImg() {
$('#About_Me_Block').attr("style", "background-image: url(playGif/frame" + counter + ".gif);");
counter++;
if (counter < 32 && hoverAnimate[0]) {
setTimeout(changeImg, 1000);
} else {
hoverAnimate[0] = false;
}
}
the reason they happen all at once is because while statement doesn't have delay, so all setTimeout will be set up at the same time, thus, calling changeImg all at once.
To solve this problem, you can replace setTimeout with setInterval. Instead of using while, you can just call setInterval like
var counter = 0;
var myTimer = setInterval(changeImg, 1000);
and update counter inside changeImg every time it gets called. After looping, don't forget to
clearInterval(myTimer)
It seems you need to read up on how setTimeout works. It essentially places a reminder to run a function after a given amount of milliseconds have passed. So, when you do setTimeout(changImg(counter), 1000) you are calling changImg(counter) which returns undefined. Therein producing this setTimeout(undefined, 1000) which is why it flips really fast.
So, you can use bind to allow the function to be called later with that parameter built in. Also, make sure you remove the reminders once done with clearTimeout.
function changeImg(counter) {
$('#About_Me_Block').attr("style", "background-image: url(playGif/frame" + counter + ".gif);");
}
$(document).ready(function() {
var hoverAnimate = false, id;
function loop(counter) {
if(hoverAnimate || counter < 32) {
changeImg(counter);
id = setTimeout(loop.bind(this, counter++), 1000);
}
}
$('#About_Me_Block').mouseenter(function() {
hoverAnimate = true;
id = setTimeout(loop.bind(this, 0), 1000);
});
$('#About_Me_Block').mouseleave(function() {
hoverAnimate = false;
// Don't want a reminder for a random counter to wake up.
clearTimeout(id);
$(this).attr("style", "background-image: url(play.jpeg);");
});
});
Two methods for timers - setTimeout and SetInterval (single / repeating)
// setInterval is also in milliseconds
var intervalHandle = setInterval(<yourFuncToChangeImage>,5000);
//this handle loop and make example loop stop
yourelement.yourEvent = function() {
clearInterval(intervalHandle);
};

How to change the interval dynamically when using setInterval

I have this fiddle : https://jsfiddle.net/reko91/stfnzoo4/
Im currently using Javascripts setInterval() to log a string to console.
What I want to do, is in this setInterval function check whether the interval variable has changed, if it has, change the interval in the setInterval function. I can lower the interval variable by 100 (speeding the function up) by a click a button.
Is this possible ?
Someone mentioned this : Changing the interval of SetInterval while it's running
But this is using a counter, so they only run it a certain amount of times. I need to run it for however long, but change how fast the function gets called again.
Here is the code :
var interval = 2000;
setInterval(function() {
interval = getInterval();
console.log('interval')
}, interval);
function getInterval() {
return interval;
}
$('#speedUp').on('click', function() {
interval -= 100;
console.log(interval)
})
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<button id='speedUp'>
speed up
</button>
I would just stop the interval and start a new one with the different timing
var interval = 2000;
var intervalId;
// store in a function so we can call it again
function startInterval(_interval) {
// Store the id of the interval so we can clear it later
intervalId = setInterval(function() {
console.log(_interval);
}, _interval);
}
function getInterval() {
return interval;
}
$('#speedUp').on('click', function() {
interval -= 100;
// clear the existing interval
clearInterval(intervalId);
// just start a new one
startInterval(interval);
console.log(interval)
})
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<button id='speedUp'>
speed up
</button>

Jquery setTimeout inside a setTimeinterval not working

I have a setinterval that moves bulldozer from the right to the left.
In the jsfiddle below, the setInterval must stop itself after 5 seconds. (used a settimeout and clearinterval for that) but it's not working. Can anyone help me?
http://jsfiddle.net/B5MKj/11/
var gameover;
gameover = setInterval(function () {
setTimeout(function () {
clearInterval(movingbulldozer);
}, 55000);
}, 10);
You had a typo in your fiddle, updated fiddle, if works just fine, but instead of 5000 ms you had 55000ms set for the timeout.
setTimeout(function () {
clearInterval(movingbulldozer);
}, 5000);
In your example, movingbulldozer is undefined. If you're trying to clear the interval, clear the interval with the right reference. In your example, this would be clearInterval(gameover);
The problem with your example is that every 10 ms you're adding a timeout to the DOM which clears the interval.
var timeout, interval, date,
i = 0;
$(document).ready(function() {
interval = setInterval(function() {
date = new Date();
i++;
$('#debug').html('Interval parsed at '+date.getTime()+', interval #'+i);
if (i >= 100) { // According to your example
$('#debug').html('Starting timeout...');
timeout = setTimeout(function() {
$('#debug').html('Timed out');
}, 5000);
clearInterval(interval);
}
}, 10);
});
Check out my example, see if it helps. :)
http://jsfiddle.net/faqq5/

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