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How to disable a jquery function from executing for a certain amount of time

I have a jQuery function that calculates the distance between two slideshows and detects to see if they have been scrolled past yet and tells it to display the first slide with important information on it.
However, it displays it once, but then the if statement loops and keeps displaying it, which would be expected.
I am wondering if there is a way to force the function to wait 25-ish seconds before it executes again? Any help would be much appreciated.
Here is the jQuery code:
$(window).scroll(function() {
$('.infoIdentifier').each(function() {
var scroll = $(window).scrollTop();
var objectpos = $(this).offset().top - 600;
var nextobject = $(this).parent().nextAll('.slideshow').children(".infoIdentifier")
if (nextobject.length === 0) {
var nextobjectpos = 10000;
} else {
var nextobjectpos = nextobject.offset().top - 600;
}
if (scroll > objectpos && scroll < nextobjectpos) {
var $this = $(this).parent('.slideshow');
var $currentSlide = $this.find('.active');
var $nextSlide = $this.children('.jumbotron').first();
$nextSlide.fadeIn(500).addClass('active');
$currentSlide.fadeOut(500).removeClass('active');
}
});
});
As for HTML, the slideshows are held in a main container, and each slide show with important information is tagged as class = 'infoIdentifier'. This part of the function does its job. The calculations are fine and the application of classes is fine, however, how do I disable the if (scroll > objectpos && scroll < nextobjectpos){ statement for x amount of seconds. Any help would be much appreciated. Thank you!

Here's one way to achieve this. I added a boolean outside of your scroll function called wait, which is set to false initially.
Then I added !wait as a condition to your if logic, which means it will only validate if wait is currently false.
Then inside that block, I set wait to true, and started a setTimeout for 25 seconds, after which wait is set back to false.
During those 25 seconds, that slideshow code will not run.
var wait = false;
$(window).scroll(function() {
$('.infoIdentifier').each(function() {
var scroll = $(window).scrollTop();
var objectpos = $(this).offset().top - 600;
var nextobject = $(this).parent().nextAll('.slideshow').children(".infoIdentifier")
if (nextobject.length === 0) {
var nextobjectpos = 10000;
} else {
var nextobjectpos = nextobject.offset().top - 600;
}
if (!wait && scroll > objectpos && scroll < nextobjectpos) {
var $this = $(this).parent('.slideshow');
var $currentSlide = $this.find('.active');
var $nextSlide = $this.children('.jumbotron').first();
$nextSlide.fadeIn(500).addClass('active');
$currentSlide.fadeOut(500).removeClass('active');
wait = true;
setTimeout(function() {
wait = false;
}, 25000);
}
});
});

jQuery nicescroll is not working with dynamic content and other JavaScript function that makes random effect

So here is the thing, I have a sidebar that has big height due the lots of navigation links. And I'm using jQuery nicescroll plugin to make it look fine. In the sidebar I also have h3 tag which makes a random effect of showing letters (see the code) every 4 seconds. So, when it's on - scroll is not working at all for these 4 seconds and you can't do any scrolling. I tried to use $("#sidebar").getNiceScroll().resize() but it doesn't work either. Is there any way to make it work?
<div id="sidebar">
<h3 id="output">Random</h3>
</div>
//Calling for nicescroll function for my sidebar
$(function(){
$("#sidebar").niceScroll({ cursorcolor:"#66aee9", cursorfixedheight: 400 });
})
//Random effect for my h3 tag
setInterval(function(){
$(document).ready(function(){
var theLetters = "abcdefghijklmnopqrstuvwxyz#%&^+=-"; //You can customize what letters it will cycle through
var ctnt = "Random"; // Your text goes here
var speed = 50; // ms per frame
var increment = 8; // frames per step. Must be >2
var clen = ctnt.length;
var si = 0;
var stri = 0;
var block = "";
var fixed = "";
//Call self x times, whole function wrapped in setTimeout
(function rustle (i) {
setTimeout(function () {
if (--i){rustle(i);}
nextFrame(i);
si = si + 1;
}, speed);
})(clen*increment+1);
function nextFrame(pos){
for (var i=0; i<clen-stri; i++) {
//Random number
var num = Math.floor(theLetters.length * Math.random());
//Get random letter
var letter = theLetters.charAt(num);
block = block + letter;
}
if (si == (increment-1)){
stri++;
}
if (si == increment){
// Add a letter;
// every speed*10 ms
fixed = fixed + ctnt.charAt(stri - 1);
si = 0;
}
$("#output").html(fixed + block);
block = "";
}
});
}, 4000);

I change to rows and check it in jsfiddle, looks like working scroll fine.
Before:
setInterval(function(){
$(document).ready(function(){
...
});
}, 4000);
After:
$(document).ready(function(){
setInterval(function(){
...
}, 4000);
});

ProcessMessages() in Javascript

I want to drop a div down to a certain height to display some additional content. For that I wrote following dropbox() function:
<script type="text/javascript">
function sleep(milliseconds) {
var start = new Date().getTime();
for (var i = 0; i < 1e7; i++) {
if ((new Date().getTime() - start) > milliseconds){
break;
}
}
}
function dropbox(element){
var obj = document.getElementById(element);
if(obj) {
var element = document.getElementById(element),
style = window.getComputedStyle(element),
height = style.getPropertyValue('height');
height = height.substring(0,2);
var i = 0;
for (i = height; i<200; i++)
{
sleep(100);
var tst = i+"px";
//alert(tst);
obj.style.height = tst;
}
//alert(i);
} else {
}
}
</script>
Now the problem I'm experiencing is, the box actually isn't visible during the roll down process but only after the loop has completed but I want it to look like the "Check Availability"-box on http://www.thedana.com/. How do I get this accomplished?
Thank you!

Here is a sample code. It may help you
<div class="right_content">
We deliver quick and easy registration.
Mysites.com is our hosting server and we've buit our website under observation of Mysite.com
</div>
<p class="flip">Know About us</p>
</div>
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.8.0/jquery.min.js">
</script>
<script type="text/javascript">
$(document).ready(function(){
$(".flip").mouseover(function(){
$(".right_content").slideToggle("slow");
});
});
</script>

You cannot use looping delays in browser javascript as it will make the browser unresponsive to both input and screen updating and waste the battery on a mobile device.
Instead, you should use setTimeout() which lets you schedule an activity for some time in the future. Good animation uses a tweening algorithm that schedules the next tick of the animation, then compares the elapsed time and calculates where the next animation step should be drawn and is continually self correcting in this way.
Also, if you do a Google search for javascript animation, you will find many helpful pieces of prewritten code for doing animation with plain javascript. In addition, all the major javascript libraries (such as jQuery or YUI) have significant animation capabilities built in and already written for you.
Here's a simple example:
function dropbox(elem, finalHt, duration) {
var start = new Date().getTime();
var tick = 20;
var startHt = parseInt(elem.style.height, 10);
var growHt = finalHt - startHt;
function next() {
var now = new Date().getTime();
var percent = (now - start) / duration;
var target = Math.round(startHt + (growHt * percent));
elem.style.height = Math.min(target, finalHt) + "px";
if (target < finalHt) {
setTimeout(next, tick);
}
}
setTimeout(next, tick);
}
function run() {
var item = document.getElementById("box");
item.style.height = "10px";
dropbox(item, 300, 2000);
}
Working example and more generalized code: http://jsfiddle.net/jfriend00/QxXMK/

Jquery slideshow starts with an image on the left of a row but I want it to start at the right end

I'm using this javascript and the slide show slides right to left with the images in this order and positon:
start postion > 1 | 2 | 3 | 4 | 5 | 6 etc etc
but I want to swap them so they run in this position
6 | 5 | 4 | 3 | 2 | 1 < start position
Kind of like reading a book back to front, but keeping it in the right order
I've been told I need to modify the lines labelled below: //MODIFY ME
I hope someone can help! Thank you
Here's my code
(function($) {
$.fn.slideshow = function(method) {
if ( this[0][method] ) {
return this[0][ method ].apply( this, Array.prototype.slice.call( arguments, 1 ));
} else if ( typeof method === 'object' || ! method ) {
return this.each(function() {
var ANIMATION_DURATION = .6; // The duration to flick the content. In seconds.
var MOVE_THRESHOLD = 10; // Since touch points can move slightly when initiating a click this is the
// amount to move before allowing the element to dispatch a click event.
var itemWidth;
var horizontalGap;
var $this = $(this);
var collection;
var viewItems = [];
var touchStartTransformX; // The start transformX when the user taps.
var touchStartX; // The start x coord when the user taps.
var interval; // Interval used for measuring the drag speed.
var wasContentDragged; // Flag for whether or not the content was dragged. Takes into account MOVE_THRESHOLD.
var targetTransformX; // The target transform X when a user flicks the content.
var touchDragCoords = []; // Used to keep track of the touch coordinates when dragging to measure speed.
var touchstartTarget; // The element which triggered the touchstart.
var selectedIndex = 0; // The current visible page.
var viewPortWidth; // The width of the div that holds the horizontal content.
var isAnimating;
var pageChangedLeft;
// The x coord when the items are reset.
var resetX;
var delayTimeout;
init(method);
function init(options) {
collection = options.data;
renderer = options.renderer;
itemWidth = options.itemWidth;
horizontalGap = options.horizontalGap;
initLayout();
$this[0].addEventListener("touchstart", touchstartHandler);
$this[0].addEventListener("mousedown", touchstartHandler);
viewPortWidth = $this.width();
$this.on("webkitTransitionEnd", transitionEndHandler);
collection.on("add", addItem);
}
// MODIFY ME
function initLayout() {
// Layout five items. The one in the middle is always the selected one.
for (var i = 0; i < 5; i++) {
var viewItem;
if (i > 1 && collection.at(i - 2)) // Start at the one in the middle. Subtract 2 so data index starts at 0.
viewItem = new renderer({model: collection.at(i - 2)});
else
viewItem = new renderer();
viewItem.render().$el.appendTo($this);
viewItem.$el.css("left", itemWidth * i + horizontalGap * i);
viewItem.setState(i != 2 ? "off" : "on");
viewItems.push(viewItem);
}
// Center the first viewItem
resetX = itemWidth * 2 - ($this.width() - itemWidth - horizontalGap * 4) / 2;
setTransformX(-resetX);
}
function getCssLeft($el) {
var left = $el.css("left");
return Number(left.split("px")[0]);
}
// MODIFY ME
function transitionEndHandler() {
if (pageChangedLeft != undefined) {
var viewItem;
if (pageChangedLeft) {
// Move the first item to the end.
viewItem = viewItems.shift();
viewItems.push(viewItem);
viewItem.model = collection.at(selectedIndex + 2);
viewItem.$el.css("left", getCssLeft(viewItems[3].$el) + itemWidth + horizontalGap);
} else {
// Move the last item to the beginning.
viewItem = viewItems.pop();
viewItems.splice(0, 0, viewItem);
viewItem.model = collection.at(selectedIndex - 2);
viewItem.$el.css("left", getCssLeft(viewItems[1].$el) - itemWidth - horizontalGap);
}
viewItem.render();
// Reset the layout of the items.
for (var i = 0; i < 5; i++) {
var viewItem = viewItems[i];
viewItem.$el.css("left", itemWidth * i + horizontalGap * i);
viewItem.setState(i != 2 ? "off" : "on");
}
// Reset the transformX so we don't run into any rendering limits. Can't find a definitive answer for what the limits are.
$this.css("-webkit-transition", "none");
setTransformX(-resetX);
pageChangedLeft = undefined;
}
}
function touchstartHandler(e) {
clearInterval(interval);
wasContentDragged = false;
transitionEndHandler();
// Prevent the default so the window doesn't scroll and links don't open immediately.
e.preventDefault();
// Get a reference to the element which triggered the touchstart.
touchstartTarget = e.target;
// Check for device. If not then testing on desktop.
touchStartX = window.Touch ? e.touches[0].clientX : e.clientX;
// Get the current transformX before the transition is removed.
touchStartTransformX = getTransformX();
// Set the transformX before the animation is stopped otherwise the animation will go to the end coord
// instead of stopping at its current location which is where the drag should begin from.
setTransformX(touchStartTransformX);
// Remove the transition so the content doesn't tween to the spot being dragged. This also moves the animation to the end.
$this.css("-webkit-transition", "none");
// Create an interval to monitor how fast the user is dragging.
interval = setInterval(measureDragSpeed, 20);
document.addEventListener("touchmove", touchmoveHandler);
document.addEventListener("touchend", touchendHandler);
document.addEventListener("mousemove", touchmoveHandler);
document.addEventListener("mouseup", touchendHandler);
}
function measureDragSpeed() {
touchDragCoords.push(getTransformX());
}
function touchmoveHandler(e) {
var deltaX = (window.Touch ? e.touches[0].clientX : e.clientX) - touchStartX;
if (wasContentDragged || Math.abs(deltaX) > MOVE_THRESHOLD) { // Keep track of whether or not the user dragged.
wasContentDragged = true;
setTransformX(touchStartTransformX + deltaX);
}
}
function touchendHandler(e) {
document.removeEventListener("touchmove", touchmoveHandler);
document.removeEventListener("touchend", touchendHandler);
document.removeEventListener("mousemove", touchmoveHandler);
document.removeEventListener("mouseup", touchendHandler);
clearInterval(interval);
e.preventDefault();
if (wasContentDragged) { // User dragged more than MOVE_THRESHOLD so transition the content.
var previousX = getTransformX();
var bSwitchPages;
// Compare the last 5 coordinates
for (var i = touchDragCoords.length - 1; i > Math.max(touchDragCoords.length - 5, 0); i--) {
if (touchDragCoords[i] != previousX) {
bSwitchPages = true;
break;
}
}
// User dragged more than halfway across the screen.
if (!bSwitchPages && Math.abs(touchStartTransformX - getTransformX()) > (viewPortWidth / 2))
bSwitchPages = true;
if (bSwitchPages) {
if (previousX > touchStartTransformX) { // User dragged to the right. go to previous page.
if (selectedIndex > 0) { // Make sure user is not on the first page otherwise stay on the same page.
selectedIndex--;
tweenTo(touchStartTransformX + itemWidth + horizontalGap);
pageChangedLeft = false;
} else {
tweenTo(touchStartTransformX);
pageChangedLeft = undefined;
}
} else { // User dragged to the left. go to next page.
if (selectedIndex + 1 < collection.length) {// Make sure user is not on the last page otherwise stay on the same page.
selectedIndex++;
tweenTo(touchStartTransformX - itemWidth - horizontalGap);
pageChangedLeft = true;
} else {
tweenTo(touchStartTransformX);
pageChangedLeft = undefined;
}
}
} else {
tweenTo(touchStartTransformX);
pageChangedLeft = undefined;
}
} else { // User dragged less than MOVE_THRESHOLD trigger a click event.
var event = document.createEvent("MouseEvents");
event.initEvent("click", true, true);
touchstartTarget.dispatchEvent(event);
}
}
// Returns the x of the transform matrix.
function getTransformX() {
var transformArray = $this.css("-webkit-transform").split(","); // matrix(1, 0, 0, 1, 0, 0)
var transformElement = $.trim(transformArray[4]); // remove the leading whitespace.
return transformX = Number(transformElement); // Remove the ).
}
// Sets the x of the transform matrix.
function setTransformX(value) {
$this.css("-webkit-transform", "translateX("+ Math.round(value) + "px)");
}
function tweenTo(value) {
isAnimating = true;
targetTransformX = value;
// Set the style for the transition.
$this.css("-webkit-transition", "-webkit-transform " + ANIMATION_DURATION + "s");
// Need to set the timing function each time -webkit-transition is set.
// The transition is set to ease-out.
$this.css("-webkit-transition-timing-function", "cubic-bezier(0, 0, 0, 1)");
setTransformX(targetTransformX);
}
// MODIFY ME
function addItem(folio) {
clearTimeout(delayTimeout);
// Create a timeout in case multiple items are added in the same frame.
// When the timeout completes all of the view items will have their model
// updated. The renderer should check to make sure the model is different
// before making any changes.
delayTimeout = setTimeout(function(folio) {
var index = collection.models.indexOf(folio);
var dataIndex = index;
var firstIndex = selectedIndex - 2;
var dataIndex = firstIndex;
var viewItem;
for (var i = 0; i < viewItems.length; i++) {
viewItem = viewItems[i];
if (dataIndex >= 0 && dataIndex < collection.length) {
viewItem.model = collection.at(dataIndex);
viewItem.render();
}
viewItem.setState(i != 2 ? "off" : "on");
dataIndex += 1;
}
}, 200);
}
// Called when the data source has changed. Resets the view with the new data source.
this.setData = function(data) {
$this.empty();
viewItems = [];
collection = data;
selectedIndex = 0;
initLayout();
}
});
} else {
$.error( 'Method ' + method + ' does not exist on Slideshow' );
}
}
})(jQuery);

From what I can make out, you need to simply "flip" the loops that create the sides in the slideshow so that it makes the last slide where it was making the first. It seems to do this in two places.
Then, you will need to amend the code which adds a slide to make it add it before the other slides instead of after.
This sounds an awful lot like homework - it's always best to attempt an answer before asking on here. An example on a site like JSFiddle is also generally appreciated.

Trouble with onclick attribute for img when used in combination with setInterval

I am trying to make images that move around the screen that do something when they are clicked. I am using setInterval to call a function to move the images. Each image has the onclick attribute set. The problem is that the clicks are not registering.
If I take out the setInterval and just keep the images still, then the clicks do register.
My code is here (html, css, JavaScript): https://jsfiddle.net/contini/nLc404x7/4/
The JavaScript is copied here:
var smiley_screen_params = {
smiley_size : 100, // needs to agree with width/height from css file
num_smilies: 20
}
var smiley = {
top_position : 0,
left_position : 0,
jump_speed : 2,
h_direction : 1,
v_direction : 1,
intvl_speed : 10, // advance smiley every x milliseconds
id : "smiley"
}
function randomise_direction(s) {
var hd = parseInt(Math.random()*2);
var vd = parseInt(Math.random()*2);
if (hd === 0)
s.h_direction = -1;
if (vd === 0)
s.v_direction = -1;
}
function plotSmiley(sp /* sp = smiley params */) {
var existing_smiley = document.getElementById(sp.id);
if (existing_smiley !== null)
// delete existing smiley so we can move it
document.getElementById("smileybox").removeChild(existing_smiley);
var smiley_to_plot = document.createElement('img');
smiley_to_plot.setAttribute('src', "http://i.imgur.com/C0BiXJx.png");
smiley_to_plot.setAttribute('id', sp.id);
smiley_to_plot.setAttribute('onclick', "my_click_count()");
smiley_to_plot.style.position = 'absolute';
smiley_to_plot.style.top = sp.top_position + "px";
smiley_to_plot.style.left = sp.left_position + "px";
document.getElementById("smileybox").appendChild(smiley_to_plot);
}
function random_direction_change() {
var r = parseInt(Math.random()*200);
if (r===0)
return true;
else
return false;
}
function moveFace(sp_array /* sp_array = smiley params array */) {
var i;
var sp;
for (i=0; i < sp_array.length; ++i) {
// move ith element
sp = sp_array[i];
if (
(sp.h_direction > 0 && sp.left_position >= smiley_screen_params.width - smiley_screen_params.smiley_size) ||
(sp.h_direction < 0 && sp.left_position <= 0) ||
(random_direction_change())
) {
sp.h_direction = -sp.h_direction; // hit left/right, bounce off (or random direction change)
}
if (
(sp.v_direction > 0 && sp.top_position >= smiley_screen_params.height - smiley_screen_params.smiley_size) ||
(sp.v_direction < 0 && sp.top_position <= 0) ||
(random_direction_change())
) {
sp.v_direction = -sp.v_direction; // hit top/bottom, bounce off (or random direction change)
}
sp.top_position += sp.v_direction * sp.jump_speed;
sp.left_position += sp.h_direction * sp.jump_speed;
plotSmiley(sp);
}
}
if (typeof Object.create !== 'function') {
Object.create = function(o) {
var F = function () {};
F.prototype = o;
return new F();
};
}
function generateFaces() {
var smilies = new Array();
var s;
var i;
var css_smileybox=document.getElementById("smileybox");
var sb_style = getComputedStyle(css_smileybox, null);
// add info to the screen params
smiley_screen_params.width = parseInt(sb_style.width);
smiley_screen_params.height = parseInt(sb_style.height);
// create the smileys
for (i=0; i < smiley_screen_params.num_smilies; ++i) {
s = Object.create(smiley);
s.id = "smiley" + i;
s.top_position = parseInt(Math.random() * (smiley_screen_params.height - smiley_screen_params.smiley_size)),
s.left_position = parseInt(Math.random() * (smiley_screen_params.width - smiley_screen_params.smiley_size)),
randomise_direction(s);
smilies.push(s);
}
setInterval( function(){ moveFace(smilies) }, smiley.intvl_speed );
}
var click_count=0;
function my_click_count() {
++click_count;
document.getElementById("mg").innerHTML = "Number of clicks: " + click_count;
}
generateFaces();
The generateFaces() will generate parameters (for example, coordinates of where they are placed) for a bunch of smiley face images. The setInterval is within this function, and calls the moveFace function to make the smiley faces move at a fixed interval of time. moveFace computes the new coordinates of each smiley face image and then calls plotSmiley to plot each one on the screen in its new location (removing it from the old location). The plotSmiley sets the onclick attribute of each image to call a dummy function just to see if the clicks are registering.
Thanks in advance.

This is not a complete answer but it could give you some perspective to improve your code.
First of all, your idea of deleting the existing img so wrong. If it does exist, all you need is to just change its position so instead of this
if (existing_smiley !== null)
// delete existing smiley so we can move it
document.getElementById("smileybox").removeChild(existing_smiley);
you should do something like this:
if (existing_smiley !== null)
var smiley_to_plot = existing_smiley;
else {
var smiley_to_plot = document.createElement('img');
smiley_to_plot.setAttribute('src', "http://i.imgur.com/C0BiXJx.png");
smiley_to_plot.setAttribute('id', sp.id);
smiley_to_plot.style.position = 'absolute';
document.getElementById("smileybox").appendChild(smiley_to_plot);
smiley_to_plot.addEventListener('click', my_click_count);
}
smiley_to_plot.style.top = sp.top_position + "px";
smiley_to_plot.style.left = sp.left_position + "px";
As you can see new image is only being added if it's not already there. Also notice that adding events by using .setAttribute('onclick', "my_click_count()"); is not a good way to do. You should use .addEventListener('click', my_click_count); like I did.
Like I said this is not a complete answer but at least this way they response to the click events now.
FIDDLE UPDATE
Good luck!