4 - Developers: How to create a DraggableViews handler
Last modified: October 15, 2009 - 22:30
This page will describe the DraggableViews Taxonomy handler that comes with the DraggableViews module. This page doesn't assume that the user knows how to build drupal modules.
First create a new folder for the new module:
yourdrupalsite/sites/all/modules/your-module-name
(The taxonomy handler is located in sites/all/modules/draggableviews/modules/draggableviews_taxonomy)
The files we need:
- your-module-name.info
- your-module-name.module
- draggableviews_handler_your-module-name.inc
The content of your-module-name.info
; $Id: your-module-name.info,v 1.1 2009/08/19 14:17:58 YOUR_NAME Exp $
name = DraggableViews your-module-name handler
description = Provides Taxonomy support for both order fields and parent fields.
dependencies[] = draggableviews
dependencies[] = your-module-name
package = Views
core = 6.xThe content of your-module-name.module
<?php
// $Id: your-module-name.module,v 1.1 2009/08/19 14:17:58 YOUR_NAME Exp $
/**
* @file
* DraggableViews your-module-name module provides taxonomy support for both order fields and parent fields.
*/
/**
* Display help and module information
* @param path which path of the site we're displaying help
* @param arg array that holds the current path as would be returned from arg() function
* @return help text for the path
*/
function draggableviews_your-module-name_help($path, $arg) {
$output = '';
switch ($path) {
case "admin/help#draggableviews_your-module-name":
$output = '<p>'. t("Taxonomy support for both order fields and parent fields.") .'</p>';
$output .= '<p>'. t("Hint: Use Views relations to turn the Taxonomy: Term ID field into a parent field.") .'</p>';
break;
}
return $output;
}
/**
* Implementing hook_draggableviews_handlers
*/
function draggableviews_your-module-name_draggableviews_handlers() {
return array(
'your-module-name' => array(
'file' => 'draggableviews_handler_your-module-name.inc',
'title' => t('Taxonomy 2'),
'description' => 'Taxonomy handler.',
'handler' => 'draggableviews_handler_your-module-name',
),
);
}
?>The
hook_draggableviews_handlers tells DraggableViews that this handler is available and where to find it. The file attribute can be omitted, it will default to "handler.inc" ("draggableviews_handler_your-module-name.inc"). The handler can be omitted to, it will default too "draggableviews_handler_your-module-name". The title is for the UI. The description will not be shown anywhere (..not yet).You should omit the trailing ?> tag in this file.
The content of draggableviews_handler_your-module-name.inc
<?php
// $Id: draggableviews_handler_your-module-name.inc,v 1.1.2.1 2009/08/19 14:17:58 YOUR_NAME Exp $
/**
* @file
* The taxonomy handler.
*/
/*
* Taxonomy handler.
*/
class draggableviews_handler_your-module-name extends draggableviews_handler {
function init($field_name, &$view) {
parent::init($field_name, $view);
}
function save($tid, $value) {
switch ($this->type) {
case 'order':
db_query("UPDATE {term_data} SET weight=%d WHERE tid=%d", $value, $tid);
break;
case 'hierarchy':
db_query("UPDATE {term_hierarchy} SET parent=%d WHERE tid=%d", $value, $tid);
break;
}
}
function get_form_element($value, $attributes = array()) {
if (!isset($attributes['class'])) $attributes['class'] = $field['field_name'];
switch ($this->type) {
default:
$options = array();
for ($i = $this->range_start; $i <= $this->range_end; $i++) $options[$i] = $i;
return array(
'#type' => 'select',
'#name' => $attributes['field_name'],
'#value' => $value,
'#options' => $options,
'#attributes' => array('class' => $attributes['class']),
);
break;
case 'hierarchy':
return array(
'#type' => 'hidden',
'#name' => $attributes['field_name'],
'#value' => $value,
'#attributes' => array('class' => $attributes['class']),
);
}
}
}
?>The
$field_name and $view variables that will be passed to function init() contain all the information we might possibly need. Actually we would need two handlers: One for the order field and one for the parent field. This handler uses a switch where we distinguish between these two handlers.In
function get_form_element() you can return any custom input field as long as its containing value can be read from the tabledrag.js.
The method save($tid, $value) must be implemented.
All the three methods init() and get_form_element() can optionally be implemented. If you don't implement them the default implementation of the parent class will be used.
You should omit the trailing ?> tag in this file.