I came across the following code and was wondering what the IMG.active refers too. If someone could help, could you go line by line and write ments too?
function slideSwitch() {
//what does this and the next line do?
var $active = $('#slideshow IMG.active');
if ( $active.length == 0 ) $active = $('#slideshow IMG:last');
//what is going on here?
var $next = $active.next().length ? $active.next()
: $('#slideshow IMG:first');
// unment the 3 lines below to pull the images in random order
// var $sibs = $active.siblings();
// var rndNum = Math.floor(Math.random() * $sibs.length );
// var $next = $( $sibs[ rndNum ] );
//can someone elaborate on these lines?
$active.addClass('last-active');
$next.css({opacity: 0.0})
.addClass('active')
.animate({opacity: 1.0}, 1000, function() {
$active.removeClass('active last-active');
});
}
$(function() {
setInterval( "slideSwitch()", 5000 );
});
I think this code is trying to pull images from underneath each image?
I came across the following code and was wondering what the IMG.active refers too. If someone could help, could you go line by line and write ments too?
function slideSwitch() {
//what does this and the next line do?
var $active = $('#slideshow IMG.active');
if ( $active.length == 0 ) $active = $('#slideshow IMG:last');
//what is going on here?
var $next = $active.next().length ? $active.next()
: $('#slideshow IMG:first');
// unment the 3 lines below to pull the images in random order
// var $sibs = $active.siblings();
// var rndNum = Math.floor(Math.random() * $sibs.length );
// var $next = $( $sibs[ rndNum ] );
//can someone elaborate on these lines?
$active.addClass('last-active');
$next.css({opacity: 0.0})
.addClass('active')
.animate({opacity: 1.0}, 1000, function() {
$active.removeClass('active last-active');
});
}
$(function() {
setInterval( "slideSwitch()", 5000 );
});
I think this code is trying to pull images from underneath each image?
Share Improve this question edited Oct 30, 2014 at 19:03 locoboy asked Nov 15, 2011 at 19:57 locoboylocoboy 39.1k73 gold badges188 silver badges263 bronze badges 2- Looks like carousel code sorgalla./projects/jcarousel/examples/static_circular.html – lsl Commented Nov 15, 2011 at 20:03
- +1 ... I had fun to figure out and build the gallery using your code! – Roko C. Buljan Commented Nov 15, 2011 at 21:26
3 Answers
Reset to default 5IMG.active refers to all image tags (<img />) with the active class, so:
<img src="..." class="active" />
--
function slideSwitch() {
var $active = $('#slideshow IMG.active');//get all `img` elements with the `active` class within the #slideshow element
if ( $active.length == 0 ) $active = $('#slideshow IMG:last');//if no elements were selected on the last line, then set the active slide (`$active`) to the last image in the slideshow
var $next = $active.next().length ? $active.next()
: $('#slideshow IMG:first');//check to see if there is another image after the current $active element, if not then set the $next variable to the first image in the slideshow
// unment the 3 lines below to pull the images in random order
// var $sibs = $active.siblings();
// var rndNum = Math.floor(Math.random() * $sibs.length );
// var $next = $( $sibs[ rndNum ] );
$active.addClass('last-active');//add the `last-active` class to the current $active element
$next.css({opacity: 0.0})
.addClass('active')
.animate({opacity: 1.0}, 1000, function() {
$active.removeClass('active last-active');
});//these lines set the $next element to invisible, adds the `active` class, then animates its opacity to show the image, after the animation is plete it removes the `active` and `last-active` classes from the $next element.
}
//this runs the function above on an interval of 5sec when the `document.ready` event fires
$(function() {
setInterval( "slideSwitch()", 5000 );
});
The ments are added below. Note: $active.next() also selects non-image elements. This is probably not intended. If you want to select the next image element, use $active.nextAll("img:first") instead.
function slideSwitch() {
// Selects all <img class="active"> elements which are a child of
// an element with id="slideshow"
var $active = $('#slideshow IMG.active');
// If the collection $active contains no elements, select the last
// <img> element which is a child of <.. id=slideshow>
if ( $active.length == 0 ) $active = $('#slideshow IMG:last');
// If there's another element after <img>, select it. Otherwise, select
// first <img>
var $next = $active.next().length ? $active.next()
: $('#slideshow IMG:first');
// Add `class=last-active` to the selected element.
$active.addClass('last-active');
$next.css({opacity: 0.0}) // Set opacity 0
.addClass('active') // Set class `active`
.animate({opacity: 1.0}, 1000, function() { //Animate
$active.removeClass('active last-active');
});
}
// Create an interval when the document is ready
$(function() {
setInterval( "slideSwitch()", 5000 );
});
//what is going on here?
var $next = $active.next().length ? $active.next()
: $('#slideshow IMG:first');
This is a ternary operator. Basically, if the next() function returns anything other than 0, the next image is assigned as whatever next() returns. Otherwise, it uses the first img element in the #slideshow element.
//can someone elaborate on these lines?
$active.addClass('last-active');
This adds the class of last-active to whichever element currently has a class of active.