mikeschinkel/gist:503778

## gistfile1.php
<?php
/*
 * Example code showing how to hook WordPress to add fields to the taxonomny term edit screen.
 *
 * This example is meant to show how, not to be a drop in example.
 *
 * This example was written in response to this question:
 *
 *    http://lists.automattic.com/pipermail/wp-hackers/2010-August/033671.html
 *
 * By:
 *
 *    Mike Schinkel (http://mikeschinkel.com/custom-wordpress-plugins/)
 *
 * NOTE:
 *
 *    This could easily become a plugin if it were fleshed out.
 *    A class with static methods was used to minimize the variables & functions added to the global namespace.
 *    wp_options was uses with one option be tax/term instead of via a serialize array because it aids in retrival
 *    if there get to be a large number of tax/terms types. A taxonomy/term meta would be the prefered but WordPress
 *    does not have one.
 *
 * This example is licensed GPLv2.
 *
 */

// These are helper functions you can use elsewhere to access this info
function get_taxonomy_term_type($taxonomy,$term_id) {
	return get_option("_term_type_{$taxonomy}_{$term->term_id}");
}
function update_taxonomy_term_type($taxonomy,$term_id,$value) {
	update_option("_term_type_{$taxonomy}_{$term_id}",$value);
}

//This initializes the class.
TaxonomyTermTypes::on_load();

//This should be called in your own code. This example uses two taxonomies: 'region' & 'opportunity'
TaxonomyTermTypes::register_taxonomy(array('region','opportunity'));

class TaxonomyTermTypes {
	//This initializes the hooks to allow saving of the
	static function on_load() {
		add_action('created_term',array(__CLASS__,'term_type_update'),10,3);
		add_action('edit_term',array(__CLASS__,'term_type_update'),10,3);
	}
	//This initializes the hooks to allow adding the dropdown to the form fields
	static function register_taxonomy($taxonomy) {
		if (!is_array($taxonomy))
			$taxonomy = array($taxonomy);
		foreach($taxonomy as $tax_name) {
			add_action("{$tax_name}_add_form_fields",array(__CLASS__,"add_form_fields"));
			add_action("{$tax_name}_edit_form_fields",array(__CLASS__,"edit_form_fields"),10,2);
		}
	}
	// This displays the selections. Edit it to retrieve
	static function add_form_fields($taxonomy) {
		echo "Type " . self::get_select_html('text');
	}
	// This displays the selections. Edit it to retrieve your own terms however you retrieve them.
	static function get_select_html($selected) {
		$selected_attr = array('text'=>'','user'=>'','date'=>'','etc'=>'');
		$selected_attr[$selected] = ' selected="selected"';
		$html =<<<HTML
<select id="tag-type" name="tag-type">
	<option value="text"{$selected_attr['text']}>Text</option>
	<option value="user"{$selected_attr['user']}>User</option>
	<option value="date"{$selected_attr['date']}>Date</option>
	<option value="etc" {$selected_attr['etc']}>Etc.</option>
</select>
HTML;
		return $html;
	}
		// This a table row with the drop down for an edit screen
		static function edit_form_fields($term, $taxonomy) {
		$selected = get_option("_term_type_{$taxonomy}_{$term->term_id}");
		$select = self::get_select_html($selected);
		$html =<<<HTML
<tr class="form-field form-required">
	<th scope="row" valign="top"><label for="tag-type">Type</label></th>
	<td>$select</td>
</tr>
HTML;
		echo $html;
	}
	// These hooks are called after adding and editing to save $_POST['tag-term']
	static function term_type_update($term_id, $tt_id, $taxonomy) {
		if (isset($_POST['tag-type'])) {
			update_taxonomy_term_type($taxonomy,$term_id,$_POST['tag-type']);
		}
	}
}
	<?php
	/*
	* Example code showing how to hook WordPress to add fields to the taxonomny term edit screen.
	*
	* This example is meant to show how, not to be a drop in example.
	*
	* This example was written in response to this question:
	*
	* http://lists.automattic.com/pipermail/wp-hackers/2010-August/033671.html
	*
	* By:
	*
	* Mike Schinkel (http://mikeschinkel.com/custom-wordpress-plugins/)
	*
	* NOTE:
	*
	* This could easily become a plugin if it were fleshed out.
	* A class with static methods was used to minimize the variables & functions added to the global namespace.
	* wp_options was uses with one option be tax/term instead of via a serialize array because it aids in retrival
	* if there get to be a large number of tax/terms types. A taxonomy/term meta would be the prefered but WordPress
	* does not have one.
	*
	* This example is licensed GPLv2.
	*
	*/

	// These are helper functions you can use elsewhere to access this info
	function get_taxonomy_term_type($taxonomy,$term_id) {
	return get_option("_term_type_{$taxonomy}_{$term->term_id}");
	}
	function update_taxonomy_term_type($taxonomy,$term_id,$value) {
	update_option("_term_type_{$taxonomy}_{$term_id}",$value);
	}

	//This initializes the class.
	TaxonomyTermTypes::on_load();

	//This should be called in your own code. This example uses two taxonomies: 'region' & 'opportunity'
	TaxonomyTermTypes::register_taxonomy(array('region','opportunity'));

	class TaxonomyTermTypes {
	//This initializes the hooks to allow saving of the
	static function on_load() {
	add_action('created_term',array(__CLASS__,'term_type_update'),10,3);
	add_action('edit_term',array(__CLASS__,'term_type_update'),10,3);
	}
	//This initializes the hooks to allow adding the dropdown to the form fields
	static function register_taxonomy($taxonomy) {
	if (!is_array($taxonomy))
	$taxonomy = array($taxonomy);
	foreach($taxonomy as $tax_name) {
	add_action("{$tax_name}_add_form_fields",array(__CLASS__,"add_form_fields"));
	add_action("{$tax_name}_edit_form_fields",array(__CLASS__,"edit_form_fields"),10,2);
	}
	}
	// This displays the selections. Edit it to retrieve
	static function add_form_fields($taxonomy) {
	echo "Type " . self::get_select_html('text');
	}
	// This displays the selections. Edit it to retrieve your own terms however you retrieve them.
	static function get_select_html($selected) {
	$selected_attr = array('text'=>'','user'=>'','date'=>'','etc'=>'');
	$selected_attr[$selected] = ' selected="selected"';
	$html =<<<HTML
	<select id="tag-type" name="tag-type">
	<option value="text"{$selected_attr['text']}>Text</option>
	<option value="user"{$selected_attr['user']}>User</option>
	<option value="date"{$selected_attr['date']}>Date</option>
	<option value="etc" {$selected_attr['etc']}>Etc.</option>
	</select>
	HTML;
	return $html;
	}
	// This a table row with the drop down for an edit screen
	static function edit_form_fields($term, $taxonomy) {
	$selected = get_option("_term_type_{$taxonomy}_{$term->term_id}");
	$select = self::get_select_html($selected);
	$html =<<<HTML
	<tr class="form-field form-required">
	<th scope="row" valign="top"><label for="tag-type">Type</label></th>
	<td>$select</td>
	</tr>
	HTML;
	echo $html;
	}
	// These hooks are called after adding and editing to save $_POST['tag-term']
	static function term_type_update($term_id, $tt_id, $taxonomy) {
	if (isset($_POST['tag-type'])) {
	update_taxonomy_term_type($taxonomy,$term_id,$_POST['tag-type']);
	}
	}
	}