Single_template for a custom post type created from a plugin is returning an empty page

Question

I'm trying to create a single template for the custom post type posts called 'press release' from a plugin.

This is the code I added to my plugin:

function single_press_release_template($single_template) {
     global $post;
     $plugin_path = plugin_dir_path( __FILE__ );
     if ($post->post_type == 'press_release') {
        if(file_exists($plugin_path . 'views/single-press_release.php')) {
            $single_template = $plugin_path . 'views/single-press_release.php';
            echo 'EXISTS! ' . $plugin_path . 'views/single-press_release.php';
        }
     }
     return $single_template;
}
add_filter( 'single_template', 'single_press_release_template');

The file single-press_release.php (located in the 'views' plugins directory) contains this code:

/**
 * Single Press Release
 *
 * @package WordPress
 */

<?php

echo 'Hello World';

?>

The result I get is a page without any main content (there is no 'hello world' text at all) but I can see the echo 'EXISTS! ' . $plugin_path . 'views/single-press_release.php':

What am I doing wrong?

Answer 1

So, the template file is there, but it doesn't get called, even though your function looks good (to me) as it does exactly what the codex says. The problem is therefore most probably caused by interference by your theme or another plugin that uses the same filter, overruling yours. You could solve that by giving your filter a higher priority:

add_filter ('single_template', 'single_press_release_template', 20 ,1);