Develop Reference

Main Page Background Image Slider Question

I am using JavaScript to change a background image on a page. It works, but there is a minor problem. For a split second, between images there is nothing (just white screen). Again it lasts just a split second but it is annoying.
How can I get one image to fade out while the other is fading in?
I've tried adjusting the fadeIn and fadeOut time, but I realized the second image doesn't start to fadeIn until the first completely fades out.
$(document).ready(function(){
var imgArr = new Array(
'images/home/background_image_1.jpg',
'images/home/background_image_2.jpg',
'images/home/background_image_3.jpg'
);
var preloadArr = new Array();
var i;
/* preload images */
for(i=0; i < imgArr.length; i++){
preloadArr[i] = new Image();
preloadArr[i].src = imgArr[i];
}
var currImg = 1;
var intID = setInterval(changeImg, 20000);
/* image rotator */
function changeImg(){
$('#background-image').fadeOut(1500, function(){
$(this).css('background','url(' + preloadArr[currImg++%preloadArr.length].src +')')
.css("background-position", "center").css("background-repeat", "no-repeat").css("background-size", "cover");
}).fadeIn(1500);
}
});
Any help would be greatly appreciated

Jquery's .fadeOut() has optional parameters .fadeOut( [duration ] [, complete callback ] ).
Where complete callback is the function that will run when the fading animation is done. So that split second is actually the duration you've passed to your .fadeOut() function.
Your code takes 1.5s to perform the animation and then only when it's done then it calls your function that fades in another background image. That's what causing the delay.
An alternative option would be to create seperate executions of .fadeOut() and .fadeIn(). And please don't apply the images on the same element, because you won't achieve it that way. You will need to create an <img> for each picture and set position: absolute on them to position them on top of each other. and then apply fade animation on each <img>
You might need this for revision here

Slideshow transition in javascript

I cant seem to get this slide show to work with javascript. the image fades in and out correctly on the first image but when transitioning for the second image it seems to immediately skip to the image instead of transition like the previous.
<script type="text/javascript">
var images = ["image1.png", "image2.png", "image3.jpg"];
var imagecount = 0;
window.setInterval(setImage,5000);
function setImage(){
$('.bgimage').fadeIn(5000);
$('.bgimage').css('background-image','url('+images[imagecount]+')');
$('.bgimage').fadeOut(5000);
imagecount++;
if(imagecount > 2){
imagecount=0;
}
}
</script>

Without seeing the html structure or a fiddle, it's hard to trouble-shoot with any accuracy. I'm guessing the issue is probably with your fadeIn and fadeOut calls, as they are currently set to animate for a full 5 seconds each, and animating at the same time as one another (They are called asynchronously). Instead, you should adjust the fadeIn method to execute after the fadeOut finishes using the built-in jQuery callback. Like so:
$('.bgimage').fadeOut(500, function() {
$('.bgimage').css('background-image','url('+images[imagecount]+')');
$('.bgimage').fadeIn(500);
});
I've also switched the order of your fade calls, as you should fade out the image, then update it (while it's not visible), then fade it back in. Your interval should still work the way you want, running every 5 seconds. Now the transitions won't take a full 5 seconds to animate.

Fade in a class before fading out completely

I would like to change an image in my site with fading effect. The thing is that I am using two different classes for the same div, so actually I want to fade out one class and in the meanwhile start fading in the second class, before the first one has been completely removed.
HTML:
<div id="background_image" class="day"></div>
CSS:
.day{
background: url(day.png);
}
.night {
background: url(night.png);
}
JQuery:
setTimeout(function(){
if($("#background_image").hasClass("day")){
$("#background_image").fadeOut(function() {
$(this).removeClass("day");
});
$("#Landscape").fadeIn(function() {
$(this).addClass("night");
});
}else{
$("#background_image").fadeOut(function() {
$(this).removeClass("night");
});
$("#Landscape").fadeIn(function() {
$(this).addClass("day");
});
}
}, 5000);
But this code makes the image "day.png" first to disappear completely and then the "night.png" comes which is not what I want.
Is there a way to fade out the class "day" and start fade it "night" without having a blank space between the fading? Thanks in advance

It seems that what you're trying to do is cross-fading. This is normally done using 2 divs. If this is for the entire background, then I suggest http://srobbin.com/jquery-plugins/backstretch/. You can take a look at their implementation to narrow it down to just a div if you don't need it to cover the entire background.
This is how I solved it for a similar case.
var images = [
"/content/images/crane1.jpg",
"/content/images/crane2.jpg",
"/content/images/crane-interior.jpg"
];
// The index variable will keep track of which image is currently showing
var index = 0;
// Call backstretch for the first time,
// In this case, I'm settings speed of 500ms for a fadeIn effect between images.
$.backstretch(images[index], { speed: 500 });
// Set an interval that increments the index and sets the new image
// Note: The fadeIn speed set above will be inherited
setInterval(function () {
index = (index >= images.length - 1) ? 0 : index + 1;
$.backstretch(images[index]);
}, 5000);
EDIT:
For non-full background, take a look at this post Crossfade Background images using jQuery
Also take a look at this, might be closer to your scenario Cross fade background-image with jQuery

Change a div background with jQuery

I need to change my background div with some other images.
I want that first, myDiv load the first background image on css style, and then within 2/3 seconds of delay add a fade effect change the background image.
If it's possible, I need to do this with jQuery.

You cannot do fade or any other transitions directly on the background image. You can however add another div with second image as its background and fadeOut() the original one.

Does this do what you you want?
http://jqueryfordesigners.com/image-loading/
EDIT: A bit more Googling - this sounds like what you are trying to do...
http://www.magneticwebworks.com/jquery-rotating-page-background/
Edit: another go - THis? http://css-tricks.com/forums/discussion/9621/solved-is-it-possible-to-add-jquery-cycle-to-background-imagess/p1

this is not fade effect but you can delay and change background image like this.
function changebackground(){
$('#divID').css("background-image", "url(/myimage.jpg)");
}
setTimeout(function() { changebackground();}, 3000);

this might be good workaround
http://jquery.malsup.com/cycle/
after you position on top divs with cycle it can be your background - cycle.js give's you lot of options.
if you want only rotate image's in bacground you must first preload that image and second you must put it in other div so that both divs can animate.

There is no support for this, even if you add all the functionality of jQuery UI.
You could append a temporary image, absolutely positioned inside the div for which u want to change background. Let the image fade in, and once it's fully opaque, swap background image for the div. This will be problematic if you have a repeated background, however.
var im1 = 'picture1.png';
var im2 = 'picture2.png';
$('#divID').css({'background-image': 'url("'+im1+'")', 'position': 'relative'});
$('#divID').on('click', function() {
var img = $('<img />', {
src: im2,
}).css({
position: 'absolute',
top: 0,
left: 0
}).hide();
$(this).append(img);
img.fadeIn('slow', function() {
$(this).parent().css('background-image', 'url("'+im2+'")');
$(this).remove();
});
});
Of course, you should move the CSS I included in my script to a .css file, and use a class instead, for more readable code.

jQuery: simultaneously fadeIn and fadeOut

the following code which is called periodically by setInterval performs the following sequence:
1. fade in an image for 750 msec
2. diplay it for 6 secs
3. fade out the image for 750 msec
4. randomly select another image (function randomPic)
5. fade in for 750 msec and so on:
$("#_fadee_").fadeIn(750, function() {
$("#_fadee_").delay(6000).fadeOut(750, randomPic);
});
You can see the effect here. How can I get the fadeOut of the old image and the fadeIn of the new one to run simultaneously?
Thanks, Ralf

Basically, you need to load the new image in another div that has a z-index beneath the image fading out. It's not that it's fading in simultaneously, it's just uncovered as the initial is fading out. Once the top div is faded out completely, you load the mew image into it and return its opacity to 1 so that it covers the div that you will load the next image into. In pseudocode it would look something like this:
var fadeO = function () {
var $fo = $('#_fadeO_');
var $fi = $('#_fadeI_');
var newImg = // load image here;
$fi.html(newImg);
$fo.fadeOut(1500, function() {
// put #_fadeO_ back on top with new image
$fo.html(newImg);
$fo.css({'display':'block', 'opacity':1});
// call function again after 6 seconds
setTimeout(fadeO, 6000);
});
};
fadeO();
...but I made a fiddle of it so you could see it in action, switching background colors instead of image contents. You should be able to get the idea of how to do the same with loaded images based on the above pseudo-code and how the HTML, CSS, and JS is set up here:
http://jsfiddle.net/UbmS9/

If you aren't doing anything else you could do this:
$("#_fadee_").fadeIn(750, function() {
setTimeout(function() {
$("#_fadee_").fadeOut(750, randomPic);
// Start fading in your other pic
}, 6000);
});
Alternatively, if they're both being displayed in the same area, you could fade in, and once faded in set the background image to the next image. Then, once that's faded out, set the background to the next, and so on.