How can I get only 1 message from each category in wordpress

Question

I have a category called news and many subcategories inside it. I want to do to get only 1 message (latest) from each of these subcategories (including category name, job title, attachment image). Are friends friends?

Answer 1

<?php

$news_cat_ID = get_cat_ID( 'News' ); 
$news_cats   = get_categories( "parent=$news_cat_ID" );
$news_query  = new WP_Query;

foreach ( $news_cats as $news_cat ) :
    $news_query->query( array(
        'cat'                 => $news_cat->term_id,
        'posts_per_page'      => 1,
        'no_found_rows'       => true,
        'ignore_sticky_posts' => true,
    ));

    ?>

    <h2><?php echo esc_html( $news_cat->name ) ?></h2>

    <?php while ( $news_query->have_posts() ) : $news_query->the_post() ?>

            <div class="post">
                <?php the_title() ?>
                <!-- do whatever you else you want that you can do in a normal loop -->
            </div>  

    <?php endwhile ?>

<?php endforeach ?>

Answer 2

After a few hours and thanks to our comrades around the world, I was able to change the main request, so we don’t even need to go through the templates and generate new requests and loops ...

// My function to modify the main query object
function grouped_by_taxonomy_main_query( $query ) {

    if ( $query->is_home() && $query->is_main_query() ) { // Run only on the homepage

        $post_ids = array();

        $terms = get_terms('formato');

        foreach ( $terms as $term ) {
            $post_ids = array_merge( $post_ids, get_posts( array( 
                'posts_per_page' => 4, // as you wish...
                'post_type' => 'video', // If needed... Default is posts
                'fields' => 'ids', // we only want the ids to use later in 'post__in'
                'tax_query' => array( array( 'taxonomy' => $term->taxonomy, 'field' => 'term_id', 'terms' => $term->term_id, )))) // getting posts in the current term
            );
        }

        $query->query_vars['post_type'] = 'video'; // Again, if needed... Default is posts
        $query->query_vars['posts_per_page'] = 16; // If needed...
        $query->query_vars['post__in'] = $post_ids; // Filtering with the post ids we've obtained above
        $query->query_vars['orderby'] = 'post__in'; // Here we keep the order we generated in the terms loop
        $query->query_vars['ignore_sticky_posts'] = 1; // If you dont want your sticky posts to change the order

    }
}

// Hook my above function to the pre_get_posts action
add_action( 'pre_get_posts', 'grouped_by_taxonomy_main_query' );