jquery ui 1 8 wellman 2011 08 Lập trình Java

jQuery UI 1.8 The User Interface Library for jQuery Build highly interactive web applications with ready-to-use widgets from the jQuery User Interface Library Dan Wellman BIRMINGHAM -

jQuery UI 1.8

The User Interface Library for jQuery

Build highly interactive web applications with

ready-to-use widgets from the jQuery User

Interface Library

Dan Wellman

BIRMINGHAM - MUMBAI

jQuery UI 1.8

The User Interface Library for jQuery

Copyright © 2011 Packt Publishing

All rights reserved No part of this book may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, without the prior written permission of the publisher, except in the case of brief quotations embedded in critical articles or reviews

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of the information presented However, the information contained in this book is sold without warranty, either express or implied Neither the author, nor Packt Publishing, and its dealers and distributors will be held liable for any damages caused or alleged to be caused directly or indirectly by this book

Packt Publishing has endeavored to provide trademark information about all of the companies and products mentioned in this book by the appropriate use of capitals However, Packt Publishing cannot guarantee the accuracy of this information.First published: August 2011

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Production Coordinators

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Cover Work

Aparna Bhagat Nilesh Mohite

About the Author

Dan Wellman is an author and web developer based on the South Coast of the UK

By day he works alongside some of the most talented people he has had the pleasure

of calling colleagues, for a small, yet accomplished digital agency called Design Haus By night he writes books and tutorials on a range of front-end topics He is hopelessly addicted to jQuery His life is enriched by his four wonderful children,

a beautiful wife, and a close circle of family and friends This is his sixth book

Thanks to everyone who was involved in the book, the editorial team

at Packt, the reviewers, and the hugely talented team responsible

for jQuery UI Props to my friends Steev Bishop, Andrew Herman,

Dan Goodall, Aaron Matheson, James Zabiela, Jon Adams, Eamon

O'Donoghue, and Dan Isles

About the Reviewers

Vijay Joshi is a programmer with over six years of experience on various

platforms He discovered his passion for open source four years back when he started playing with PHP on a hobby project after completing his Masters in

Computer Applications

Vijay is now a freelance web developer, independent consultant for a few selected companies, and a blogger at http://vijayjoshi.org He specializes in developing custom web applications, mashups, creating apps using PHP frameworks, and enhancing existing web apps using PHP and front-end libraries like jQuery, jQUI, and so on

Vijay is also the author of PHP jQuery Cookbook and a technical reviewer of

PHP AJAX Cookbook both of which have been published by Packt

Outside of work, he enjoys reading, trekking, and sometimes gets obsessed

with fitness

Jake Kronika is a web designer and developer with over fifteen years of

experience, and brings to this book a strong background in front-end development with JavaScript and jQuery, as well as significant training in server-side languages and frameworks

Having earned a Bachelors of Science degree in Computer Science from Illinois Wesleyan University in 2005, with a minor in Business Administration, he went on

to become Senior User Interface (UI) Specialist for Imaginary Landscape, LLC, a small web development firm in the Ravenswood neighborhood on the north side of Chicago In this role, the foundations of his strengths in Cascading Style Sheets (CSS) and JavaScript (JS) were honed and finely tuned

From there, Jake went on to work for the Sun-Times News Group, owner of the Chicago Sun-Times and numerous suburban newspapers in Chicagoland It was

in this role that he was initially exposed and rapidly gained expert skills with the jQuery framework for JS

Following intermediate positions as Technology Consultant with Objective Arts, Inc, and as UI Prototyper for JP Morgan Chase, Jake moved across the contiguous United States to Seattle, WA, where he assumed his current role of Senior UI Software Engineer with the Cobalt Group, a marketing division of ADP's Dealer Services Since 1999, he has also operated Gridline Design & Development (so named in 2009),

a sole proprietorship for web design, development, and administration

Jake has also reviewed Django JavaScript Integration: AJAX and jQuery, a Packt Publishing text authored by Jonathan Howard and published in January of 2011

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For my wonderful mother Sue

Table of Contents

Chapter 1: Introducing jQuery UI 7

Setting up a development environment 11 The structure of the library 12

Chapter 2: The CSS Framework and Other Utilities 25

The files that make up the framework 25

jquery.ui.all.css 27jquery.ui.base.css 27jquery.ui.core.css 27

The individual component framework files 29

jquery.ui.theme.css 29

Linking to the required framework files 30

Table of Contents

[ ii ]

Using the position utility 43

Chapter 3: Using the Tabs Widget 61

Applying a custom theme to the tabs 66

Selecting a tab 69Disabling a tab 70Transition effects 70Collapsible tabs 71

Binding to events 74

Enabling and disabling tabs 76Adding and removing tabs 77Simulating clicks 78Creating a tab carousel 79Getting and setting options 81

Changing the URL of a remote tab's content 83

Displaying data obtained via JSONP 84

Table of Contents

[ iii ]

Changing the default active header 96Filling the height of its container 98Accordion animation 99

Controlling a dialog programmatically 127

Toggling the dialog 127

Getting data from the dialog 128

Chapter 7: The Datepicker Widget 159

Configurable options of the datepicker 162

Basic options 164Minimum and maximum dates 166Changing the elements in the datepicker UI 167Adding a trigger button 169Configuring alternative animations 171Multiple months 172Changing the date format 174Updating an additional input element 176Localization 177Callback properties 180

Selecting a date programmatically 185Showing the datepicker in a dialog box 186

Chapter 8: The Progressbar Widget 193

The default progressbar implementation 194 Progressbar's configuration options 195

Setting progressbar's value 195

Rich uploads with progressbar 203

Chapter 9: The Button and Autocomplete Widgets 209

Standard implementations 210

Configurable options 212Button icons 213

Working with local data sources 221

Using an array of objects as the data source 223

Configurable autocomplete options 224

Configuring minimum length 225 Appending the suggestion list to an alternative element 225

Autocomplete events 226Autocomplete methods 228Working with remote data sources 229

Using a string as the value of the source option 229 Using a function as the value of the source option 230

Displaying HTML in the list of suggestions 236

Chapter 10: Drag and Drop 241

The deal with drag and droppables 242

A basic drag implementation 243

Configuring draggable options 244

Using the configuration options 247Resetting dragged elements 248Drag handles 249Helper elements 250Constraining the drag 252

Configurable options of the selectable component 306

Filtering selectables 306Canceling the selection 308

Working with vast amounts of selectables 311

Refreshing selectables 313

Styling the image selector 317Adding the behaviour 318

Chapter 13: The Sortables Component 323

Configuring sortable options 326

Placeholders 332Sortable helpers 333Sortable items 334Connected lists 335

Using color animations 354Using class transitions 356Advanced easing 358

Highlighting specified elements 358

Additional effect arguments 360

Dropping elements onto the page 373 Sliding elements open or closed 375

Modern web application user interface design requires rapid development and proven results jQuery UI, a trusted suite of official plugins for the jQuery JavaScript library, gives you a solid platform on which you can build rich and engaging

interfaces with maximum compatibility, stability, and a minimum of time and effort.jQuery UI has a series of ready-made, great-looking user interface widgets and

a comprehensive set of core interaction helpers designed to be implemented in

a consistent and developer-friendly way With all this, the amount of code that you need to write personally to take a project from conception to completion is drastically reduced

Specially revised for version 1.8+ of jQuery UI, this book has been written to

maximize your experience with the library by breaking down each component and walking you through examples that progressively build upon your knowledge, taking you from beginner to advanced usage in a series of easy-to-follow steps

In this book, you'll learn how each component can be initialized in a basic default implementation and then see how easy it is to customize its appearance and

configure its behavior to tailor it to the requirements of your application You'll look

at the configuration options and the methods exposed by each component's API to see how these can be used to bring out the best of the library

Events play a key role in any modern web application if it is to meet the expected minimum requirements of interactivity and responsiveness, and each chapter will show you the custom events fired by the component covered and how these events can be intercepted and acted upon

[ 2 ]

What this book covers

Chapter 1, Introducing jQuery UI, lets you find out exactly what the library is, where

it can be downloaded from, and how the files within it are structured We also look

at ThemeRoller, which browsers support the library, how it is licensed, and how the API has been simplified to give the components a consistent and easy-to-use programming model

Chapter 2, The CSS Framework and Other Utilities, looks in detail at the extensive CSS

framework, which provides a rich environment for integrated theming through Themeroller, or allows developers to easily supply their own custom themes or skins We also cover the new position utility, as well as a whole section dedicated

to writing your own jQuery UI plugins using the widget factory

Chapter 3, Using the Tabs Component, looks at the first widget, which is the tabs

component, a simple but effective means of presenting structured content in an engaging and interactive widget

Chapter 4, The Accordion Widget, looks at the accordion widget, another component

dedicated to the effective display of content Highly engaging and interactive, the accordion makes a valuable addition to any web page and its API is exposed in full

to show exactly how it can be used

Chapter 5, The Dialog, focuses on the dialog widget The dialog behaves in the same

way as a standard browser alert, but it does so in a much less intrusive and more visitor-friendly manner We look at how it can be configured and controlled to provide maximum benefit and appeal

Chapter 6, The Slider Widget, provides a less commonly used, but no less valuable

user interface tool for collecting input from your visitors We look closely at its API throughout this chapter to see the variety of ways in which it can be implemented

Chapter 7, The Datepicker Widget, looks at the date picker This component packs a

huge amount of functionality into an attractive and highly usable tool, allowing your visitors to effortlessly select dates We look at the wide range of configurations that its API makes possible as well as seeing how easy common tasks such as skinning and localization are made

Chapter 8, The Progressbar Widget, looks at the progressbar widget, examining its

compact API and seeing a number of ways in which it can be put to good use in our web applications

[ 3 ]

Chapter 9, The Button and Autocomplete Widgets, looks at the brand new button, and

recently revivied autocomplete Longtime users of the library will remember the autocomplete from a previous version of the library The widget is now back, fully updated to fit in with the latest version of the library and in this chapter we get to see how it can be used to great effect

Chapter 10, Drag and Drop, begins to look at the low-level interaction helpers,

tackling first the related drag-and-droppable components We look at how they can be implemented individually and how they can be used together to enhance your user interfaces

Chapter 11, The Resizable Component, looks at the resizing component and how it is

used with the dialog widget seen earlier in the book We see how it can be applied

to any element on the page to allow it be resized in a smooth and attractive way

Chapter 12, The Selectables Component, looks at the selectable component, which allows

us to add behavior to elements on the page and allows them be selected individually

or as a group We see that this is one component that really brings the desktop and the browser together as application platforms

Chapter 13, The Sortables Component, looks at the final interaction helper in this

chapter–the sortable component This is an especially effective component that allows you to create lists on a page that can be reordered by dragging items to a new position on the list This is another component that can really help you to add a high level of professionalism and interactivity to your site with a minimum of effort

Chapter 14, UI Effects, the last chapter of the book, is dedicated solely to the special

effects that are included with the library We look at an array of different effects that allow you to show, hide, move, and jiggle elements in a variety of attractive and appealing animations

What you need for this book

All you need to work through most of the examples in this book is a simple text or code editor and a browser One or two of the more advanced examples rely on PHP, but for convenience, I've put these examples up on my site for you to use if need be You can find them at http://danwellman.co.uk/examples/jqueryui/

[ 4 ]

Who this book is for

This book is for front-end developers who need to quickly learn how to use jQuery

UI, or designers who wish to see how jQuery UI functions, behaves, and looks To get the most out of this book you should have a good working knowledge of HTML, CSS, and JavaScript, and should ideally be comfortable using jQuery

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[ 6 ]

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Introducing jQuery UI

Welcome to jQuery UI 1.8: The User Interface Library for jQuery This resource aims

to take you from your first steps to an advanced usage of the JavaScript library of

UI widgets and interaction helpers that are built on top of the hugely popular and easy-to-use jQuery

jQuery UI extends the underlying jQuery library to provide a suite of rich and interactive widgets along with code-saving interaction helpers, built to enhance the user interfaces of your websites and web applications It's the official UI library for jQuery and although it is not the only library built on top of jQuery, in my opinion

it is without a doubt the best

This chapter will cover the following topics:

• How to obtain a copy of the library

• How to set up a development environment

• The structure of the library

• ThemeRoller

• Browser support

• How the library is licensed

• The format of the API

Introducing jQuery UI

[ 8 ]

jQuery has quickly become one of the most popular JavaScript libraries in use

today jQuery UI will definitely become the extension library of choice, thanks to its ever-growing range of common UI widgets, high levels of configurability, and its exceptional ease of implementation

jQuery UI runs on top of jQuery so the syntax used to initialize, configure, and manipulate the different components is in the same comfortable, easy-to-use style

as jQuery We automatically get all of the great jQuery functionality at our disposal

as well The library is also supported by a range of incredibly useful tools, such as the CSS framework that provides a range of helper CSS classes, and the excellent ThemeRoller application that allows us to visually create our own custom themes for the widgets, or choose from a growing library of pre-existing themes

Over the course of this book, we'll look at each of the existing components that make

up the library We will also be looking at their configuration options and try out their methods in order to fully understand how they work and what they are capable of

By the end of the book, you'll be an expert in its configuration and use

We already have a basic working knowledge of the components when we add a new widget or interaction helper, because of the consistency in how we implement the different components that make up the library Therefore, we only need to learn any widget-specific functionality to master the particular component we wish to use

Downloading the library

To obtain a copy of the library, we should visit the download builder at

http://jqueryui.com/download This tool gives us a range of different options for building a download package that is tailored for our particular implementational requirements The following screenshot shows the download builder:

Chapter 1

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We can either download the complete current release of the library (version 1.8.9 at the time of writing), or a complete package of a legacy version We can also select just the components that we want and download a custom package

Introducing jQuery UI

[ 10 ]

This book is specifically tailored towards version 1.8, which

is above of jQuery UI and requires jQuery 1.3.2 or higher To support older versions of jQuery, the legacy version 1.7.3 is also available from the download builder

The page is laid out in a really friendly and easy-to-use way It lists all of the

different components in their respective groupings (core, interaction helpers, and widgets) and allows us to choose from one of 24 different predesigned themes (or no theme at all) The page also provides information about the package (including both its compressed and uncompressed size)

We'll look at the different files found within the library in just a moment, but for now we should download the complete library It will contain everything we need, including the JavaScript and CSS files, as well as any images from the current theme that different components rely on It even contains the latest version of jQuery itself,

so we don't need to worry about downloading this separately

For now, just use the Stable link at the top of the page This will give us the default theme, which is called smoothness We'll look at downloading and using other

themes in the next chapter

Hosted Files

We don't even need to download the library in order to implement it in

a production web application Both jQuery and jQuery UI are hosted on Google and Microsoft's Content Delivery Networks (CDN), so we

can include <script> elements that link to these files instead of using

local versions Only the complete library (not individual components) is available, although there are a range of different releases

On a live site that receives a lot of international traffic, using a CDN will help ensure that the library files are downloaded to a visitor's computer from a server that is geographically close to them This helps in making

the response quicker for them and saving our own bandwidth This is not recommended for local development however

Google's CDN can be found at: http://code.google.com/apis/

libraries/

Microsoft's CDN can be found at: http://www.asp.net/

ajaxlibrary/cdn.ashx

Chapter 1

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Setting up a development environment

We'll need a location to unpack the jQuery UI library in order to easily access the different parts of it within our own files We should first create a project folder, into which all of our example files, as well as all of the library and other associated resources, can be saved

Create a new directory in your C: drive, or in your home directory, and call it

jqueryui This will be the root folder of our project and will be the location where

we store all of the example files that we'll make over the course of the book

The structure of the accompanying code download for this book will mirror the local environment we are creating

To unpack the library, open it up in a compression program, such as the open source 7-zip, and choose the extract or unzip command When prompted for a location to unpack the archive to, choose the jqueryui folder that we just created

7-zip can be found at: http://www.7-zip.org/

The code examples that we'll be looking at use other resources, mostly images, but occasionally some PHP files too The accompanying code download available on Packt's website contains all of the images that we'll be using You should download this now if you can Visit: http://www.packtpub.com/support/book/user-

interface-library-for-jquery You'll need to create a new folder within the jqueryui project folder and call it img, then unpack all of the images within the img folder in the archive, to this new folder

The code download also contains all the examples files as well as the library itself These files are provided in the hope that they will be used for reference purposes only I'd urge you to follow the examples in the book as you go along, manually creating each file as it is shown, instead of just referring to the files in the code

download The best way to learn code is to code

This is all that we need to do, no additional platforms or applications need to

be installed and nothing needs to be configured or set up As long as you have

a browser and some kind of code or text editor, everything is in place to begin

developing with the library

Introducing jQuery UI

[ 12 ]

The structure of the library

Let's take a moment to look at the structure of the library once it has been unpacked,

so that we know where to look for specific utilities and files This will give us a feel for its composition and structure Open up the jqueryui folder where we unpacked the library The contents of this folder should be as follows:

The js folder contains minified versions of jQuery and the complete jQuery UI library, with all components rolled into one file In a live project, it is the js

and css folders that we'd want to drop into our site

The index is an HTML file that gives a brief introduction to the library and displays all of the widgets along with some of the CSS classes If this is the first time you've ever used the library, you can take a look at this file to see some of the things that we'll be working with throughout the course of this book

The development-bundle directory contains a series of resources to help us develop with the library It consists of the following subdirectories:

Chapter 1

[ 13 ]

The external folder contains a set of tools that may be of use to developers They are as follows:

• The bgiframe plugin

• The cookie plugin

• The unit testing suite qunit (consisting of a JavaScript and a CSS file)

• The simulate plugin

• The metadata plugin used to parse metadata from elements

The bgiframe plugin is used to fix the issue in IE6 where <select> elements appear above other content, regardless of z-index The cookie plugin makes it easy to use browser cookies qunit is jQuery's unit testing suite and can be used to run unit tests on widgets and plugins that we may create For more information on QUnit, visit http://docs.jquery.com/QUnit

The themes folder contains the default theme, or the theme that was selected during

in the download builder Other themes that we download at a later point or themes

we create ourselves, can also be stored here

The ui folder contains the individual and uncompressed source files of each of the different components of the library

ThemeRoller

ThemeRoller is a custom tool written with jQuery and PHP It allows us to visually produce our own custom jQuery UI theme and package it up in a convenient and downloadable archive, which we can drop into our project with no further coding (other than using the style sheet in an HTML <link> element of course)

ThemeRoller was created by Filament Group, Inc and makes use of a number

of jQuery plugins released into the open source community It can be found at http://ui.jquery.com/themeroller It is due to be updated shortly to coincide with the 1.9 release of jQuery UI

Introducing jQuery UI

[ 14 ]

ThemeRoller is certainly the most comprehensive tool available for creating your own jQuery UI themes We can very quickly and easily create an entire theme comprised of all of the styles needed for targeting the different widgets that

make up the library, including the images we'll need

If you looked at the index.html file a little earlier, then the ThemeRoller landing page will instantly be familiar, as it shows all of the UI widgets on the page, skinned

with the default smoothness theme.

The page features an interactive menu on the left that is used to work with the application Each item within the menu expands to give you access to the available style settings for each part of the widget, such as the content and the clickable areas: the header and content areas of the widget, and other associated things such as warnings and error messages

Chapter 1

[ 15 ]

Here we can create our custom theme with ease and see the changes instantly, as they are applied to the different visible parts of each widget on the page:

When you're not feeling particularly inspired while creating a theme, there is also

a gallery of pre-configured themes that you can instantly use to generate a fully configured theme Aside from convenience, the best thing about these pre-selected themes is that when you select one, it is loaded into the left menu Therefore, you can easily make little tweaks as required

This is an excellent way to create a visually appealing custom theme that matches the style of your existing site, and is the recommended method of creating custom skins

Introducing jQuery UI

[ 16 ]

Installing and using the new theme is as easy as selecting or creating it The

Download theme button in the above screenshot takes us back to the download

builder, which has the CSS and images for the new theme, integrated into the

download package

If it's just the new theme we want, we can deselect the actual components and just download the theme Once downloaded, the css folder within the downloaded archive will contain a folder that has the name of the theme We can simply drag this folder into our own local css folder, and then link to the style sheet from our pages

We won't be looking at this tool in much detail throughout the book We'll be

focusing instead on the style rules that we need to manually override in our own custom style sheets to generate the desired look of the examples manually

Component categories

There are three types of components found within the jQuery UI library:

1 Low-level interaction helpers: designed to work primarily with

mouse events

2 Widgets: produce visible objects on the page.

3 Core components: components that other parts of the library rely on.

The core components consist of:

to be used standalone, and exposes no functionality that can be used outside of another component

The interaction helpers are comprised of the following components:

Apart from these components and interaction-helpers, there are also a series of UI effects that produce different animations or transitions on targeted elements on the page These are excellent for adding flair and style to our pages We'll be looking at these effects in the final chapter of the book.

The great thing about jQuery UI's simplified API is that once you have learned to use all of the existing components (as this book will show you), you'll be able to pick up any new components very quickly As this book is being written, there are already a number of new components nearing release, with many more in the pipeline, and all

of these components will automatically be ThemeRoller-ready

Browser support

Like jQuery itself, jQuery UI supports all of the major browsers in use today,

including the following:

• IE6, IE7, IE8, and IE9

• Firefox 2, Firefox 3, and Firefox 4, and Firefox 5

• Opera 9, Opera 10, and Opera 11

• Safari 3, Safari 4, and Safari 5

In practice, it is advisable to keep your code as minimal as possible (which jQuery can really help with anyway) But to make the examples more readable and

understandable, we'll be separating as much of the code as possible into discrete modules Therefore, callback functions and configuration objects will be defined separately from the code that calls or uses them

To reduce the number of files that we have to create and work with, all of the

JavaScript will go into the host HTML page on which it runs, as opposed to

in separate files Please keep in mind that this is not advisable for production

websites When scripts reside within external js files, the browser is able to cache them for vastly improved loading speeds When scripts are in the <body> element

of a page, the browser cannot store them in the cache

I'd also just like to make it clear that the main aim throughout the course of this book is to learn how to use the different components that make up jQuery UI If an example seems a little convoluted, it may simply be that this is the easiest way to expose the functionality of a particular method or property, as opposed to a situation that we would find ourselves coding for in regular implementations

I'd like to add here that the jQuery UI library is currently undergoing a rapid period

of expansion and development It is also constantly growing and evolving, with bug fixes and feature enhancements continually being added It would be impossible to keep entirely up-to-date with this aggressive expansion and cover components that are literally about to be released

Chapter 1

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The MIT license explicitly states that users of the software (jQuery UI in this case) are free to use, copy, merge, modify, publish, distribute, sublicense, and sell This lets us do pretty much whatever we want with the library The only requirement imposed by this license is that we must keep the original copyright and warranty statements intact

This is an important point to make You can take the library and do whatever you like with it Build applications on top of the library and then sell those applications,

or give them away for free Put the library in embedded systems like cell phone OS and sell those But whatever you do, leave the original text file with John Resig's name present in it You may also duplicate it word-for-word in the help files or documentation of your application

The MIT license is very lenient, but because it is not copyrighted itself, we are free to change it We could therefore demand that users of our software give attribution

to us instead of the jQuery team, or pass off the code as our own

The GPL license is copyrighted, and offers an additional layer of protection for the library's creators and the users of our software jQuery is provided for free and is open source The GPL license ensures that it will always remain that way, regardless

of the environment it may end up in, and that the original creators of the library are given the credit they deserve Again, the original GPL license file must be available

in some form, within your application or site

The licenses are not there to restrict us in any way, and are not the same as the kind

of license that comes with software you might purchase and install on your own computer In most cases, how the library is licensed will not be a consideration when using it Plugin authors, however, will want to ensure that their plugins are released under a similar license

Introducing jQuery UI

[ 20 ]

The API for each component consists of a series of different methods While these are all technically methods, it may be useful to categorize them based on their particular function

Method type Description

The plugin method This method is used to initialize the component and

is simply the name of the component, followed by parentheses I will refer to this throughout the book as the plugin method or widget method

Shared API methods The destroy method can be used with any of the

components, to completely disable the widget being used and in most cases, returns the underlying HTML to its original state

The option method is used by all components to get or set any configuration option after initialization

The enable and disable methods are used by most library components to enable or disable the component

The widget method, exposed by all widgets, returns a reference to the current widget

Specialized methods Each component has one or more methods unique to that

particular component that perform specialized functions

Methods are consistently called throughout each of the different components by passing the method that we'd like to call, as a simple string to the component's plugin method, with any arguments that the method accepts passed as strings after the method name

For example, to call the destroy method of the accordion component, we would simply do the following:

$("#someElement").accordion("destroy");

See how easy that was? Every single method exposed by all of the different

components, is called in this same simple way

Some methods, like standard JavaScript functions, accept arguments that trigger different behavior in the component If we wanted to call the disable method on a particular tab in the tabs widget for example, we would do the following:

$("#someElement").tabs("disable", 1);

To use the option method in getter mode to retrieve the current value of an option,

we could use the following code:

$("#someElement").accordion("option", "navigation", true);

This code would set the value of the navigation option to true Note that, an object literal can also be passed to the option method in order to set several different options at once, for example:

$("#someElement").accordion("option", {

navigation: true,

autoHeight: false

});

As you can see, although the option method gives us the power to both get

and set configuration options, it still retains the same easy-to-use format of the other methods

Using jQuery UI feels just like using jQuery and having built up confidence coding with jQuery, moving on to jQuery UI is the next logical step to take