How to sort list of custom posts to get view like a tree of posts under categories and their children's categories?

Question

I'm new here and my english isn't perfect so I'm sorry for this :) I'm here because I'm workin on site with post list sorted by category and I have problem with sort out my posts in categories and children categories under them. Now everything is messed up. I would like to sort my custom posts like that:

CATEGORY 1

• CHILD CATEGORY 1

  • Post
  • Post
  • Post

• CHILD CATEGORY2

  • Post
  • Post
  • Post

CATEGORY 2

• CHILD CATEGORY3
  • Post
  • Post
  • Post

CATEGORY 3

• Post

• Post

• CHILD CATEGORY4

  • Post
  • Post
  • Post

Is it possible with this code:

<?php
$querystr = "SELECT terms.* FROM $wpdb->term_taxonomy tax LEFT JOIN $wpdb->terms terms ON       tax.term_id = terms.term_id WHERE tax.taxonomy = 'MY_CUSTOM_TAXONOMY'";

$categories = $wpdb->get_results($querystr, OBJECT);

foreach( $categories as $category ): 
echo '<div class="category-header"><h3>'.$category->name.'</h3>';  
echo '<p class="category-description">'.strip_tags(term_description($category->term_id,'MY_CUSTOM_TAXONOMY')).'</p></div>';  

$posts = get_posts( array( 'MY_CUSTOM_TAXONOMY' => $category->name, 'post_type' => 'MY_CUSTOM_POST' ) );  
foreach($posts as $post) :  
setup_postdata($post);  

 the_title();   

endforeach;

endforeach;
?>

I will be grateful for all help, thank You!!

Answer 1

I played a little and this is what I came up with, I tested and it works just like your given example:

<ul>
<?php

// get initial categories
$categories = get_categories();

foreach ( $categories as $category ) {

// we don't want child categories now, and since get_categories does not support 'depth' parameter, we use ->parent check
if ( $category->parent > 0 ) {
    continue;   
}

$i = 0;
echo '<li>' . $category->cat_name . '</li>';

$posts = get_posts(
    array(
        'category' => $category->term_id
    )
);

foreach ( $posts as $post ) {

    // let's make sure that the post is not also in any of child categories, if it is, skip it ( we don't want to display it twice )
    $child_categories = get_term_children( $category->term_id, 'category' );

    if ( $child_categories && in_category( $child_categories, $post->ID ) ) {
        continue;
    }

    echo 0 === $i ? '<ul>' : '';
    echo '<li>' . $post->post_title . '</li>';
    $i++;

}

// now, after we listed all the posts, we query for child categories
$categories2 = get_categories(
    array(
        'parent' => $category->term_id
    )
);

foreach ( $categories2 as $category ) {

    $j = 0;
    echo '<li>' . $category->cat_name . '</li>';
    $posts2 = get_posts(
        array(
            'category' => $category->term_id
        )
    );

    foreach ( $posts2 as $post ) {

        echo 0 === $j ? '<ul>' : '';
        echo '<li>' . $post->post_title . '</li>';
        $j++;
    }

    echo null === $posts2 ? '' : '</ul>';

}

echo null === $posts ? '' : '</ul>';

}

?>
</ul>

Answer 2

ok, this is my working solution:

<?php

$args=array(
'post_type'                => 'biblioteka',
'child_of'                 => 0,
'parent'                   => '',
'orderby'                  => 'name',
'order'                    => 'ASC',
'hide_empty'               => 1,
'hierarchical'             => 1,
'exclude'                  => '',
'include'                  => '',
'number'                   => '',
'taxonomy'                 => 'kategoria-pozycji',
'pad_counts'               => false
);

$categories=get_categories($args);

foreach ( $categories as $category ) {

if ( $category->parent > 0 ) {
continue;   
}

echo '<h1 style="font-weight:bold">' . $category->name . '</h1>';

$querystr = "SELECT $wpdb->posts.*
          FROM $wpdb->posts, $wpdb->term_relationships, $wpdb->terms
          WHERE term_id = (" . $category->cat_ID . ")
          AND term_taxonomy_id = (" . $category->term_taxonomy_id . ")
          AND ID = object_id
          AND post_type = 'biblioteka'
          AND post_status = 'publish'
          ORDER BY post_date DESC";
$posts = $wpdb->get_results($querystr, OBJECT);

echo '<ul>';
foreach ( $posts as $post ) {
    setup_postdata($post);  

        echo '<li>'; the_title();   echo '</li>';

        }
echo '</ul>';

$categories2 = get_terms('kategoria-pozycji',array('parent' => $category->term_id , 'hide_empty'=> '0' ));

foreach ( $categories2 as $category ) {

echo '<h2>' . $category->name . '</h2>';

$posts = get_posts( array( 'kategoria-pozycji' => $category->name, 'post_type' => 'biblioteka' ) );  

echo '<ul>';
foreach($posts as $post) { 
    setup_postdata($post);  

        echo '<li>'; the_title();   echo '</li>';

        }
echo '</ul>';

}
}

?>