These are the slides for my talk at WordCamp in Ottawa 2014 http://2014.ottawa.wordcamp.org/

1. Extending Gravity
Forms
A CODE DEEP DIVE

2. Paul Bearne @pbearne
Sr. Web Developer @ metronews.ca
Plugin author of Author Avatars List ( http://wordpress.org/plugins/author-avatars/ )
WP Site Verification tool ( http://wordpress.org/plugins/wp-site-verification-tool/ )

3. Agenda
Gravity forms demo
Options overload demo
Options overload code
Metro AR demo
AR from code
Class overload demo
Class overload code

4. DEMO
GRAVITY FORMS

5. add_filter( 'gform_pre_render', array( $this, ‘overload_gform_select_with_basecamp_user_list’), 10 );
public function overload_gform_select_with_basecamp_user_list( $form ){
$new_user_choices = null;
// check we have a basecamp class
$this->create_basecamp();
// lets get all basecamp users for this project
$message = $this->basecamp->getPeople(); // whole account
if( null == $message ){
return $form;
}
// loop basecamp users
foreach( $message as $basecamp_user ){
$isSelected = ($this->current_user->user_email == $basecamp_user->email_address)?true:false;
$new_user_choices[] = array(
"text"=>esc_html( $basecamp_user->name ),
"value"=>absint( $basecamp_user->id ),
"isSelected"=>( bool )$isSelected,
"price"=>""
);
}
// loop all field and look for users
foreach( $form['fields'] as &$field ){
if( in_array( $field['inputName'], $this->basecamp_user_fields ) ){
$field['choices'] = $new_user_choices;
}
}
return $form;
}

6. add_filter( 'gform_pre_render', 'overload_gform_select_with_user_list', 10 );
function overload_gform_select_with_user_list( $form ){
$new_user_choices = null;
// create an array of new option values
$new_user_choices[] = array( 'text‘=>'admin', 'value'=>1, 'isSelected'=>false, 'price'=>'' );
$new_user_choices[] = array( 'text'=>'Paul Bearne', 'value'=>2, 'isSelected'=>true, 'price'=>'' );
$new_user_choices[] = array( 'text'=>'Username', 'value'=>3, 'isSelected'=>false, 'price'=>'' );
// loop all fields and look for Parameter Name
foreach( $form['fields'] as &$field ){
if( in_array( $field['inputName'], 'Parameter_Name') ){
$field['choices'] = $new_user_choices;
}
}
return $form;
}

7. DEMO
METRO AR FORM

8. <?php
require_once 'external-web-services/PostNewTarget.php';
class mec_send_to_external_api
{
private $form_id;// id of the gravity form being used
function __construct()
{
// store the form id in options
$options = get_option('basecamp_form_options');
$this->form_id = ( isset( $options['ar'] ) )?$options['ar']:1;
add_action('gform_after_submission_'.$this->form_id, array( $this, mec_send_to_external_api'
), 10, 2 );
);
}
public function mec_send_to_external_api( $entry, $form ){
// map the gravity form fields to nice names
$target_name = $entry[8];
$target_short_title = $entry[14];
$target_french_short_title = $entry[15];
$target_long_title = $entry[16];
$target_french_long_title = $entry[17];
$target_image_url = $entry[2];
$target_opacity = ( float )$entry[9];
$target_overlay_type = $entry[10];
$overlay_web_url = $entry[1];
$overlay_web_internal_links = explode( ',', '' );
$overlay_web_external_links = explode( ',', '' );
$overlay_web_interactive = true;
$overlay_video_url = ( 0 < strlen( $entry[12] ) )?$entry[12]:$entry[3];
$overlay_image_url = $entry[7];
$overlay_gallery = json_decode( $entry[5] );
$overlay_gallery_caption = '';
$overlay_opacity = ( float )$entry[11];
// which overtype are we loading
switch ( $target_overlay_type ) {
case 'gallery':
$src_urls = null;
if( empty( $overlay_gallery ) ){
wp_die( "No Images in upload for gallery", 'Upload failed' );
}
$overlay_gallery = array_reverse($overlay_gallery,true);
foreach ($overlay_gallery as $key => $image_url) {
$images = null;
$resizes = make_image_resizes( parse_url( $image_url, PHP_URL_PATH ) );
$folder_URL = implode( '/',( explode( '/', $image_url, -1 ) ) );
if(false == $resizes){
wp_die( "image resize failed", 'Upload failed' );
}
foreach ($resizes as $row) {
$images[ $row['width'] ] = $folder_URL.'/'.$row['file'] ;
}
$images["src"] = $image_url ;
$images["caption"] = $overlay_gallery_caption ;
$src_urls[] = $images;
}
$type = array("images" => $src_urls );
break;
case 'video':
$type["src"] = $overlay_video_url ;
break;

9. case 'image':
$resizes = make_image_resizes( parse_url( $overlay_image_url, PHP_URL_PATH ) );
$folder_URL = implode( '/',( explode( '/', $overlay_image_url, -1 ) ) );
foreach ($resizes as $row) {
$type[ $row['width'] ] = $folder_URL.$row['file'] ;
}
$type["src"] = $overlay_image_url ;
break;
case 'web':
$type["src"] = $overlay_web_url ;
$type["force_internal"] = $overlay_web_internal_links;
$type["force_external"] = $overlay_web_external_links;
$type["interactive_while_tracking"] = $overlay_web_interactive;
break;
default:
$type = array(); // just in case
break;
}
$metadata = array( $target_overlay_type => $type );
$metadata['tracking_opacity'] = $target_opacity;
$metadata['centered_opacity'] = $overlay_opacity;
$metadata['title'] = $target_short_title;
$metadata['title_fr'] = $target_french_short_title;
$metadata['title_long'] = $target_long_title;
$metadata['title_long_fr'] = $target_french_long_title;
$response_text = "";
$date = new DateTime( "now", new DateTimeZone( "GMT" ) );
$external = new PostNewTarget();
$external->targetName = $target_name.$date->format( " Y-m-d-H:i:s" );
$external->imageLocation = $target_image_url;
$external->application_metadata = json_encode( $metadata );
$response = $external->push();
$response_text = $response->getBody();
}
}
$mec_send_to_external_api = new mec_send_to_external_api();

10. <?php
// note the 2 at the end it tell the add action to pass 2 values to the function
add_action('gform_after_submission_1', 'send_to_external_api', 10, 2 );
}
function send_to_external_api( $entry, $form ){
// 2 option radio button note the 18.1
$do_publish = ( isset( $entry['18.1'] ) && true == $entry['18.1'] )? false : true;
// esc text
$metadata['target_name'] = esc_html( $entry[8] );
// alsway cast numbers
$metadata['overlay_opacity'] = ( float )$entry[11];
// how to test for a value and switch
$metadata['video_url'] = ( 0 < strlen( $entry[12] ) )?$entry[12]:$entry[3];
// URL end up commara seperated
$metadata['_web_links'] = explode( ',', '' );
//file upload is a json srting so needs to decoding
$metadata['gallery'] = json_decode( $entry[5] );
// if you need to switch on a value been there just look for it in array
// works for selects / radio button and check boxs as you set the return values
$metadata['value_set'] = ( in_array( 'look_for_me', $entry, true ) )?true:false;
// encode value so we can send them
$args['body'] = json_encode( $metadata );
$url = 'http://somerandomserver.com/api';
//http://codex.wordpress.org/HTTP_API
//http://codex.wordpress.org/Function_Reference/wp_remote_post
wp_remote_post( $url, $args );
}

11. <?php
// 175 id of form
// 1 the id of form element
// send 4 values to function
add_filter("gform_field_validation_175_1", "custom_validation", 10, 4);
function custom_validation($result, $value, $form, $field){
// check have been passed is_valid as an array object
// perform a test
if(array_key_exists( "is_valid", $result ) && intval($value) > 10){
// make it invalid
$result["is_valid"] = false;
// and nice message
$result["message"] = "Please enter a value less than 10";
}
// return the update array
return $result;
}

12. https://github.com/rocketgenius/simpleaddon/blob/master/simpleaddon.php
https://github.com/rocketgenius/simpleaddon
<?php
/*
Plugin Name: Gravity Forms Simple Add-On
Plugin URI: http://www.gravityforms.com
Description: A simple add-on to demonstrate the use of the Add-On Framework
Version: 1.1
Author: Rocketgenius
Author URI: http://www.rocketgenius.com
------------------------------------------------------------------------
Copyright 2012-2013 Rocketgenius Inc.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/

13. if (class_exists("GFForms")) {
GFForms::include_addon_framework();
class GFSimpleAddOn extends GFAddOn {
protected $_version = "1.1";
protected $_min_gravityforms_version = "1.7.9999";
protected $_slug = "simpleaddon";
protected $_path = "asimpleaddon/asimpleaddon.php";
protected $_full_path = __FILE__;
protected $_title = "Gravity Forms Simple Add-On";
protected $_short_title = "Simple Add-On";
public function init(){
parent::init();
add_filter("gform_submit_button", array($this, "form_submit_button"), 10, 2);
}
// Add the text in the plugin settings to the bottom of the form if enabled for this form
function form_submit_button($button, $form){
$settings = $this->get_form_settings($form);
if(isset($settings["enabled"]) && true == $settings["enabled"]){
$text = $this->get_plugin_setting("mytextbox");
$button = "<div>{$text}</div>" . $button;
}
return $button;
}

14. public function plugin_page() {
?>
This page appears in the Forms menu
<?php
}
public function form_settings_fields($form) {
return array(
array(
"title" => "Simple Form Settings",
"fields" => array(
array(
"label" => "My checkbox",
"type" => "checkbox",
"name" => "enabled",
"tooltip" => "This is the tooltip",
"choices" => array(
array(
"label" => "Enabled",
"name" => "enabled"
)
)
),……….

15. public function settings_my_custom_field_type(){
?>
<div>
My custom field contains a few settings:
</div>
<?php
$this->settings_text(
array(
"label" => "A textbox sub-field",
"name" => "subtext",
"default_value" => "change me"
)
);
$this->settings_checkbox(
array(
"label" => "A checkbox sub-field",
"choices" => array(
array(
"label" => "Activate",
"name" => "subcheck",
"default_value" => true
)
)
)
);
}

16. public function plugin_settings_fields() {
return array(
array(
"title" => "Simple Add-On Settings",
"fields" => array(
array(
"name" => "mytextbox",
"tooltip" => "This is the tooltip",
"label" => "This is the label",
"type" => "text",
"class" => "small"
)
)
)
);
}

17. public function scripts() {
$scripts = array(
array("handle" => "my_script_js",
"src" => $this->get_base_url() . "/js/my_script.js",
"version" => $this->_version,
"deps" => array("jquery"),
"strings" => array(
'first' => __("First Choice", "simpleaddon"),
'second' => __("Second Choice", "simpleaddon"),
'third' => __("Third Choice", "simpleaddon")
),
"enqueue" => array(
array(
"admin_page" => array("form_settings"),
"tab" => "simpleaddon"
)
)
),
);
return array_merge(parent::scripts(), $scripts);
}

18. public function styles() {
$styles = array(
array("handle" => "my_styles_css",
"src" => $this->get_base_url() . "/css/my_styles.css",
"version" => $this->_version,
"enqueue" => array(
array("field_types" => array("poll"))
)
)
);
return array_merge(parent::styles(), $styles);
}
}
new GFSimpleAddOn();
}

19. Questions?

20. The Add-On frameworkis gearedtowards developersbuildingGravity Forms Add-Ons.It has a setof classesthatcan be extended and makethe taskof creatingan Add-On muchsimplerthan before.
The followingdocumentationpage shouldgive you a good overviewand it also linksto a coupleof sampleAdd-Onsthatyou can download from Git Hub to see thingsin action.
http://www.gravityhelp.com/documentation/page/Add-On_Framework
The WebAPI allows remoteprogramaticaccessto Gravity Form.It can be usedfor example,to implementa mobileapp,or anytimeyou needto performoperationson yourGravity Forms sitefrom a remotesite.
The followingdocumentationpage shouldgive you a good overview:
http://www.gravityhelp.com/documentation/page/Web_API
gform_pre_render–
http://www.gravityhelp.com/documentation/page/Gform_pre_render
gform_field_validation- Allows customvalidationto be doneon a specificfield.
http://www.gravityhelp.com/documentation/page/Gform_field_validation
gform_after_submission- Allows tasksto be performedaftera successfulsubmission.
http://www.gravityhelp.com/documentation/page/Gform_after_submission

21. Slides@ http://www.slideshare.net/pbearne
Email: pbearne@gmail.com