drupal_set_message – AgileAdam.com

As you may know, drupal_set_message() is deprecated in Drupal 8.5.0.

Here’s a quick example of using dependency injection to use the new Messenger service:

mymodule.services.yml

services:
  mymodule.authentication:
    class: Drupal\mymodule\MymoduleAuthentication
    arguments: ['@messenger']

services:

mymodule.authentication:

class: Drupal\mymodule\MymoduleAuthentication

arguments: ['@messenger']

src/MymoduleAuthentication.php

<?php

namespace Drupal\mymodule;

use Drupal\Core\Messenger\MessengerInterface;

/**
 * Provides authentication functionality for my module.
 *
 * @package Drupal\mymodule
 */
class MymoduleAuthentication {

  /**
   * Include the messenger service.
   *
   * @var \Drupal\Core\Messenger\MessengerInterface
   */
  protected $messenger;

  /**
   * Constructor.
   */
  public function __construct(MessengerInterface $messenger) {
    $this->messenger = $messenger;
  }

  /**
   * Shows a "Hello, world" message.
   */
  private function showHelloWorldMessage() {
    $this->messenger->addMessage('Hello, world');
  }

}

<?php

namespace Drupal\mymodule;

use Drupal\Core\Messenger\MessengerInterface;

/**

* Provides authentication functionality for my module.

* @package Drupal\mymodule

class MymoduleAuthentication {

/**

* Include the messenger service.

* @var \Drupal\Core\Messenger\MessengerInterface

protected $messenger;

/**

* Constructor.

public function __construct(MessengerInterface $messenger) {

$this->messenger = $messenger;

}

/**

* Shows a "Hello, world" message.

private function showHelloWorldMessage() {

$this->messenger->addMessage('Hello, world');

}