Book Image

Learning jQuery - Fourth Edition

By : Karl Swedberg, Jonathan Chaffer
Book Image

Learning jQuery - Fourth Edition

By: Karl Swedberg, Jonathan Chaffer

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. LearningjQuery - Fourth Edition is revised and updated version 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 take 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 Fourth Edition
About the Authors
About the Reviewers

Removing an event handler

There are times when we will be done with an event handler we previously registered. Perhaps the state of the page has changed such that the action no longer makes sense. It is typically possible to handle this situation with conditional statements inside our event handlers, but it may be more elegant to unbind the handler entirely.

Suppose that we want our collapsible style switcher to remain expanded whenever the page is not using the normal style. While the Narrow Column or Large Print button is selected, clicking on the background of the style switcher should do nothing. We can accomplish this by calling the the .off() method to remove the collapsing handler when one of the non-default style switcher buttons is clicked:

$(document).ready(function() {
  $('#switcher').click(function(event) {
    if (!$('button')) {
      $('#switcher button').toggleClass('hidden');
  $('#switcher-narrow, #switcher-large').click(function() {