TestItem.php

<?php

namespace Drupal\field_test\Plugin\Field\FieldType;

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

/**
 * Defines the 'test_field' entity field item.
 *
 * @FieldType(
 *   id = "test_field",
 *   label = @Translation("Test field"),
 *   description = @Translation("Dummy field type used for tests."),
 *   default_widget = "test_field_widget",
 *   default_formatter = "field_test_default"
 * )
 */
class TestItem extends FieldItemBase {
    
    /**
     * {@inheritdoc}
     */
    public static function defaultStorageSettings() {
        return [
            'test_field_storage_setting' => 'dummy test string',
            'changeable' => 'a changeable field storage setting',
            'unchangeable' => 'an unchangeable field storage setting',
            'translatable_storage_setting' => 'a translatable field storage setting',
        ] + parent::defaultStorageSettings();
    }
    
    /**
     * {@inheritdoc}
     */
    public static function defaultFieldSettings() {
        return [
            'test_field_setting' => 'dummy test string',
            'translatable_field_setting' => 'a translatable field setting',
        ] + parent::defaultFieldSettings();
    }
    
    /**
     * {@inheritdoc}
     */
    public static function propertyDefinitions(FieldStorageDefinitionInterface $field_definition) {
        $properties['value'] = DataDefinition::create('integer')->setLabel(t('Test integer value'))
            ->setRequired(TRUE);
        return $properties;
    }
    
    /**
     * {@inheritdoc}
     */
    public static function schema(FieldStorageDefinitionInterface $field_definition) {
        return [
            'columns' => [
                'value' => [
                    'type' => 'int',
                    'size' => 'medium',
                ],
            ],
            'indexes' => [
                'value' => [
                    'value',
                ],
            ],
        ];
    }
    
    /**
     * {@inheritdoc}
     */
    public function storageSettingsForm(array &$form, FormStateInterface $form_state, $has_data) {
        $form['test_field_storage_setting'] = [
            '#type' => 'textfield',
            '#title' => t('Field test field storage setting'),
            '#default_value' => $this->getSetting('test_field_storage_setting'),
            '#required' => FALSE,
            '#description' => t('A dummy form element to simulate field storage setting.'),
        ];
        return $form;
    }
    
    /**
     * {@inheritdoc}
     */
    public function fieldSettingsForm(array $form, FormStateInterface $form_state) {
        $form['test_field_setting'] = [
            '#type' => 'textfield',
            '#title' => t('Field test field setting'),
            '#default_value' => $this->getSetting('test_field_setting'),
            '#required' => FALSE,
            '#description' => t('A dummy form element to simulate field setting.'),
        ];
        return $form;
    }
    
    /**
     * {@inheritdoc}
     */
    public function delete() {
        // Reports that delete() method is executed for testing purposes.
        field_test_memorize('field_test_field_delete', [
            $this->getEntity(),
        ]);
    }
    
    /**
     * {@inheritdoc}
     */
    public function getConstraints() {
        $constraint_manager = \Drupal::typedDataManager()->getValidationConstraintManager();
        $constraints = parent::getConstraints();
        $constraints[] = $constraint_manager->create('ComplexData', [
            'value' => [
                'TestField' => [
                    'value' => -1,
                    'message' => t('%name does not accept the value @value.', [
                        '%name' => $this->getFieldDefinition()
                            ->getLabel(),
                        '@value' => -1,
                    ]),
                ],
            ],
        ]);
        return $constraints;
    }
    
    /**
     * {@inheritdoc}
     */
    public function isEmpty() {
        return empty($this->value);
    }
    
    /**
     * {@inheritdoc}
     */
    public static function storageSettingsToConfigData(array $settings) {
        $settings['config_data_from_storage_setting'] = 'TRUE';
        unset($settings['storage_setting_from_config_data']);
        return $settings;
    }
    
    /**
     * {@inheritdoc}
     */
    public static function storageSettingsFromConfigData(array $settings) {
        $settings['storage_setting_from_config_data'] = 'TRUE';
        unset($settings['config_data_from_storage_setting']);
        return $settings;
    }
    
    /**
     * {@inheritdoc}
     */
    public static function fieldSettingsToConfigData(array $settings) {
        $settings['config_data_from_field_setting'] = 'TRUE';
        unset($settings['field_setting_from_config_data']);
        return $settings;
    }
    
    /**
     * {@inheritdoc}
     */
    public static function fieldSettingsFromConfigData(array $settings) {
        $settings['field_setting_from_config_data'] = 'TRUE';
        unset($settings['config_data_from_field_setting']);
        return $settings;
    }

}