cms_content_sync-3.0.x-dev/modules/cms_content_sync_custom_field_example/src/Plugin/Field/FieldType/CustomField.php

<?php

namespace Drupal\cms_content_sync_custom_field_example\Plugin\Field\FieldType;

use Drupal\Core\Field\FieldItemBase;
use Drupal\Core\Field\FieldStorageDefinitionInterface;
use Drupal\Core\TypedData\DataDefinition;

/**
 * Plugin implementation of the 'CustomField' field type.
 *
 * @FieldType(
 *   id = "cs_custom_field",
 *   label = @Translation("Content Sync - Custom Field"),
 *   description = @Translation("Content Sync - Custom field."),
 *   default_widget = "cs_custom_field_widget",
 *   default_formatter = "cs_custom_field_formatter",
 * )
 */
class CustomField extends FieldItemBase {

  /**
   * {@inheritdoc}
   */
  public static function schema(FieldStorageDefinitionInterface $field) {
    return [
      'columns' => [
        'cs_text_field' => [
          'type' => 'text',
          'size' => 'big',
          'not null' => FALSE,
        ],
      ],
    ];
  }

  /**
   * {@inheritdoc}
   */
  public function isEmpty() {
    $value = $this->get('cs_text_field')->getValue();

    return NULL === $value || '' === $value;
  }

  /**
   * {@inheritdoc}
   */
  public static function propertyDefinitions(FieldStorageDefinitionInterface $field_definition) {
    $properties['cs_text_field'] = DataDefinition::create('string')
      ->setLabel(t('Content Sync - Text Field'));

    return $properties;
  }

}