TextItemBase.php

<?php

namespace Drupal\text\Plugin\Field\FieldType;

use Drupal\Component\Utility\Random;
use Drupal\Core\Field\FieldDefinitionInterface;
use Drupal\Core\Field\FieldItemBase;
use Drupal\Core\Field\FieldStorageDefinitionInterface;
use Drupal\Core\TypedData\DataDefinition;

/**
 * Base class for 'text' configurable field types.
 */
abstract class TextItemBase extends FieldItemBase {
    
    /**
     * {@inheritdoc}
     */
    public static function propertyDefinitions(FieldStorageDefinitionInterface $field_definition) {
        $properties['value'] = DataDefinition::create('string')->setLabel(t('Text'))
            ->setRequired(TRUE);
        $properties['format'] = DataDefinition::create('filter_format')->setLabel(t('Text format'));
        $properties['processed'] = DataDefinition::create('string')->setLabel(t('Processed text'))
            ->setDescription(t('The text with the text format applied.'))
            ->setComputed(TRUE)
            ->setClass('\\Drupal\\text\\TextProcessed')
            ->setSetting('text source', 'value')
            ->setInternal(FALSE);
        return $properties;
    }
    
    /**
     * {@inheritdoc}
     */
    public function applyDefaultValue($notify = TRUE) {
        // @todo: Add in the filter default format here.
        $this->setValue([
            'format' => NULL,
        ], $notify);
        return $this;
    }
    
    /**
     * {@inheritdoc}
     */
    public function isEmpty() {
        $value = $this->get('value')
            ->getValue();
        return $value === NULL || $value === '';
    }
    
    /**
     * {@inheritdoc}
     */
    public function onChange($property_name, $notify = TRUE) {
        // Unset processed properties that are affected by the change.
        foreach ($this->definition
            ->getPropertyDefinitions() as $property => $definition) {
            if ($definition->getClass() == '\\Drupal\\text\\TextProcessed') {
                if ($property_name == 'format' || $definition->getSetting('text source') == $property_name) {
                    $this->writePropertyValue($property, NULL);
                }
            }
        }
        parent::onChange($property_name, $notify);
    }
    
    /**
     * {@inheritdoc}
     */
    public static function generateSampleValue(FieldDefinitionInterface $field_definition) {
        $random = new Random();
        $settings = $field_definition->getSettings();
        if (empty($settings['max_length'])) {
            // Textarea handling
            $value = $random->paragraphs();
        }
        else {
            // Textfield handling.
            $value = substr($random->sentences(mt_rand(1, $settings['max_length'] / 3), FALSE), 0, $settings['max_length']);
        }
        $values = [
            'value' => $value,
            'summary' => $value,
            'format' => filter_fallback_format(),
        ];
        return $values;
    }

}