Book Image

Learning jQuery, Third Edition

Book Image

Learning jQuery, Third Edition

Overview of this book

To build interesting, interactive sites, developers are turning to JavaScript libraries such as jQuery to automate common tasks and simplify complicated ones. Because many web developers have more experience with HTML and CSS than with JavaScript, the library's design lends itself to a quick start for designers with little programming experience. Experienced programmers will also be aided by its conceptual consistency.Learning jQuery Third Edition is revised and updated for version 1.6 of jQuery. You will learn the basics of jQuery for adding interactions and animations to your pages. Even if previous attempts at writing JavaScript have left you baffled, this book will guide you past the pitfalls associated with AJAX, events, effects, and advanced JavaScript language features.Starting with an introduction to jQuery, you will first be shown how to write a functioning jQuery program in just three lines of code. Learn how to add impact to your actions through a set of simple visual effects and to create, copy, reassemble, and embellish content using jQuery's DOM modification methods. The book will step you through many detailed, real-world examples, and even equip you to extend the jQuery library itself with your own plug-ins.
Table of Contents (24 chapters)
Learning jQuery Third Edition
Credits
Foreword
About the Authors
About the Reviewers
www.PacktPub.com
Preface
Index

Observing and interrupting animations


Our basic animation already reveals a problem. As long as the user is careful about drawing the mouse over and out of the images slowly and avoiding triggering repeated mouseenter and mouseleave events too quickly, the animations proceed as intended. When the events are triggered quickly and repeatedly, however, we see that the images also grow and shrink repeatedly, well after the last event is triggered. This occurs because, as discussed in Chapter 4, animations on a given element are added to a queue and called in order. The first animation is called immediately, completes in the allotted time, and then is shifted off the queue. At this point, the next animation becomes first in line, is called, completes, is shifted, and so on until the queue is empty.

There are many cases in which this animation queue, known within jQuery as fx, is desirable. In the case of hover actions such as ours, though, it needs to be circumvented.

Determining the animation...