Book Image

jQuery UI 1.7: The User Interface Library for jQuery

Book Image

jQuery UI 1.7: The User Interface Library for jQuery

Overview of this book

Modern web application user interface design requires rapid development and proven results. jQuery UI, a trusted suite of official plug-ins for the jQuery JavaScript library, gives you a solid platform on which to build rich and engaging interfaces with maximum compatibility and stability, and minimum 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 1.7 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.
Table of Contents (19 chapters)
jQuery UI 1.7
Credits
About the Author
About the Reviewers
Preface
Index

Draggable event callbacks


In addition to the options that we have already looked at, there are three more that can be used as callback functions to execute code after specific custom events, defined by the draggables component, occur. These events are listed below.

Option

Triggered

drag

When the mouse is moved while dragging.

start

When dragging starts.

stop

When dragging stops.

When defining callback functions to make use of these events, the functions will always receive two arguments automatically. The original event object as the first argument and a second object containing the following properties:

Option

Usage

helper

A jQuery object representing the helper element.

position

A nested object with properties top and left of the helper element relative to the original drag element.

absolutePosition

A nested object with properties top and left of the helper element relative to the page.

Using the callbacks, and the two objects that are passed as arguments, is extremely easy...