<?php 
add_action( 'add_meta_boxes', 'add_product_box' );
function add_product_box(){
    add_meta_box( 'product_sticky', '文章置顶', 'product_sticky', 'product_type', 'side', 'high' );
}
function product_sticky (){
?>
<ul>
    <li style="margin-top:6px;">
        <input id="super-sticky" name="sticky" type="checkbox" value="sticky" <?php checked( is_sticky() ); ?>/> <label for="super-sticky" class="selectit" style="vertical-align: top">推荐阅读</label>
    </li>    
</ul>
<?php } ?>

<?php 
	$sticky = get_option('sticky_posts');			
	query_posts( array('showposts'=>'10', 'post__in' => $sticky, 'ignore_sticky_posts' => 1,'post_status' => 'publish','post_type' => 'product_type' ) );
	if (have_posts()) :
		while (have_posts()) : the_post();
?>
<li><a href="<?php the_permalink(); ?>" title="<?php the_title(); ?>"><?php the_title(); ?></a></li>
<?php 
		endwhile;
	endif; 
	wp_reset_query();
?>