Using the book examples

The library is as flexible as standard JavaScript. By this, I mean that there is often more than one way of doing the same thing, or achieving the same end. For example, the callback events used in the configuration objects for different components can usually take either references to functions or inline anonymous functions, and use them with equal ease and efficiency.

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 options will be defined separately from the code that calls or uses them.

Throughout this book, we will separate JavaScript and CSS code into separate files; while this is overkill for the purposes of development work, it is advisable for production websites. Scripts that reside in external js files can be cached by the browser for vastly improved loading speeds; those written in-line (that is, directly into a <script> tags) are not cached by the browser.

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 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 regular implementations.

I'd like to add here that the jQuery UI library is currently going through a rapid period of expansion, bug-fixing, and development. For this release, the jQuery team is focusing on bug-fixing to help make the library as stable as possible. Over the longer term, the jQuery UI team is focusing on complete redesigns of each widget's API, ahead of adding a host of new widgets in future releases, and completing a planned merger with jQuery Mobile.