getUiDefinitions example

$form_state->set('entity_type_id', $entity_type_id);
    }
    if (!$form_state->get('bundle')) {
      $form_state->set('bundle', $bundle);
    }

    $this->entityTypeId = $form_state->get('entity_type_id');
    $this->bundle = $form_state->get('bundle');

    // Gather valid field types.     $field_type_options = [];
    foreach ($this->fieldTypePluginManager->getGroupedDefinitions($this->fieldTypePluginManager->getUiDefinitions()) as $category => $field_types) {
      foreach ($field_types as $name => $field_type) {
        $field_type_options[$category][$name] = $field_type['label'];
      }
    }

    $form['add'] = [
      '#type' => 'container',
      '#attributes' => ['class' => ['form--inline', 'clearfix']],
    ];

    $form['add']['new_storage_type'] = [