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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);
};

Only run a JavaScript function if it is not run again after a set amount of time

I have an input which controls the state of an element changing very rapidly. This causes that element to flicker as parts of it change.
I am trying to store these state changes and then providing nothing has changed for a set amount of time (an arbitrary 500ms) change the state.
I have tried to solve this using timeouts as demonstrated in the code below (the same code as in the fiddle.):
var changingToHappy = false;
// Original no attempts to fix functions.
//var ifHappy = function () {
// $("#face").text(':)');
//};
//
//var ifNotHappy = function () {
// $("#face").text(':(');
//};
var ifHappy = function () {
changingToHappy = true;
setTimeout(function () {
if (changingToHappy) {
$("#face").text(':)');
}
}, 500);
};
var ifNotHappy = function () {
changingToHappy = false;
setTimeout(function () {
if (!changingToHappy) {
$("#face").text(':(');
}
}, 500);
};
$("#textBox").keypress(
function (event) {
if (event.which == 49) {
ifHappy();
$("#flickerFace").text(':)');
}
if (event.which == 50) {
ifNotHappy();
$("#flickerFace").text(':(');
}
}
);
If you rapidly press 1, 2, 1, 2 and so on in the fiddle the face will remain not flickery for a moment and then the timeouts will catchup and it will begin to change state.
This fiddle http://jsfiddle.net/9w70wxgz/4/ simulates the problem.
To clarify I only want the face to change if nothing has tried to change its state for a set amount of time.

What you're looking for is called a debounced function, here is an example with a piece of your code (you're almost there):
//storage for timer
var notHappyTimer;
var ifNotHappy = function () {
changingToHappy = false;
//removes timer if event fires in less than 500ms
clearTimeout(notHappyTimer);
//resets it to attempt again in 500ms
notHappyTimer = setTimeout(function () {
if (!changingToHappy) {
$("#face").text(':(');
}
}, 500);
};
As you can see, you just assign the timeout to a variable that clears itself every time the function is fired, then starts the timer again. This ensures that the text change only happens if the function hasn't been fired in 500ms.

Simulating Spinner Number with mousedown

I made a control (numeric spinner up and down), to work in a table:
JSFIDDLE: http://jsfiddle.net/Leandro1981/wn8vd/1/
and I want simulate the "mousedown, increment while mouse button is helding" but I can't do it. I tried to mix it with the following and functional script:
JSFIDDLE: http://jsfiddle.net/Leandro1981/kKW85/
but I couldn't make it.
My last attempt here:
http://jsfiddle.net/Leandro1981/S8Zt9/1/
Maybe the wrong is the
timeout = setInterval(function () {
But I couldn't figure out. I'm using bootstrap 3, so I can't use some JQuery UI plugins...
Any help will be preciated!
Please comment below if you have any question, comment or anything to improve this question, and sorry for my english :)
Please be free to use my code/control in any way.
Thanks and kind regards

Write a factory to set up each control so you get a closure over the variables, now it's just a matter of being able to make it work given the relevant elements. For this, you'll need to
Listen for mousedown on the up and down nodes to set off the changes
Start a timeout loop to keep doing your change
Listen for mouseup on window to ensure you cancel the timeout loop (you may also want to listen for mouseout/loss of focus)
So all together,
function spinFactory(node, up, down) { // I wrote this vanilla :D
var spinning, delta;
window.addEventListener('mouseup', stopSpin);
function spin() {
node.value = +node.value + delta;
spinning = setTimeout(spin, 500);
}
function stopSpin() { // maybe also invoke this on mouseout/loss of focus
window.clearTimeout(spinning);
delta = 0;
}
up.addEventListener('mousedown', function spinUp() {
delta = 1;
spin();
});
down.addEventListener('mousedown', function spinDown() {
delta = -1;
spin();
});
}
// apply to your control, used a bit of jQuery to make life easier
$('.PNET-spinner').each(function () {
spinFactory(
this.getElementsByTagName('input')[0],
$(this).find('.btn:first-of-type')[0],
$(this).find('.btn:last-of-type')[0]
);
});
DEMO

I have updated the Fiddle here ... Please check this and it might helps you..
Script
$('.PNET-spinner .btn:first-of-type').on('mousedown', function (e) {
var timer, proxy = this;
timer = setInterval(function () {
increment(proxy);
}, 200);
$(document).one("mouseup", function () {
increment(proxy);
if (timer) clearInterval(timer);
});
});
$('.PNET-spinner .btn:last-of-type').on('mousedown', function () {
var timer, proxy = this;
timer = setInterval(function () {
decrement(proxy);
}, 200);
$(document).one("mouseup", function () {
decrement(proxy);
if (timer) clearInterval(timer);
});
});
function increment(proxy) {
var numupdown = $('.PNET-spinner input', $(proxy).closest("tr"));
var inputValue = parseInt($(numupdown).val(), 10);
inputValue++;
$(numupdown).val(inputValue);
}
function decrement(proxy) {
var numupdown = $('.PNET-spinner input', $(proxy).closest("tr"));
var inputValue = parseInt($(numupdown).val(), 10);
if (inputValue > 1) {
inputValue--;
$(numupdown).val(inputValue);
}
}

You simply need to take care of two things. First, your function to increment and decrement the value in the textbox should be called again and again till user do mouseout or mouseup. Second, make surethis has the right value in var numupdown = $('.PNET-spinner input', $(this).closest("tr"));
Following code shows how to do it for the increment button. Similar thing, you can implement for decrement button.
var timeout;
var inc = function () {
var myThis = this;
var numupdown = $('.PNET-spinner input', $(this).closest("tr"));
var inputValue = parseInt($(numupdown).val(), 10);
inputValue++;
console.log(inputValue);
$(numupdown).val(inputValue);
clearTimeout(timeout);
timeout = setTimeout(function(){
//http://stackoverflow.com/questions/3630054/how-do-i-pass-the-this-context-to-a-function
inc.apply(myThis, arguments);
}, 1000);
};
var incStop = function(){
clearTimeout(timeout);
}
$('.PNET-spinner .btn:first-of-type').on('mousedown', inc);
$('.PNET-spinner .btn:first-of-type').on('mouseup', incStop);
$('.PNET-spinner .btn:first-of-type').on('mouseout', incStop);
Check this DEMO here.

JQuery not executing within a For loop

Im a JQuery noob trying to write a simple jQuery code to get a text to blink three times. My initial code was as follows:
$("#welcome").click(function () {
var i = 1;
while (++i < 10) {
$("#welcome").fadeOut("slow", function () { $("#welcome").fadeIn("slow"); })();
}
});
But since I probably meddled in forces I could not comprehend, the above code made the text blink only once. I read up on closures and got convinced that the below code could make a change. Unfortunately, it doesnt.
$("#welcome").click(function () {
var i = 1;
while (++i < 10) {
(function (i) {
$("#welcome").fadeOut("slow", function () { $("#welcome").fadeIn("slow"); })();
})(i);
}
});
Can anyone tell me whats going on here?

You need make use of the animation queue
var $welcome = $("#welcome").click(function () {
var i = 1;
//clear previous animations
$welcome.stop(true, true);
while (++i < 10) {
$welcome.fadeOut("slow").fadeIn("slow");
}
});
Demo: Fiddle

Fading in and out takes some time, and you have to wait for your animation to be over before you can run the next one.
The provided answers solve your problem since jQuery is clever enough to bufferize your animation queue, but it may creates even more confusion for begginers, and also if you want to do something else between the fading animations, you can't rely on it anymore.
You then have to write your code on what is called an asynchronous recursive way (woah). Simply trying to understand that snippet may help you a lot with javascript general programming.
function blink(nbBlinks) {
// Only blink if the nbBlinks counter is not zero
if(nbBlinks > 0) {
$('#welcome').fadeOut('slow', function() {
// Do stuff after the fade out animation
$(this).fadeIn('slow', function() {
// Now we're done with that iteration, blink again
blink(nbBlinks-1);
})
});
}
}
// Launch our blinking function 10 times
blink(10);

This works perfectly. Demo http://jsfiddle.net/X5Qy3/
$("#welcome").click(function () {
for (var x = 0; x < 3; x += 1) {
$("#welcome").fadeOut("slow");
$("#welcome").fadeIn("slow");
}
});
Also, if you know how many times you want to do something. You should use a For Loop. While Loops are for when you don't know how many times you want it to run.

Set in queue
$("#welcome").click(function () {
var i = 1;
//clear animations whcih are running at that time
$(this).stop(true, true);
while (++i < 10) {
$(this).fadeOut("slow").fadeIn("slow");
}
});

You can not use jQuery delay function inside a looping/iteration hence you have to user closures:
$(document).ready(function(){
$(".click1").click(function () {
for (i=0;i<=10;i++) {
setTimeout(function(x) {
return function() {
$("#wrapper").fadeOut("slow", function () { $("#wrapper").fadeIn("slow"); })();
};
}(i), 1000*i);
}
});
});
<div id="wrapper"></div><div class="click1">click</div>
You can later change the count how many times you want to blink the <div>.

Repeat code every x seconds but not if [insert check here]

This is a followup to this question, where I found out how to make code be repeated every x seconds. Is it possible to make an event that can change this? I.e. I have a checkbox which is meant to control whether this is repeated or not, so I figured I'd need something like this:
$(checkbox).bind("change", function() {
switch(whether if it is ticked or not) {
case [ticked]:
// Make the code repeat, while preserving the ability to stop it repeating
case [unticked]:
// Make the code stop repeating, while preserving the ability to start again
}
});
I have no idea what I could put in the cases.

You can do it by assigning your setInterval function to a variable.
var interval = setInterval(function() { }, 1000);
and then you can stop setInterval by
clearInterval(interval);
p.s.
to start your interval you need to call var interval = setInterval(function() { }, 1000); again

You can either stop and start the interval:
var timer;
function start() {
timer = window.setInterval(function(){
// do something
}, 1000);
}
function stop() {
window.clearInterval(timer);
}
start();
$(checkbox).bind("change", function() {
if ($(this).is(':checked')) {
start();
} else {
stop();
}
});
Or you can have a flag causing the interval to skip the code:
var enabled = true;
var timer = window.setInterval(function(){
if (!enabled) {
// do something
}
}, 1000);
$(checkbox).bind("change", function() {
enabled = $(this).is(':checked');
});

function fooFunc() {
$('#foo').text(+new Date());
}
var id;
var shouldBeStopped = false;
$('input').change(function() {
if (shouldBeStopped)
clearInterval(id);
else
id = setInterval(fooFunc, 200);
shouldBeStopped = !shouldBeStopped;
});​
Live DEMO