How to show only the most recent post on my custom post type archive?

Question

I have registered a custom post type and inside my archive-myCPT.php I want to retrieve just the current published post.

Here is a relevant snippet from my archive-myCPT.php:

<?php 

    if( have_posts() ){
        $x = 1;
        while ( have_posts() ){
            the_post(); 
            if ( 0 === (int) $post->post_parent ) {
                get_template_part( 'inc/post-format/content-debate');
            }

I've tried adding this : query_posts('posts_per_page=1&order=DESC&orderby=date') before the if( have_posts() ){ but I'm getting the last post from the default blog posts not from my CPT and also it adds also a pagination.

How can I retrieve just the most recent published post inside my CPT without the pagination?

Answer 1

You could just alter the main query for your custom post type archive with pre_get_posts().

Code:

function wpse124228_alter_ppp_order_for_mycpt( $query ) {
    if ( ! $query->is_main_query() || is_admin() )
        return;
    if ( is_post_type_archive( 'mycpt' ) ) {
        //Only display 1 post on mycpt archive
        $query->set( 'posts_per_page', 1 );
        //Most recent/current
        $query->set( 'orderby', 'date' );
        $query->set( 'order', 'DESC' );
    }
}
add_action( 'pre_get_posts', 'wpse124228_alter_ppp_order_for_mycpt' );

This pretty much resembles this example from the codex page. BTW don't use query_posts(), if you have to do a second query go with WP_Query, but for an archive that shouldn't be necessary.

Additional Information:

• Template_Hierarchy: Custom_Post_Types_display
• Post_Types: Custom_Post_Types
• Custom Post Type Templates
• How to Create a Custom Post Types Archive Page in WordPress