Moreover $kids <> "" should be replaced by !empty($kids) and I'm not sure that wordpress_mu_primary_blog_id has any meaning now that WP 3.0 has merged WP and WPMU...

Last, calling bb_list_pages() with no args, makes if ($depth == 0) true, resulting in an empty string returned. It would be good to use the same template of wp_list_pages(), which lists all pages if no param is passed to it (see docs). By the way, this could be the reason why you get nothing displayed when calling the function.

<?php echo bb_list_pages();?>

or modify the last few lines of the function from:

// Return the string to the caller
return $output;

to:

// Return the string to the caller
echo $output;
return;

then you can call the function similar to wp_list_pages()

<?php bb_list_pages();?>

This is how I understand the code:

function pages_table() {
global $bb; //calls global variable

// Compute the name of the table we need to query
$table = $bb->wp_table_prefix; //this calls the wp prefix from the wordpress integration settings, ex: wp_
if ($bb->wordpress_mu_primary_blog_id != "") //checks for a WPMU id in the WP integration settings
$table .= $bb->wordpress_mu_primary_blog_id."_"; //appends the id, ex: wp_1
$table .= "posts"; //appends "posts", ex: wp_posts or wp_1posts
return $table;
}

To answer your questions the code works no matter which type of WP flavor you are using

THANK U for sparing some time and help with me!

If you're using less than 1.0, you can create a plugin from that code. Just add a plugin header to the top of all that, like this:

<?php
/*
Plugin Name: WordPress pages for bbPress
*/
?>

And put it into file called something like wordpress-pages.php and drop that into folder called my-plugins at the same level as bb-plugins. If the folder is not there, you can create it. After it's in the folder, log into the admin, you should see it there, then activate it. And report back how it worked for you.

Thanks

Please note that this code does not attempt to reproduce all of the functionality of the WordPress wp_list_pages() function. Rather, it just tries to create the HTML needed for the drop down menu code that came with my WordPress theme to work. If you need anything more than that, feel free to modify this or strike out on your own.

Overview
Before the code, just a quick overview of how it works.

The function bb_list_pages() is a recursive function that returns a string containing the HTML for all of the pages that descend from a particular ancestor. The process is started by calling it with a parent ID of 0. The way the wp_posts table in WP is designed, this returns the highest level.

The function calls a helper function called get_pages() to retrieve the list of child pages from the database. It then loops through all of the pages returned by get_pages() & constructs the list item & anchor tags. It then calls itself to build the HTML for any descendants of the current page.

Here's the code:

<?php
	/**
	 * This file contains useful functions that can be called in any of the template's files.
	 *
	 * Version 1.0
	 * Date: 23-July-2009
	 * Author:  Tony Vitabile
	 */

	function curPageURL() {
		$pageURL = 'http';
		if ($_SERVER["HTTPS"] == "on") {$pageURL .= "s";}
		$pageURL .= "://".$_SERVER["SERVER_NAME"];
		if ($_SERVER["SERVER_PORT"] != "80") {
			$pageURL .= ":".$_SERVER["SERVER_PORT"];
		}
		$pageURL .= $_SERVER["REQUEST_URI"];

		return $pageURL;
	}

	/**
	 * Compute the name of the WordPress pages table & return it
	 */
	function pages_table() {
		global $bb;

		// Compute the name of the table we need to query
		$table = $bb->wp_table_prefix;
		if ($bb->wordpress_mu_primary_blog_id != "")
			$table .= $bb->wordpress_mu_primary_blog_id."_";
		$table .= "posts";
		return $table;
	}

	/**
	 * Retrieve a list of pages from the WordPress posts table whose parent has the ID
	 * passed to this function.
	 *
	 * @param int $parent ID of the page that is the parent of the ones we're searching for
	 * @return array List of pages matching defaults or $args
	 */
	function get_pages($parent = 0) {
		global $bbdb;

		// Compute the name of the table we need to query
		$table = pages_table();

		// Build our query string
		$parent = (int) $parent;
		$query = "SELECT * FROM {$table} WHERE post_type = 'page' AND post_status = 'publish' AND post_parent = {$parent} ORDER BY menu_order";

		// Get an array of rows back from the database
		$pages = $bbdb->get_results($query);

		// Return whatever we got back to the caller
		return $pages;
	}

	/**
	 * Simple function to recursively scan the WordPress posts table looking for pages.
	 * It builds a string consisting of <ul><li></li>...</ul> items.
	 *
	 * @param int $parent ID of the parent page.  0 = no parent
	 * @param int $depth  How far down in the heirarchy to go
	 * @param string $thisPage The name of the page that is currently being displayed
	 * @returns string A <ul><li></li>...</ul> list of page navigation information
	 */

	function bb_list_pages($parent = 0, $depth=0, $parent_uri='', $indent='    ') {
		// Initialize the output of the function
		$output = "";

		// Is the depth = 0?
		if ($depth == 0) {
			// It is.  Return the empty string now
			return $output;
		}

		// Get the child rows of $parent
		$pages = get_pages($parent);

		// Did we get any pages back?
		if ( empty($pages) ) {
			// No, we didn't.  Return the empty string now
			return $output;
		}

		// Yes, we got pages back.  Loop through all of the pages in our results
		foreach ( $pages as $page ) {
			// Compute this page's URI
			$page_uri = $parent_uri;
			if (substr($page_uri, -1) != '/')
				$page_uri .= "/";
			$page_uri .= $page->post_name . "/";

			// Build the <li> tag
			$output .= "{$indent}<li class=\"page_item page-item-{$page->ID}";
			if ($page_uri == curPageURL() ) {
				$output .= " current_page_item";
			}
			$output .= "\">";

			// Now build the rest of this item's information
			$output .= "<a href=\"{$page_uri}\">".$page->post_title."</a>\n";

			if ($page->ID > 0) {
				// Get this page's children recursively
				$kids = bb_list_pages($page->ID, $depth -1, $page_uri, '', $thisPage, $indent . "  ");

				// Does this page have any children?
				if ($kids <> "") {
					// It does.  Add the information for the kids surrounded by <ul></ul> tages
					$output .= "{$indent}<ul>\n" . $kids . "{$indent}</ul>\n";
				}
			}

			// Output the closing </li>
			$output .= "</li>";
		}

		// Return the string to the caller
		return $output;
	}

?>

Tony