Book Image

WordPress Plugin Development Cookbook - Third Edition

By : Yannick Lefebvre
Book Image

WordPress Plugin Development Cookbook - Third Edition

By: Yannick Lefebvre

Overview of this book

WordPress is one of the most widely used, powerful, and open content management systems (CMSs). Whether you're a site owner trying to find the right extension, a developer who wants to contribute to the community, or a website developer working to fulfill a client's needs, learning how to extend WordPress' capabilities will help you to unleash its full potential. This book will help you become familiar with API functions to create secure plugins with easy-to-use administration interfaces. This third edition contains new recipes and up-to-date code samples, including new chapters on creating custom blocks for the block editor and integrating data from external sources. From one chapter to the next, you’ll learn how to create plugins of varying complexity, ranging from a few lines of code to complex extensions that provide intricate new capabilities. You'll start by using the basic mechanisms provided in WordPress to create plugins, followed by recipes covering how to design administration panels, enhance the post editor with custom fields, store custom data, and even create custom blocks. You'll safely incorporate dynamic elements into web pages using scripting languages, learn how to integrate data from external sources, and build new widgets that users will be able to add to WordPress sidebars and widget areas. By the end of this book, you will be able to create WordPress plugins to perform any task you can imagine.
Table of Contents (15 chapters)

Chapter 9: Leveraging JavaScript, jQuery, and AJAX Scripts

JavaScript libraries, especially the very popular jQuery library along with its numerous plugins, can do wonders in bringing a website to life with slick animations, dynamic data queries, and advanced graphical features. Unfortunately, for all of their benefits, these scripts can also be difficult to work with. For example, loading more than one copy of jQuery can destroy everything that was set up by another instance, and errors in one script usually prevent other scripts from running correctly.

WordPress' answer to this convoluted architecture is twofold. As a first step, it comes pre-packaged with a copy of jQuery and many other popular JavaScript libraries that plugin developers can use without having to load their own versions. Then, to prevent multiple copies from being loaded on a page, it offers easy-to-use functions that queue up scripts and styles to identify duplicates before rendering pages.

This chapter...