Build your own Plugin

SpeakerAlexandre Marreiros

Tech Trainner and Speaker and Consultnat as Independent

CTO Innovagency

Contacts@alexmarreiros | amarreiros@gmail.com digitalmindignition.com

Build your own WordPress Plugin

Plugin“Plug-ins are a great way to enhance the functionality of your blog or WebSite by adding in extra features. These can be placed anywhere inside your template by function hooks. Over time the extensibility of WordPress’ plug-in system has allow tremendous growth and hundreds of developer-submitted pieces of software.”

Build your own WordPress Plugin

What i need to build plugin’sKnowledge of PHP (Rudimentar)

Basic understanding of the WordPress file structure

Good Ideias or problems

Build your own WordPress Plugin

Why Build Plugin’sWhen you need to solve a recorrent WordPress development need

When you need to extende the plataform

To a better understaning of the WordPress Backend

Build your own WordPress Plugin

Where Plugin’s Live?

Build your own WordPress Plugin

Best Pratice 1Give a “Home” to your Plugin this way you simplify Plugin file system struture

Create a readme.txt file to explain who are the person who knows how the Plugin is built

Build your own WordPress Plugin

To Start Create the base PHP file for your Plugin

You must start with the plugin declaration

Build your own WordPress Plugin

2 Build Aproaches Create an entire class system to avoid collisions with functions and variable names that already exist.

just write your code in sample functions.

Build your own WordPress Plugin

Best Pratice 2Don’t do Suicide if your plugin is simple don’t start building a entire new class ecosystem for him.

Build your own WordPress Plugin

Best Pratice 3

To avoid duplication use prefixing labels to all your variables and function names.

Build your own WordPress Plugin

Actions and Filters“Actions and Filters allow for plug-in developers to update bits of code throughout the WordPress admin panel pertaining to your new plug-in. This means you could add a new tab in the sidebar or additional settings links for your Plug-in options.”

Build your own WordPress Plugin

FilterA filter is used on data being passed into

WordPress. With filters you are quite literally able to filter content through your own custom written functions to change data in any way.

Used in cases like writing a sidebar widgets or smaller functions to change how a post should be displayed.

Build your own WordPress Plugin

ActionsTarget pre-defined areas in your templates and admin panel. Is important if your Plugin intend to be triggered when something happens in your WordPress event Pipeline.

Build your own WordPress Plugin

publish_post – called when a post is published or when status is changed into “published”save_post – called when a post/page is created from start or updatedwp_head – called when the template is loaded and runs the wp_head() functionloop_end – called immediately after the final post has been processed through the WordPress looptrackback_post – called whenever a new trackback is added into a post

Plugin Registering

Build your own WordPress Plugin

Plugin is installed

Plugin Creates his Hooks in

WP

Register functions as a Action Listener

Register functions as a Filter Listen

Plugin is “hooked” to WordPress

When Plugin is Called

Build your own WordPress Plugin

Wordpress executes an

action or render s

Wordpress Validates all the

register functions

If any

Call Plugins functions

(considering registering order)

Best Pratice 4

Be carefull not to destruct what plugin’s that came before you had made.

Build your own WordPress Plugin

Demo

Build your own WordPress Plugin

Let’s Play

Questions

http://codex.wordpress.org/Writing_a_PluginProfessional WordPress Plugin Development

 by Brad Williams, Ozh Richard and Justin TadlockWordPress 3 Plugin Development Essentials by

B Bondari and E Griffiths (24 Mar 2011)

Resources

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Build your own WordPress Plugin

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