custom_post_types.php

<?php 

// Simple WordPress custom post type example for WP3.0+
// More info at http://curtishenson.com/wordpress-custom-post-types-and-meta-boxes-example

//These two lines initiate everything
add_action( 'init', 'CHLinksInit' );
function CHLinksInit() { global $ch_links; $ch_links = new CHLinks(); }

class CHLinks {
	
	function CHLinks() {
		register_post_type( 'link',
			array(
				'label' => __( 'Link Post' ),
				'singular_label' => __( 'Link Post' ),
				'public' => true,
				'menu_position' => 5,
				'query_var' => true,
				'supports' => array('title', 'editor'),
				'rewrite' => array('slug'=>'link'),
				'taxonomies' => array('post_tag')
			)
		);
		
		add_action("admin_init", array(&$this, "admin_init"));
		add_action('save_post', array(&$this, 'save_post_data'));
		
		// Add custom post navigation columns
		add_filter("manage_edit-link_columns", array(&$this, "nav_columns"));
		add_action("manage_posts_custom_column", array(&$this, "custom_nav_columns"));
		
		// If you want to use a custom template name
		add_action("template_redirect", array(&$this, 'template_redirect'));	
	}
	
	function admin_init(){
		add_meta_box("link-url-meta", "Link URL", array(&$this, "link_url_meta_box"), "link", "normal", "high");
	}
	
	function link_url_meta_box() {
		global $post;
		$meta = get_post_meta($post->ID, 'ch_link_url', true);
		
		// Verify
		echo'<input type="hidden" name="ch_link_url_noncename" id="ch_link_url_noncename" value="'.wp_create_nonce( plugin_basename(__FILE__) ).'" />';
		
		// Fields for data entry
	  	echo '<label for="ch_link_url" style="margin-right: 10px;">Enter Link URL:</label>';
	  	echo '<input type="text" name="ch_link_url" value="'.$meta.'" size="50" />';
	}
	
	function save_post_data( $post_id ) {
		global $post;
		
		// Verify
		if ( !wp_verify_nonce( $_POST["ch_link_url_noncename"], plugin_basename(__FILE__) )) {
			return $post_id;
		}
		if ( 'page' == $_POST['post_type'] ) {
			if ( !current_user_can( 'edit_page', $post_id ))
				return $post_id;
		} else {
			if ( !current_user_can( 'edit_post', $post_id ))
				return $post_id;
		}
	
		$data = $_POST['ch_link_url'];
		
		// New, Update, and Delete
		if(get_post_meta($post_id, 'ch_link_url') == "") 
			add_post_meta($post_id, 'ch_link_url', $data, true);
		elseif($data != get_post_meta($post_id, 'ch_link_url', true))
			update_post_meta($post_id, 'ch_link_url', $data); 
		elseif($data == "")
			delete_post_meta($post_id, 'ch_link_url', get_post_meta($post_id, 'ch_link_url', true));
	}
	
	function nav_columns($columns) {
		$columns = array(
			"cb" => "<input type=\"checkbox\" />",
			"title" => "Link Title",
			"link_description" => "Description",
			"link_url" => "Link URL",
		);
		
		return $columns;
	}
	
	function custom_nav_columns($column) {
		global $post;
		switch ($column) {
  			case "link_description":
  				the_excerpt();
  				break;
  			case "link_url":
  				$meta = get_post_custom();
  				echo $meta["ch_link_url"][0];
  				break;
		}
	}
	
	// If you want to use a custom template name you can use template_redirect()
	// WP defaults to single-"custom-post-name".php
	function template_redirect() {
		global $wp;
		if ($wp->query_vars["post_type"] == "link") {
			include(TEMPLATEPATH . "/single-link.php");
			die();
		}
	}
}