jCarousel

Riding carousels with jQuery

Author: Jan Sorgalla
Version: 0.2.8 (Changelog)
Download: jcarousel.tar.gz or jcarousel.zip
Source Code: http://github.com/jsor/jcarousel
Bugtracker: http://github.com/jsor/jcarousel/issues
Licence: Dual licensed under the MIT and GPL licenses.

Contents

  1. Introduction
  2. Examples
  3. Getting started
  4. Dynamic content loading
  5. Accessing the jCarousel instance
  6. Defining the number of visible items
  7. Configuration
  8. Credits

Introduction

jCarousel is a jQuery plugin for controlling a list of items in horizontal or vertical order. The items, which can be static HTML content or loaded with (or without) AJAX, can be scrolled back and forth (with or without animation).

Examples

The following examples illustrate the possibilities of jCarousel:

Getting started

To use the jCarousel component, include the jQuery library, the jCarousel source file and a jCarousel skin stylesheet file inside the <head> tag of your HTML document:

<script type="text/javascript" src="/path/to/jquery-1.4.2.min.js"></script>
<script type="text/javascript" src="/path/to/lib/jquery.jcarousel.min.js"></script>
<link rel="stylesheet" type="text/css" href="/path/to/skin/skin.css" />

The download package contains some example skin packages. Feel free to build your own skins based on it.

jCarousel expects a very basic HTML markup structure inside your HTML document:

<ul id="mycarousel" class="jcarousel-skin-name">
   <!-- The content goes in here -->
</ul>

jCarousel automatically wraps the required HTML markup around the list. The class attribute applies the jCarousel skin "name" to the carousel.

To setup jCarousel, add the following code inside the <head> tag of your HTML document:

<script type="text/javascript">
jQuery(document).ready(function() {
    jQuery('#mycarousel').jcarousel({
        // Configuration goes here
    });
});
</script>

jCarousel accepts a lot of configuration options, see chapter "Configuration" for further informations.

After jCarousel has been initialised, the fully created markup in the DOM is:

<div class="jcarousel-skin-name">
  <div class="jcarousel-container">
    <div class="jcarousel-clip">
      <ul class="jcarousel-list">
        <li class="jcarousel-item-1">First item</li>
        <li class="jcarousel-item-2">Second item</li>
      </ul>
    </div>
    <div disabled="disabled" class="jcarousel-prev jcarousel-prev-disabled"></div>
    <div class="jcarousel-next"></div>
  </div>
</div>

As you can see, there are some elements added which have assigned classes (in addition to the classes you may have already assigned manually). Feel free to design your carousel with the classes you can see above.

Note:

Dynamic content loading

By passing the callback function itemLoadCallback as configuration option, you are able to dynamically create <li> items for the content.

<script type="text/javascript">
jQuery(document).ready(function() {
    jQuery('#mycarousel').jcarousel({
        itemLoadCallback: itemLoadCallbackFunction
    });
});
</script>

itemLoadCallbackFunction is a JavaScript function that is called when the carousel requests a set of items to be loaded. Two parameters are passed: The instance of the requesting carousel and a flag which indicates the current state of the carousel ('init', 'prev' or 'next').

<script type="text/javascript">
function itemLoadCallbackFunction(carousel, state)
{
    for (var i = carousel.first; i <= carousel.last; i++) {
        // Check if the item already exists
        if (!carousel.has(i)) {
            // Add the item
            carousel.add(i, "I'm item #" + i);
        }
    }
};
</script>

jCarousel contains a convenience method add() that can be passed the index of the item to create and the innerHTML string of the item to be created. If the item already exists, it just updates the innerHTML. You can access the index of the first and last visible element by the public variables carousel.first and carousel.last.

Accessing the jCarousel instance

The instance of the carousel will be stored with the data() method of jQuery under the key jcarousel for a simple access.

If you have created a carousel like:

jQuery(document).ready(function() {
    jQuery('#mycarousel').jcarousel();
});

You can access the instance with:

var carousel = jQuery('#mycarousel').data('jcarousel');

You can also access methods of the instance directly, for example the add() method: 

var index = 1;
var html = 'My content of item no. 1';
jQuery('#mycarousel').jcarousel('add', index, html);

Defining the number of visible items

Sometimes people are confused how to define the number of visible items because there is no option for this as they expect (Yes, there is an option visible, we discuss this later).

You simply define the number of visible items by defining the width (or height) with the class .jcarousel-clip (or the more distinct .jcarousel-clip-horizontal and .jcarousel-clip-vertical classes) in your skin stylesheet.

This offers a lot of flexibility, because you can define the width in pixel for a fixed carousel or in percent for a flexible carousel (This example shows a carousel with a clip width in percent, resize the browser to see it in effect).

So, why there is an option visible? If you set the option visible, jCarousel sets the width of the visible items to always make this number of items visible. Open this example and resize your browser window to see it in effect.

Configuration

jCarousel accepts a list of options to control the appearance and behaviour of the carousel. Here is the list of options you may set:

Property Type Default Description
vertical bool false Specifies wether the carousel appears in horizontal or vertical orientation. Changes the carousel from a left/right style to a up/down style carousel.
rtl bool false Specifies wether the carousel appears in RTL (Right-To-Left) mode.
start integer 1 The index of the item to start with.
offset integer 1 The index of the first available item at initialisation.
size integer Number of existing <li> elements if size is not passed explicitly The number of total items.
scroll integer 3 The number of items to scroll by.
visible integer null If passed, the width/height of the items will be calculated and set depending on the width/height of the clipping, so that exactly that number of items will be visible.
animation mixed "fast" The speed of the scroll animation as string in jQuery terms ("slow" or "fast") or milliseconds as integer (See jQuery Documentation). If set to 0, animation is turned off.
easing string null The name of the easing effect that you want to use (See jQuery Documentation).
auto integer 0 Specifies how many seconds to periodically autoscroll the content. If set to 0 (default) then autoscrolling is turned off.
wrap string null Specifies whether to wrap at the first/last item (or both) and jump back to the start/end. Options are "first", "last", "both" or "circular" as string. If set to null, wrapping is turned off (default).
initCallback function null JavaScript function that is called right after initialisation of the carousel. Two parameters are passed: The instance of the requesting carousel and the state of the carousel initialisation (init, reset or reload).
setupCallback function null JavaScript function that is called right after the carousel is completely setup. One parameter is passed: The instance of the requesting carousel.
itemLoadCallback function null JavaScript function that is called when the carousel requests a set of items to be loaded. Two parameters are passed: The instance of the requesting carousel and the state of the carousel action (prev, next or init). Alternatively, you can pass a hash of one or two functions which are triggered before and/or after animation: 
itemLoadCallback: {
  onBeforeAnimation: callback1,
  onAfterAnimation: callback2
}
itemFirstInCallback function null JavaScript function that is called (after the scroll animation) when an item becomes the first one in the visible range of the carousel. Four parameters are passed: The instance of the requesting carousel and the <li> object itself, the index which indicates the position of the item in the list and the state of the carousel action (prev, next or init). Alternatively, you can pass a hash of one or two functions which are triggered before and/or after animation: 
itemFirstInCallback: {
  onBeforeAnimation: callback1,
  onAfterAnimation: callback2
}
itemFirstOutCallback function null JavaScript function that is called (after the scroll animation) when an item isn't longer the first one in the visible range of the carousel. Four parameters are passed: The instance of the requesting carousel and the <li> object itself, the index which indicates the position of the item in the list and the state of the carousel action (prev, next or init). Alternatively, you can pass a hash of one or two functions which are triggered before and/or after animation: 
itemFirstOutCallback: {
  onBeforeAnimation: callback1,
  onAfterAnimation: callback2
}
itemLastInCallback function null JavaScript function that is called (after the scroll animation) when an item becomes the last one in the visible range of the carousel. Four parameters are passed: The instance of the requesting carousel and the <li> object itself, the index which indicates the position of the item in the list and the state of the carousel action (prev, next or init). Alternatively, you can pass a hash of one or two functions which are triggered before and/or after animation: 
itemLastInCallback: {
  onBeforeAnimation: callback1,
  onAfterAnimation: callback2
}
itemLastOutCallback function null JavaScript function that is called when an item isn't longer the last one in the visible range of the carousel. Four parameters are passed: The instance of the requesting carousel and the <li> object itself, the index which indicates the position of the item in the list and the state of the carousel action (prev, next or init). Alternatively, you can pass a hash of one or two functions which are triggered before and/or after animation: 
itemLastOutCallback: {
  onBeforeAnimation: callback1,
  onAfterAnimation: callback2
}
itemVisibleInCallback function null JavaScript function that is called (after the scroll animation) when an item is in the visible range of the carousel. Four parameters are passed: The instance of the requesting carousel and the <li> object itself, the index which indicates the position of the item in the list and the state of the carousel action (prev, next or init). Alternatively, you can pass a hash of one or two functions which are triggered before and/or after animation: 
itemVisibleInCallback: {
  onBeforeAnimation: callback1,
  onAfterAnimation: callback2
}
itemVisibleOutCallback function null JavaScript function that is called (after the scroll animation) when an item isn't longer in the visible range of the carousel. Four parameters are passed: The instance of the requesting carousel and the <li> object itself, the index which indicates the position of the item in the list and the state of the carousel action (prev, next or init). Alternatively, you can pass a hash of one or two functions which are triggered before and/or after animation: 
itemVisibleOutCallback: {
  onBeforeAnimation: callback1,
  onAfterAnimation: callback2
}
animationStepCallback function null JavaScript function that is called after each animation step. This function is directly passed to jQuery's .animate() method as the step parameter. See the jQuery documentation for the parameters it will receive.
buttonNextCallback function null JavaScript function that is called when the state of the 'next' control is changing. The responsibility of this method is to enable or disable the 'next' control. Three parameters are passed: The instance of the requesting carousel, the control element and a flag indicating whether the button should be enabled or disabled.
buttonPrevCallback function null JavaScript function that is called when the state of the 'previous' control is changing. The responsibility of this method is to enable or disable the 'previous' control. Three parameters are passed: The instance of the requesting carousel, the control element and a flag indicating whether the button should be enabled or disabled.
buttonNextHTML string <div></div> The HTML markup for the auto-generated next button. If set to null, no next-button is created.
buttonPrevHTML string <div></div> The HTML markup for the auto-generated prev button. If set to null, no prev-button is created.
buttonNextEvent string "click" Specifies the event which triggers the next scroll.
buttonPrevEvent string "click" Specifies the event which triggers the prev scroll.
itemFallbackDimension integer null If, for some reason, jCarousel can not detect the width of an item, you can set a fallback dimension (width or height, depending on the orientation) here to ensure correct calculations.

Credits

Thanks to John Resig for his fantastic jQuery library.
jCarousel is inspired by the Carousel Component written by Bill Scott.