Issue #2987316 by Mile23: Always inject services in controllers and forms

Author: Mile23

ajax_example/src/Form/Wizard.php

@@ -6,6 +6,7 @@
 use Drupal\Core\Form\FormStateInterface;
 use Drupal\Core\Url;
 use Drupal\Core\Link;
+use Symfony\Component\DependencyInjection\ContainerInterface;
 
 /**
  * AJAX example wizard.
@@ -19,6 +20,18 @@ public function getFormId() {
     return 'ajax_example_wizard';
   }
 
+  /**
+   * {@inheritdoc}
+   */
+  public static function create(ContainerInterface $container) {
+    // Since FormBase uses service traits, we can inject these services without
+    // adding our own __construct() method.
+    $form = new static($container);
+    $form->setStringTranslation($container->get('string_translation'));
+    $form->setMessenger($container->get('messenger'));
+    return $form;
+  }
+
   /**
    * {@inheritdoc}
    */
@@ -204,8 +217,7 @@ public function prevSubmit(array $form, FormStateInterface $form_state) {
    * Save away the current information.
    */
   public function submitForm(array &$form, FormStateInterface $form_state) {
-
-    $messenger = \Drupal::messenger();
+    $messenger = $this->messenger();
     $messenger->addMessage($this->t('Your information has been submitted:'));
     $messenger->addMessage($this->t('Name: @name', ['@name' => $form_state->getValue(['step1', 'name'])]));
     $messenger->addMessage($this->t('Address: @address', ['@address' => $form_state->getValue(['step2', 'address'])]));

cron_example/src/Form/CronExampleForm.php

@@ -94,11 +94,11 @@ public function buildForm(array $form, FormStateInterface $form_state) {
       '#markup' => $this->t('The cron example demonstrates hook_cron() and hook_queue_info() processing. If you have administrative privileges you can run cron from this page and see the results.'),
     ];
 
-    $next_execution = \Drupal::state()->get('cron_example.next_execution');
+    $next_execution = $this->state->get('cron_example.next_execution');
     $next_execution = !empty($next_execution) ? $next_execution : REQUEST_TIME;
 
     $args = [
-      '%time' => date_iso8601(\Drupal::state()->get('cron_example.next_execution')),
+      '%time' => date_iso8601($this->state->get('cron_example.next_execution')),
       '%seconds' => $next_execution - REQUEST_TIME,
     ];
     $form['status']['last'] = [
@@ -193,7 +193,7 @@ public function cronRun(array &$form, FormStateInterface &$form_state) {
 
     $cron_reset = $form_state->getValue('cron_reset');
     if (!empty($cron_reset)) {
-      \Drupal::state()->set('cron_example.next_execution', 0);
+      $this->state->set('cron_example.next_execution', 0);
     }
 
     // Use a state variable to signal that cron was run manually from this form.