Create new class object inside WordPress template

Question

I've a problem. My plan is it to create a new class object inside a WordPress template to pass a variable from the post object to it:

<?php
/**
 * Template Name: Ticket
 */

defined( 'ABSPATH' ) || exit;

new Test( $post->ID );

Inside my class I'm defining an action that adds a AJAX function inside the class:

class Test {
    public function __construct( $ticket_id ) {
        $this->ticket_id = $ticket_id;

        $this->register();
    }
    /**
     * Register all hooks
     */
    public function register(): void {
        add_action( 'wp_ajax_test', array( $this, 'test' ) );
    }
    public function test(): void {
        error_log($this->ticket_id);
    }
}

The problem is that the AJAX function is not reachable. Maybe it's added too late? Because when I create a new class object directly in my functions.php file, it's working. In this case I don't know how to get my post id inside my class.

Thanks for helping me out!

Answer 1

First things first:

With separation of concern in mind, you should not use your template to register anything. Your template should be as stupid as possible, as it is only there to render/display things.

Still, you have to call the register function:

$testClass = new Test( $post->ID );
$testClass->register();

WordPress has a live cycle. I'm not sure if you are able to add a new action there.