Joomla Programming

Joomla!™

Programming

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Joomla!™

Programming

Mark Dexter

Louis Landry

Upper Saddle River, NJ • Boston • Indianapolis • San Francisco

New York • Toronto • Montreal • London • Munich • Paris • Madrid

Capetown • Sydney • Tokyo • Singapore • Mexico City

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Many of the designations used by manufacturers and sellers to distinguish their products

are claimed as trademarks. Where those designations appear in this book, and the pub￾lisher was aware of a trademark claim, the designations have been printed with initial cap￾ital letters or in all capitals.

The authors and publisher have taken care in the preparation of this book, but make no

expressed or implied warranty of any kind and assume no responsibility for errors or omis￾sions. No liability is assumed for incidental or consequential damages in connection with

or arising out of the use of the information or programs contained herein.

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Library of Congress Cataloging- in- Publication Data

Dexter, Mark, 1954–

Joomla! programming / Mark Dexter, Louis Landry.

p. cm.

Includes index.

ISBN 978-0-13-278081-0 (pbk. : alk. paper) 1. Joomla! (Computer

file) 2. Web sites—Authoring programs. 3. Web site development. I.

Landry, Louis, 1980- II. Title.

TK5105.8885.J86D492 2012

006.7'6—dc23 2011052204

Copyright © 2012 Pearson Education, Inc.

All rights reserved. Printed in the United States of America. This publication is protected

by copyright, and permission must be obtained from the publisher prior to any prohibited

reproduction, storage in a retrieval system, or transmission in any form or by any means,

electronic, mechanical, photocopying, recording, or likewise. To obtain permission to use

material from this work, please submit a written request to Pearson Education, Inc., Per￾missions Department, One Lake Street, Upper Saddle River, New Jersey 07458, or you

may fax your request to (201) 236- 3290.

ISBN- 13: 978- 0- 13- 278081- 0

ISBN- 10: 0- 13- 278081- X

Text printed in the United States on recycled paper at at RR Donnelly in Crawfordsville,

Indiana.

First printing, March 2012

Editor- in- Chief

Mark L. Taub

Executive Editor

Debra Williams

Cauley

Development Editor

Sheri Cain

Managing Editor

John Fuller

Full- Service

Production Manager

Julie B. Nahil

Copy Editor

Scribe Inc.

Indexer

Scribe Inc.

Proofreader

Scribe Inc.

Technical Reviewer

Andrea Tarr

Publishing

Coordinator

Kim Boedigheimer

Compositor

Scribe Inc.

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This book is dedicated to the many hardworking volunteers

in the Joomla! community whose cheerful dedication renews

on a daily basis the authors’ faith in humankind.

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Contents

Preface xix

Acknowledgments xxvii

About the Authors xxix

1 What Is Joomla! Development? 1

Developing for Joomla Is Not Difficult! 1

The Joomla Technical Environment 1

Joomla Programming:

What Do You Need to Know? 3

Extending Joomla: Let Me Count the Ways 4

Open Source Means You Have Control 4

Overrides Let You Change What Shows on

the Page 4

Extensions 6

Plugins 6

Modules 9

Components 10

Languages 11

Templates 13

Which Extension Type

Should I Use for My Project? 14

Using Joomla as a Platform or Framework 15

Summary 16

2 Getting Your Workstation Ready for Joomla!

Development 17

Requirements to Run Joomla 17

Apache DocumentRoot Folder 18

Getting Up- To- Date Instructions 19

Windows Platforms 19

Mac OS X Plaform 19

Linux Platforms 20

Default Owner for Files and Folders 20

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viii Contents

Tools of the Trade 21

IDE versus Text Editor 21

Open- Source IDE Choices 22

Commercial IDEs 37

Text Editor Choices 37

Other Tools 38

Version Control Software 38

Automatic Builder Software (Ant and Phing) 38

Automated Test Programs 39

Summary 39

3 How Joomla! Works 41

Tour of Joomla Folders 41

Front End versus Back End 42

Cache 42

CLI 43

Components 43

Images 45

Includes 46

Installation 46

Language 47

Libraries 47

Logs 47

Media 47

Modules 48

Plugins 48

Templates 49

Tmp 50

Administrator 50

Joomla Platform 56

Web Programming versus “Normal” Programming 58

Maintaining the State of the Program 58

Controlling and Checking the Commands 60

Anatomy of a Joomla Execution Cycle 61

Load the Index.php File 62

Check the Execution Environment 62

Define the File Locations 64

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