How to control display of page lists on sidebar that doesn't have childrens

Question

I am using the following code to list the child pages of current page on my sidebar. It is working very well.

$titlenamer = get_the_title($post->post_parent);
$output = wp_list_pages('echo=0&depth=1&title_li=<div id="list-title-head">'.$titlenamer.'</div>' );
if (is_page( )) {
  $page = $post->ID;
  if ($post->post_parent) {
    $page = $post->post_parent;
  }
  $children=wp_list_pages( 'echo=0&child_of=' . $page . '&title_li=' );
  if ($children) {
    $output = wp_list_pages ('echo=0&child_of=' . $page . '&title_li=<div id="list-title-head">'.$titlenamer.'</div>');
  }
}
echo $output;

But If a parent menu has no childs, this code will list all the parent pages on my sidebar. How can I control this?

If the parent menu doesn't have any childs, then I wants to display certains pages I define. If this is not possible, I don't want to display anything for page that doesn't have childs.

Answer 1

I would try replacing your $children definition, using get_page_children() or get_children():

<?php
global $post;
$children = get_children( array(
    'post_type'   => 'page',
    'post_parent' => $post->ID,
    'post_status' => 'publish'
) );
if ( $children ) {
    // Code to list child pages goes here
}
?>

Also, wp_list_pages() will always return a string (either populated or empty), so if you're going to test against it, use:

if ( '' != $children )

...instead of just:

if ( $children )

Because the latter will always return true, since the return is an (empty) string.