WordPress 3.0 jQuery

Table of Contents

Wordpress 3.0 jQuery

Credits

About the Author

About the Reviewer

Preface

What this book covers

What you need for this book

Who this book is for

Conventions

Reader feedback

Customer support

Errata

Piracy

Questions

1. Getting Started: WordPress and jQuery

This book's approach

Core fundamentals you need to know

WordPress

Basic programming

JavaScript and AJAX techniques

PHP

Essential tools

Code/HTML editor

Firefox

Web Developer toolbar

Firebug

Not essential, but helpful: Image editor

jQuery background and essentials

What jQuery does (really well)

How we got here: From JavaScript to jQuery

Once upon a time, there was JavaScript

Why jQuery is simpler than JavaScript

Understanding the jQuery wrapper

Getting started with jQuery

Downloading from the jQuery site

Including the jQuery library

WordPress background and essentials

Overview of WordPress

Essentials for getting WordPress running

Using WAMP

Using MAMP

Choosing a hosting provider

Rolling out WordPress

jQuery and WordPress: Putting it all together

Summary

2. Working with jQuery in WordPress

Getting jQuery into WordPress

jQuery now comes bundled with WordPress

Registering jQuery in a WP theme

Avoiding problems registering jQuery

Using Google's CDN

Registering and including jQuery through Google's CDN into a theme

Understanding Google's versioning system

Using WordPress' bundled jQuery versus including your own jQuery download or using Google's CDN

Keeping conflicts out!

Setting your own jQuery variable

But I really want to use the $ variable!

Launching a jQuery script

Our first WordPress and jQuery setup

Registering jQuery in our setup

Registering your own custom script file

Setting up the custom-jquery file

jQuery secret weapon #1: Using selectors and filters

Selecting anything you want from the document

Filtering those selections

Basic filters

Child filters

Content filters

Form filters

Attribute filters

Visibility

jQuery secret weapon #2: Manipulating CSS and elements in the DOM

Manipulating CSS

Manipulating attributes

Manipulating elements and content

Working with the DOM

jQuery secret weapon #3: Events and effects (aka: the icing on the cake)

Working with events

Helpers are so helpful!

Working with bind, unbind, and the event object

Adding effects

Showing and hiding

Sliding in and out

Fading in and out

Working with the animate function

Making it all easy with statement chaining

Our First Project: Expanding/collapsing WordPress posts

Keeping jQuery readable

Summary

3. Digging Deeper: Understanding jQuery and WordPress Together

Two ways to plugin jQuery into a WordPress site

WordPress themes overview

WordPress plugins overview

jQuery plugins overview

The basics of a WordPress theme

Understanding the template's hierarchy

A whole new theme

The Loop

Tags and hooks

Conditional tags

Template include tags

Creating custom header, footer, sidebar includes

Plugin hooks

Project: Editing the main loop and sidebar in the default theme

Changing the loop

Changing the sidebar

The basics of a WordPress plugin

Project: Writing a WordPress plugin to display author bios

Coding the plugin

Activating our plugin in WordPress

The basics of a jQuery plugin

Project: jQuery fade in a child div plugin

Extra credit: Adding your new jQuery plugin to your WordPress plugin

Putting it all together: Edit the theme or create a custom plugin?

Summary

4. Doing a Lot More with Less: Making Use of Plugins for Both jQuery and WordPress

The project overview: Seamless event registration

What the client wants

Part 1: Getting everything set up

What we'll need

ColorBox

Cforms II

Installing the WordPress plugin

Setting up the registration form with cforms II

Striking a balance: Forms should be short and easy and yet retrieve useful information

Creating the register page using WordPress 3.0's custom menu option

Working with WordPress 3.0's custom menu option

Customizing the theme

Creating the custom page template

Creating the custom category template

Getting jQuery in on the game plan

Including the ColorBox plugin

Writing a custom jQuery script

Pulling it all together: One tiny cforms II hack required

Part 2: Form validation—make sure that what's submitted is right

The trick to client-side validation: Don't just tell them when it's wrong!

Blank input validation

Properly formatted e-mail validation

Final thoughts and project wrap up: It's all about graceful degrading

Summary

5. jQuery Animation within WordPress

jQuery animation basics

CSS properties made magical

Making it colorful

Taking it easy, with easing control

Timing is everything: Ordering, delaying, and controlling the animation que

Getting your ducks in row: Chain 'em up

Delay that order!

Jumping the queue

Stepping to completion

Grabbing the user's attention

Project: Animating an alert sticky post

Creating easy, animated graphs

Delving deeper into animation

Project: Creating snazzy navigation

Project: Creating rotating sticky posts

Putting in a little extra effort: Adding a loop indicator

Summary

6. WordPress and jQuery's UI

Getting to know jQuery's UI plugin

Widgets

Interactions

Effects

jQuery UI plugin versions bundled in WordPress

Picking and choosing from the jQuery's UI site

Making it look right: Easy UI theming

Including the jQuery UI plugin features into your WordPress site

Including jQuery's UI from WordPress' bundle

Including from the Google CDN

Loading up your own custom download from your theme or plugin directory

Don't forget your styles!

Enhancing effects with jQuery UI

Effects made easy

Easing is just as easy

Color animation with jQuery UI

Enhancing the user interface of your WordPress site

Project: Turning posts into tabs

Setting up custom loops in the WordPress theme

Implementing tabs entirely with jQuery

Project: Accordion-izing the sidebar

Project: Adding a dialog box to a download button with icons

Summary

7. AJAX with jQuery and WordPress

What AJAX is and isn't: A quick primer

AJAX: It's better with jQuery

Assessing if AJAX is right for your site—a shorter disclaimer

Getting started with jQuery's AJAX functionality

Using the .ajax() function

Taking shortcuts

Specifying where to .load() it

Transforming loaded content

Project: Ajaxifying posts

.getJSON: The littlest birds get the most re-tweets

JSON and jQuery basics

What JSON looks like

Using JSON in jQuery

Using .getJSON with Twitter

Using Twitter's user timeline method

What's Twitter sending back?

Using getJSON with Flickr

Other popular services that offer APIs with JSON format

Project: Ajax-izing the built-in comment form

Summary

8. Tips and Tricks for Working with jQuery and WordPress

Keep a code arsenal

Free your arsenal

Your arsenal on-the-go

jQuery tips and tricks for working in WordPress

Try to use the latest version of jQuery

Stay current with the Google CDN

Stay in No Conflict mode

Make sure other scripts in the theme or plugin use the Script API

Check your jQuery syntax

Colons and semicolons

Closing parenthesis

Mismatched double and single quotes

Use Firefox and Firebug to help with debugging

Know what jQuery is doing to the DOM

Web Developer's Toolkit: View Generated Source

Seeing what Firebug sees

Tips for writing great selectors

Don't forget about your selection filters!

Keep the WordPress editor's workflow flowing

But my jQ script or plugin needs to have specific elements!

WordPress tips and tricks for optimal jQuery enhancements

Always use wp_enqueue_script to load up jQuery and wp_register_script for plugins for custom scripts.

Always start with a basic, working, plain HTML WordPress site

Validate, validate, validate!

Check your PHP syntax

PHP shorthand

Check for proper semicolons

Concatenations

Summary

A. Appendix: jQuery and WordPress Reference Guide

jQuery reference for WordPress

noConflict mode syntax

Useful selector filters for working within WordPress

Selection filter syntax

Selector filters

Content filter syntax

Content filters

Child filter syntax

Child filters

Form filter syntax

Form filters

jQuery: Useful functions for working within WordPress

Working with classes and attributes

Traversing the DOM

Important jQuery events

Animation at its finest

Getting the most out of WordPress

The WordPress template hierarchy

Top WordPress template tags

Conditional tags

Quick overview of loop functions

Setting up WordPress shortcodes

Creating a basic shortcode

Summary

Index

Wordpress 3.0 jQuery

Wordpress 3.0 jQuery

Copyright © 2010 Packt Publishing

All rights reserved. No part of this book may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, without the prior written permission of the publisher, except in the case of brief quotations embedded in critical articles or reviews.

Every effort has been made in the preparation of this book to ensure the accuracy of the information presented. However, the information contained in this book is sold without warranty, either express or implied. Neither the author, nor Packt Publishing, and its dealers and distributors will be held liable for any damages caused or alleged to be caused directly or indirectly by this book.

Packt Publishing has endeavored to provide trademark information about all of the companies and products mentioned in this book by the appropriate use of capitals. However, Packt Publishing cannot guarantee the accuracy of this information.

First published: September 2010

Production Reference: 1170910

Published by Packt Publishing Ltd.

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Birmingham, B27 6PA, UK.

ISBN 978-1-849511-74-2

www.packtpub.com

Cover Image by Jose Argudo (<jose@joseargudo.com>)

Credits

Author

Tessa Blakeley Silver

Reviewer

Chris Gossmann

Acquisition Editor

Chaitanya Apte

Development Editor

Ved Prakash Jha

Technical Editors

Aaron Rosario

Mohd. Sahil

Copy Editors

Janki Mathuria

Laxmi Subramanian

Indexer

Rekha Nair

Editorial Team Leader

Akshara Aware

Project Team Leader

Priya Mukherji

Project Coordinator

Vincila Colaco

Proofreader

Aaron Nash

Graphics

Nilesh R. Mohite

Geetanjali Sawant

Production Coordinator

Aparna Bhagat

Cover Work

Aparna Bhagat

About the Author

Tessa Blakeley Silver has prior experience in print design and traditional illustration. She evolved over the years into web and multi-media development, where she focuses on usability and interface design.

Prior to starting her consulting and development company hyper3media (pronounced hyper-cube media) http://hyper3media.com, Tessa was the VP of Interactive Technologies at eHigherEducation, an online learning and technology company developing compelling multimedia simulations, interactions, and games which met online educational requirements like 508, AICC and SCORM. She has also worked as a consultant and freelancer for J. Walter Thompson and the Diamond Trading Company (formerly known as DeBeers) and was a Design Specialist and Senior Associate for PricewaterhouseCoopers' East Region Marketing department.

Tessa has authored a few books for Packt Publishing, including WordPress 2.8 Theme Design and Joomla 1.5 Template Design.

I send a huge thank you to the Packt team who have made this title possible and whose help in getting it out into the world has been invaluable. Special thanks to Chaitanya and Thorsten for their editing work. Additional big-time thank you goes out to Vincila for the backbreaking work and diligence it takes to keep to a schedule.

I'd also like to thank the exemplary WordPress and jQuery community (Matt and John, you guys Rock) and all who participate and power the Open Source world and strive to improve the accessibility of the Web for all.

Additional thanks goes out to my very patient partner and our little daughter (who's not so patient) who per usual, spent quite a few evenings without me while I worked on this title. I love you both and appreciate your flexibility with me while I work on interesting books and projects (yes, I'm working on getting better at estimating how much time it really, really takes to write a chapter).

About the Reviewer

Chris Gossmann is Lead Developer and co-owner of the well-known Thematic, an open-source WordPress Theme Framework. Chris has over four years experience with WordPress. Today he is constantly enhancing Thematic. As the co-worker of Milo, one of the best web designers, Chris Gossmann creates highly customized WordPress and BuddyPress solutions for international customers.

Preface

This easy-to-use guide will walk you through the ins and outs of creating sophisticated professional enhancements and features, specially tailored to take advantage of the WordPress personal publishing platform. It will walk you through clear, step-by-step instructions to build several custom jQuery solutions for various types of hypothetical clients and also show you how to create a jQuery and Wordpress plugin.

What this book covers

Chapter 1, Getting Started: WordPress and jQuery...This chapter introduces the reader to the core fundamentals that they need to be familiar with in order to get the most out of the book. HTML, CSS, PHP, and JavaScript syntax, and how to recognize the various parts of those syntaxes are covered, as well as a list of tools of the trade which covers what features their code editor, browser, and even image editor should have. The chapter also illustrates exactly how CSS, JavaScript, and jQuery work in the browser with the HTML served up from the WordPress site.

Chapter 2, Working with jQuery in WordPress...This chapter goes into the details of how to start working with jQuery specifically within WordPress. It covers how to properly include jQuery using the Script API and focuses on jQuery's selectors (very important for working in WordPress) as well as jQuery's top functions.

Chapter 3, Digging Deeper: Understanding jQuery and WordPress Together...This chapter takes the reader to a deeper level and introduces them to all the ways that jQuery can be applied to a WordPress site: Through a custom script in the WordPress theme, as a jQuery plugin called in through the theme, and lastly, as a custom jQuery script or plugin applied to a WordPress plugin! The ways to affect a WordPress site with jQuery are numerous, and the pros and cons of each method is considered so that the reader can assess their own projects accurately. The chapter also introduces the reader to their first hypothetical client and covers how to create their own jQuery plugin and then wrap that jQuery plugin into a WordPress plugin so that a site administrator could easily implement the enhancement without having to know how to edit the theme.

Chapter 4, Doing a Lot More with Less: Making Use of Plugins for Both jQuery and WordPress...You thought you learned quite a bit in Chapter 3? Hang on to your mouse. You're about to embark on a nice little project that requires you getting familiar with the popular jQuery plugin Colorbox, as well as the popular WordPress plugin Cforms II and mashing the two with your own custom jQuery magic to whip up some slick event registration that will knock a client's socks off.

Chapter 5, jQuery Animation within WordPress...If you're going to use jQuery, you might as well really use it to its fullest, which means animation. This chapter covers using jQuery's animation functions and shortcuts to create some sharp, well timed visual enhancements that grab the site user's attention as well as create a super slick navigation enhancement and an awesome rotating slideshow of sticky posts.

Chapter 6, WordPress and jQuery's UI...Now that we have some animation chops under our belt, we can make that work even easier by using jQuery's UI plugin which includes the Easing and Color plugins we learned about in Chapter 5. In this chapter, we're going to also take advantage of the UI plugin's widgets and events features to create some super useful interfaces in our WordPress site.

Chapter 7, AJAX with jQuery and WordPress...This chapter introduces you to what AJAX is and isn't along with the top ways to get started using AJAX techniques in your WordPress site; you'll load in HTML from other pages on your site, get your tweets and favorite flickr pictures pulled in through JSON, and last but not least, custom AJAXing the built in WordPress comment form.

Chapter 8, Tips and Tricks for Working with jQuery and WordPress...This chapter covers the top tips and tricks for getting the most out of jQuery specifically within WordPress. Most of these best practices are covered throughout the title but in this chapter we take a look at exactly why they're so important, espeically within the context of WordPress and how to implement them.

Appendix A, jQuery and WordPress Reference Guide...Dog-ear this appendix and consider it your cheat sheet. Once you work your way through the book, why waste time hunting and pecking your way back through it to recall some function's bit of syntax and what its parameters are? This book extracts the most important information about jQuery and WordPress and breaks it down into an easy-to-skim reference guide so that you can easily find the syntax for most jQuery selectors, remind yourself of the top jQuery functions that you'll need for most WordPress development and their parameters, as well as helpful WordPress template tags and API functions and other useful WordPress know-how such as structuring the Loop and the Theme Template Hierarchy.

What you need for this book

WordPress (2.9.2 or 3.0)

The jQuery library (1.4.2)

A web server (local WAMP or MAMP installation or hosted by a provider)

A web browser (Firefox or better)

A good code or HTML editor

Who this book is for

This book is for anyone who is interested in using jQuery with a WordPress site. It's assumed that most readers will be WordPress developers with a pretty good understanding of PHP or JavaScript programming and at the very least, experience with HTML/CSS development who want to learn how to quickly apply jQuery to their WordPress projects.

Conventions

In this book, you will find a number of styles of text that distinguish between different kinds of information. Here are some examples of these styles, and an explanation of their meaning.

Code words in text are shown as follows: We can include other contexts through the use of the include directive.

A block of code is set as follows:

jQuery(document).ready(function(){

jQuery(p).css(background-color, #ff6600);

});

When we wish to draw your attention to a particular part of a code block, the relevant lines or items are set in bold:

jQuery

(document).ready(function()

{

jQuery

(p).css(background-color, #ff6600);

});

For for clarity and conciseness, many code examples in this title are extracted. An extracted block of code is set as follows:

...

jQuery(p).css(background-color, #ff6600);

}

...

Code and markup preceded and ended with ellipses ... are extracted from the full context of code and/or a larger body of code and markup. Please refer to the downloadable code bundle to see the entire work.

New terms and important words are shown in bold. Words that you see on the screen, in menus or dialog boxes for example, appear in the text like this: clicking the Next button moves you to the next screen.

Note

Warnings or important notes appear in a box like this.

Note

Tips and tricks appear like this.

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Tip

Downloading the example code for this book

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Errata

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Questions

You can contact us at <questions@packtpub.com> if you are having a problem with any aspect of the book, and we will do our best to address it.

Chapter 1. Getting Started: WordPress and jQuery

Welcome to WordPress and jQuery. The WordPress web-based publishing platform and jQuery's JavaScript library are two of the most powerful tools used on the Web today. Combining these tools together doubles the power and flexibility of your websites. Both technologies, being easy and fun to