Getting Started with WordPress Development

WordPress is an incredibly powerful platform and framework for development, but until you learn how to use it you won't be able to make full use of its flexibility. In this session you will learn the core principles of WordPress development that will enable you to start taking full advantage of everything that it offers.

This presentation is aimed at experienced PHP developers who have minimal experience with WordPress development. It was presented at the Cape Town PHP Meetup on 23 April 2015: http://www.meetup.com/Cape-Town-PHP-Group/events/221748419/

The full video of the presentation is available here: https://www.youtube.com/watch?v=JbEgsygOxKU

Transcript

1. Getting Started With
   WordPress Development
   

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2. HTML PHP MVC WP
   

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5. Folder Structure
   Headers
   Events
   Plugin Development
   

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6. wp-content/plugins/plugin-slug
   plugin-slug.php
   readme.txt
   Folder Structure
   

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7. Headers
   /*
   * Plugin Name: Seriously Simple Podcasting
   * Version: 1.9.6
   * Plugin URI: https://wordpress.org/plugins/seriously-simple-podcasting/
   * Description: Podcasting the way it's meant to be.
   * Author: Hugh Lashbrooke
   * Author URI: http://www.hughlashbrooke.com/
   * Requires at least: 4.0
   * Tested up to: 4.2
   *
   * Text Domain: seriously-simple-podcasting
   * Domain Path: /lang/
   */
   

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8. PHP
   call_user_func()
   WordPress
   do_action()
   apply_filters()
   Events
   

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9. do_action( ‘hook’ );
   add_action( ‘hook’, ‘my_function’ );
   Events: Hooks
   

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10. add_action( ‘init’, ‘init_function’ );
    function init_function() {
    ...
    }
    Events: Hooks
    

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11. add_action( ‘hook’, ‘my_function’, 10 );
    Lower number == higher priority
    Events: Priorities
    

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12. add_action( ‘hook’, ‘my_function’, 10, 2 );
    function my_function ( $foo, $bar ) {
    ...
    }
    Events: Parameters
    

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13. apply_filters( ‘filter’, $foo );
    add_filter( ‘filter’, ‘my_function’ );
    Filters must always return a value
    Events: Filters
    

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14. add_filter( ‘body_class’, ‘my_function’ );
    function my_function( $classes ) {
    $classes[] = ‘my-class’;
    return $classes;
    }
    Events: Filters
    

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15. remove_action( ‘hook’, ‘function’ );
    remove_filter( ‘filter’, ‘function’ );
    Priorities must match original hook/filter
    Removing Hooks & Filters
    

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16. /*
    * Plugin Name: Google Redirect
    * Version: 1.0
    */
    add_action( ‘init’, ‘google_redirect’ );
    function google_redirect () {
    if( isset( $_GET[‘google_redirect’] ) ) {
    wp_redirect( ‘http://www.google.com’, 302 );
    exit;
    }
    }
    ?>
    Bringing it Together
    

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17. Plugin Developer Info: wordpress.org/plugins/about/
    Coding Standards: codex.wordpress.org/WordPress_Coding_Standards
    Action Reference: codex.wordpress.org/Plugin_API/Action_Reference
    Plugin Template: github.com/hlashbrooke/WordPress-Plugin-Template
    Helpful Links
    

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18. wpcapetown.co.za
    woothemes.com
    hughlashbrooke.com
    @hlashbrooke
    

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