How to set default value for entity reference programmatically in a form?

Question

I have a custom form that I created programmatically.

    $target_type = 'node';
    $selection_handler = 'default';

    $selection_settings = ['page'];
    $data = serialize($selection_settings) . $target_type . $selection_handler;
    $selection_settings_key = Crypt::hmacBase64($data, Settings::getHashSalt());

    $key_value_storage = \Drupal::keyValue('entity_autocomplete');
    if (!$key_value_storage->has($selection_settings_key)) {
      $key_value_storage->set($selection_settings_key, $selection_settings);
    }


    $form['terms_default_node'] = [
      '#type' => 'textfield',
      '#title' => $this->t('Terms of Business - default page'),
      '#autocomplete_route_name' => 'system.entity_autocomplete',
      '#autocomplete_route_parameters' => [
        'target_type' => $target_type,
        'selection_handler' => $selection_handler,
        'selection_settings_key' => $selection_settings_key,
      ],
      '#default_value' =>  \Drupal\node\Entity\Node::load(1)->value, // What do I put here?
    ];

I don't get how to make the default value of the field be "Terms of Business (1)".

Autocomplete works, saving works, but I don't know how to recall that saved value again and make it as default_value when I open this form again.

This field doesn't have any widgets, etc. And I can't find anything in Google

Answer 1

This whole approach of entity autocomplete is not okay. Here is the correct way, and also it accepts Node Object as the default value well.

    $form['terms_default_node'] = [
      '#title' => $this->t('Terms of Business - default page'),
      '#type' => 'entity_autocomplete',
      '#target_type' => 'node',
      '#selection_handler' => 'default',
      '#selection_settings' => [
        'target_bundles' => ['article', 'page'],
      ],
      '#default_value' => $this->entityTypeManager->getStorage('node')->load($id), // Dependency injection.
    ];