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How do I hide a div or image after 20 seconds of flashing in Javascript?

I am busy making a memory game, where an image is to be displayed to the user, and after some 10 seconds of the image flashing, it should hide and four options are to be shown for the user to choose either the correct or incorrect answer.
So far, all I have accomplished is to load the images and cycle through all the puzzles that my code can find.
What I'm trying to do now is to make the image flash and hide after some time, while also just refreshing that section of the page, and not the entire page.
I am using C# and a user control on my page.
What I have tried so far is only
<script>
var x;
function BlinkImage() {
x = 1;
setInterval(change, 2000);
}
function change() {
if (x === 1) {
var image = document.getElementById('<%=imgMain.ClientID %>');
image.visible = false;
x = 2;
}
else {
var image = document.getElementById('<%=imgMain.ClientID %>');
image.visible = true;
x = 1;
}
}
</script>
And on loading my puzzle for that instance (in code behind)
Page.ClientScript.RegisterStartupScript(typeof(game), "Start", "<script language=javascript> BlinkImage(); </script>");
Which does fire, as I can step through the code in debugging on Firefox. But my image does not flash or blink. I understand I am just using visiblity as my "blinker". I don't know what else to use exactly.
What can I do to make the image flash or blink for, say 20 seconds, then hide the image after that time has passed? Then repeat the process once the user has made a choice.

You can try the following (comments in code):
var blinkInterval = setInterval(change, 2000), // set the interval into a variable
image = document.getElementById('test'), // replace test with your client id: <%=imgMain.ClientID %>
x = 1;
function change() {
if (x % 2 === 1) { // see if it is odd or even by modding by 2 and getting remainder
image.style.display = 'none';
} else {
image.style.display = 'block';
}
x++; // increment x
if (x === 10) { // should have happened 10 times (which is 20 seconds with your intervals being at 2 seconds)
clearInterval(blinkInterval); // clear the interval (should end hidden as odd is display none and we clear beforethe 20th is run)
}
}
<div id="test">test</div>
After the code has finished, wherever the user is making their selection, you just need to reset the blinkInterval variable:
blinkInterval = setInterval(change, 2000); // notice no need for the var declaration when you reset this

Use style attribute and change if visible/hidden
function change() {
var image = document.getElementById('<%=imgMain.ClientID %>');
//check if visible
if (image.style.visibility=="visible") {
image.style.visibility="hidden";
}
else {
image.style.visibility="visible";
}
}
;

Try this:
function flashAndHide(img_id){
var img = $("#"+img_id);
var x = 0;
var inter = setInterval(function(){
if(x % 2 == 0){
img.hide();
}else{
img.show();
}
x += 1;
}
},1000);
if(x === 20){
img.hide();
clearInterval(inter);
}
}
Haven't tested this, but it should work,

Difficulty with setInterval loop using class of Divs

$(document).ready(function fadeIt() {
$("#cool_content > div").hide();
var sizeLoop = $("#cool_content > div").length;
var startLoop = 0;
$("#cool_content > div").first().eq(startLoop).fadeIn(500);
setInterval(function () {
$("#cool_content > div").eq(startLoop).fadeOut(1000);
if (startLoop == sizeLoop) {
startLoop = 0
} else {
startLoop++;
}
$("#cool_content > div").eq(startLoop).fadeIn(1500);
}, 2000);
});
Here I want a class of divs to animate, infinitely!
However, because the interval is set to two seconds there is period where no div is showing!
What would be an appropriate way to loop the animation of these divs?
I thought about using a for loop but couldn't figure out how to pass a class of divs as arguments. All your help is appreciated.
Thanks!

Ok, generally, you should know that Javascript is a single threaded environment. Along with this, the timer events are generally not on time accurately. I'm not sure how jQuery is doing fadeIn and fadeOut, but if it's not using CSS3 transitions, it's going to be using timeOut and Intervals. So basically, there's a lot of timer's going on.
If you go with the for loop on this one, you'd be blocking the single thread, so that's not the way to go forward. You'd have to do the fade in/out by yourself in the setInterval.
Setting the opacity on each interval call. Like div.css('opacity', (opacity -= 10) + '%')
If you're trying to fade in and out sequentially, I think maybe this code would help
var opacity = 100,
isFadingIn = false;
window.setInterval(function() {
if (isFadingIn) {
opacity += 10;
if (opacity === 100) isFadingIn = false;
} else {
opacity -= 10;
if (opacity === 0) isFadingIn = true;
}
$('#coolContent > div').css('opacity', opacity + '%');
}, 2000);

Consider the following JavaScript / jQuery:
$(function(){
var divs = $('#cool_content > div').hide();
var curDiv;
var counter = 0;
var doUpdate = function(){
// Hide any old div
if (curDiv)
curDiv.fadeOut(1000);
// Show the new div
curDiv = divs.eq(counter);
curDiv.fadeIn(1000);
// Increment the counter
counter = ++counter % divs.length;
};
doUpdate();
setInterval(doUpdate, 2000);
});
This loops infinitely through the divs. It's also more efficient than your code because it only queries the DOM for the list of divs once.
Update: Forked fiddle

instead of
if (startLoop == sizeLoop)
{
startLoop = 0
}
else
{
startLoop++;
}
use
startLoop =(startLoop+1)%sizeLoop;
Check the demo http://jsfiddle.net/JvdU9/ - 1st div is being animated just immediately after 4th disappears.
UPD:
Not sure I've undestood your question, but I'll try to answer :)
It doesn't matter how many divs you are being looped - 4, 5 or 10, since number of frames are being calculated automatically
x=(x+1)%n means that x will never be greater than n-1: x>=0 and x<n.
x=(x+1)%n is just shorten equivalent for
if(x<n-1)
x++;
else
x=0;
as for me first variant is much readable:)
And sorry, I gave you last time wrong demo. Correct one - http://jsfiddle.net/JvdU9/2/

SetInterval can't see functions in Firefox

I'm pretty new to JavaScript, so please forgive me if this is a stupid question. I am using the below code to get an image to slide onto the screen and 2 more images to appear one after the other. This works fine for Chrome and IE 7-9. Unfortunately, on Firefox I get an error saying:
move is not defined [ mover = setInterval(move, 1000); ]
My Code:
//define variables
var mover = 0
var bubble1move = 0
var bubble2move = 0
if(mover != 0)
{//interval is finished
function move ()
{
console.log("moving")
clearInterval(mover)
var moving_img = document.getElementById("i_sliding_image")
var left = 0
function frame()
{
left -= 2 // update parameters
moving_img.style.left = left + 'px'// show frame
if (left == -274) // check finish condition
{
clearInterval(id)
bubble1move = setInterval(function() {bubble1()}, 2000);
}
}
var id = setInterval(frame, 10) // draw every 10ms
}
}
if(bubble1move != 0)
{//interval is finished
function bubble1()
{
clearInterval(bubble1move);
document.getElementById("img-bubble1").style.zIndex = "1";
bubble2move = setInterval(function() {bubble2()}, 2000);
}
}
if(bubble2move != 0)
{//interval is finished
function bubble2()
{
clearInterval(bubble2move)
var vBubble2 = document.getElementById("img-bubble2").style
vBubble2.zIndex = "1";
}
}
window.onload = function initialiser()
{
mover = setInterval(move, 1000);//initial time to animation
}
All getElementByIds are getting div tags containing the images.
Thanks for your time.

Looks like you are initializing your mover variable at the begining of your js to 0 and your if statement is only declaring the function if mover != 0. Initialize mover = 1; or take your function outside of the if statement(recommended). You're just trying to call move() before it exists

Move your function outside of the if. There is no reason for it to be within the if. It doesn't work on Firefox because of the way Firefox interprets functions (differently to other browsers).
See this question for more info.
Thanks to #freakish for the link.

Function not stopping when calling another one

I`m having a troubble with a simple thing.
I have an div, when clicked, an amination start (an infinite loop of images changing, simulating an animated gif).
But, when i click on the other div, the first one need to stop, and start just the other animation, and this goes on to every animation (will be 8 on total).
Here is the code for just one image loop:
var t1;
var t2;
var anim1 = new Array ('img/testes2/anim1_1.png','img/testes2/anim1_2.png');
var anim2 = new Array ('img/testes2/anim2_1.png','img/testes2/anim2_2.png');
var index = 1;
var verifica1 = 0;
var verifica2 = 0;
function rotateImage1(){
$('#imagemPrinc').fadeOut(0, function(){
$(this).attr('src', anim1[index]);
$(this).fadeIn(0, function(){
if (index == anim1.length-1){
index = 0;
}
else{
index++;
}
});
});
return false;
}
function stopTimer1(){
if(verifica1 = 1){
clearInterval(t2);
}
}
function muda1(){
if (verifica1 = 1){
//stopTimer2();
//$('#bgImagem').css({'background-image':'url(img/testes2/anim1_1.png)'});
t1 = setInterval(rotateImage1,500);
}
}
The same function for the second animation.
The verifica var, and the stopTimer function, i tried to make one stop, and just the other plays, but doesn't seems to be working. That's why it's commented on the code.
It will be easier to look the code running, so thats it ---HERE---
The clickable divs are those two Red Squares.
Someone can help me please!?
Thanks!

clearTimeout takes as argument the timer id returned by the setInterval function (here it's t1).
Instead of using fadeOut and fadeIn with a duration of 0, you should simply use hide and show.
As an aside, you can simplify this block :
if (index == anim1.length-1){
index = 0;
}
else{
index++;
}
in
index = [(index+1)%anim1.length];
And this is very wrong :
if(verifica1 = 1){
This is not a test : it always change verifica1 and is always true. You probably want ==.
Is there a point in your code where you (voluntarily) set verifica1 ?

How to create a rotating thumbnails functionality in jQuery?

Basically I need the thumbnails to rotate every time the user hovers over an image. Here is my failed attempt:
<script type="text/javascript" src="https://ajax.googleapis.com/ajax/libs/jquery/1.6.1/jquery.min.js"></script>
<script type="text/javascript">
$(function() {
$('img').hover(function() {
theImage = $(this).attr('id');
otherImages = $(this).attr('class').split('#');
rotateThumbs(otherImages, theImage);
}, function() {
//
});
});
function rotateThumbs(otherImages, theImage) {
for (i=0; i < otherImages.length; i++) {
setInterval($('#'+theImage).attr('src', otherImages[i]), 1000);
}
}
</script>
<img id="myImage" src="http://www.google.com/images/logos/ps_logo2.png" class="http://www.google.com/images/logos/ps_logo2.png#http://l.yimg.com/a/i/ww/met/yahoo_logo_us_061509.png#http://dogandcat.com/images/cat2.jpg" width="174" height="130" />
Does anyone know how this may be accomplished?

Some issues here.
setInterval requires a function reference as it's first argument, but you are executing code that returns a jQuery object.
setInterval executes the first function repeatedly at the specified interval. Is that what you are trying to do? Swap images every second?
Depending on how you correct the first issue, you could run into an issue where i is otherImages.length and thus the src is set to undefined.
Assuming you worked around issue 3, you will have the problem that the image swaps will happen imperceptibly fast and it will appear as though the last image is always displayed.
Instead, don't use a loop. Increment a counter each time a new image is displayed. Try this:
function rotateThumbs(otherImages, theImage) {
var i = 0;
var interval = setInterval(function() {
$('#'+theImage).attr('src', otherImages[i++]);
if (i >= otherImages.length) {
clearInterval(interval);
}
}, 1000);
}

I've implemented a fully-functional example here. This addresses some of the issues that #gilly3 notes, but uses closures instead of an incrementing counter to keep track of the current image:
$(function() {
$('img').hover(function() {
// declaring these variables here will preserve
// the references in the function called by setInterval
var $img = $(this),
imageList = $img.attr('class').split('#'),
intervalId;
// start the cycle
intervalId = window.setInterval(function() {
var next = imageList.pop();
if (next) {
$img.attr('src', next);
} else {
// stop the cycle
intervalId = window.clearInterval(intervalId);
}
}, 1000);
}, function() {});
});
As you can see, using a closure is much easier when you declare the function passed to setInterval inline, rather than as a separate, named function. You could still have a rotateThumbs function if you wanted, but you might need to do some more work to ensure that the variables were being passed properly.
Edit: I made an updated version that continues to cycle as long as the mouse is hovering.

I have adjusted the answer for Sam, taking pre-loading the image into account, so that you won't have a possible deplay at the first rotation.
function rotateThumbs(otherImages, theImage) {
if(!$('#'+theImage).data('setup')){
$('#'+theImage).data('setup', true); // do not double pre-loading images
var $body = $('body');
for(var j = 0; j < otherImages.length; j++){
$body.append($('<img/>').attr('src', otherImages[j])
.css('display', 'none'));
}
}
var i= 0;
setInterval(function(){
$('#'+theImage).attr('src', otherImages[i++]);
if(i >= otherImages.length){i = 0}
}, 1000);
}