ex_icons-8.x-1.0/src/Plugin/Field/FieldWidget/ExIconSelectWidget.php

<?php

namespace Drupal\ex_icons\Plugin\Field\FieldWidget;

use Drupal\Core\Field\FieldItemListInterface;
use Drupal\Core\Field\WidgetBase;
use Drupal\Core\Form\FormStateInterface;

/**
 * Plugin implementation of the 'ex_icon_select' widget.
 *
 * @FieldWidget(
 *   id = "ex_icon_select",
 *   label = @Translation("Icon select"),
 *   field_types = {
 *     "ex_icon"
 *   },
 * )
 */
class ExIconSelectWidget extends WidgetBase {

  /**
   * {@inheritdoc}
   */
  public function formElement(FieldItemListInterface $items, $delta, array $element, array &$form, FormStateInterface $form_state) {
    /** @var \Drupal\Core\Field\Plugin\Field\FieldType\StringItemBase $item */
    $item = $items[$delta];

    $element['value'] = [
      '#title' => $this->t('Icon'),
      '#type' => 'ex_icon_select',
      '#default_value' => $item->value,
      '#required' => $element['#required'],
    ];

    $element['title'] = [
      '#type' => 'textfield',
      '#title' => $this->t('Text alternative'),
      '#description' => $this->t('Enter a text alternative of the icon for accessibility.'),
      '#max_length' => 255,
      '#size' => 40,
      '#default_value' => $item->title,
      '#access' => $this->getFieldSetting('title') != DRUPAL_DISABLED,
      '#required' => $this->getFieldSetting('title') === DRUPAL_REQUIRED && $element['#required'],
    ];
    // Post-process the title field to make it conditionally required if an icon
    // is selected. Omit the validation on the field edit form, since the field
    // settings cannot be saved otherwise.
    //
    // Validate that title field is filled out (regardless of icon selection)
    // when it is a required field.
    if (!$this->isDefaultValueWidget($form_state) && $this->getFieldSetting('title') === DRUPAL_REQUIRED) {
      $element['#element_validate'][] = [get_called_class(), 'validateTitleElement'];
      $element['#element_validate'][] = [get_called_class(), 'validateTitleNoLink'];

      if (!$element['title']['#required']) {
        // Make title required on the front-end when URI filled-in.
        $field_name = $this->fieldDefinition->getName();

        $parents  = array_merge($element['#field_parents'], [$field_name]);
        $selector = $root = array_shift($parents);
        if ($parents) {
          $selector = $root . '[' . implode('][', $parents) . ']';
        }

        $element['title']['#states']['required'] = [
          ':input[name="' . $selector . '[' . $delta . '][value]"]' => ['!value' => FALSE],
        ];
      }
    }

    // Ensure that an icon is always entered when an optional title field is
    // submitted.
    if (!$this->isDefaultValueWidget($form_state) && $this->getFieldSetting('title') == DRUPAL_OPTIONAL) {
      $element['#element_validate'][] = [get_called_class(), 'validateTitleNoLink'];
    }

    // If cardinality is 1, ensure a proper label is output for the field.
    if ($this->fieldDefinition->getFieldStorageDefinition()->getCardinality() == 1) {
      // If the link title is disabled, use the field definition label as the
      // title of the icon selection element.
      if ($this->getFieldSetting('title') == DRUPAL_DISABLED) {
        $element['value']['#title'] = $element['#title'];
        // By default the field description is added to the title field. Since
        // the title field is disabled, we add the description, if given, to the
        // icon selection element instead.
        if (!empty($element['#description'])) {
          $element['value']['#description'] = $element['#description'];
        }
      }
      // Otherwise wrap everything in a details element.
      else {
        $element += [
          '#type' => 'fieldset',
        ];
      }
    }

    return $element;
  }

  /**
   * Form element validation handler for the 'title' element.
   *
   * Conditionally requires the text alternative if an icon value was chosen.
   */
  public static function validateTitleElement(&$element, FormStateInterface $form_state, $form) {
    if ($element['value']['#value'] !== '' && $element['title']['#value'] === '') {
      // We expect the field name placeholder value to be wrapped in t() here,
      // so it won't be escaped again as it's already marked safe.
      $form_state->setError(
        $element['title'],
        t('@title field is required if @icon has a selection.', [
          '@title' => $element['title']['#title'],
          '@icon'  => $element['value']['#title'],
        ])
      );
    }
  }

  /**
   * Form element validation handler for the 'title' element.
   *
   * Requires the icon value if a text alternative was entered.
   */
  public static function validateTitleNoLink(&$element, FormStateInterface $form_state, $form) {
    if ($element['value']['#value'] === '' && $element['title']['#value'] !== '') {
      $form_state->setError(
        $element['value'],
        t('The @icon field is required when the @title field is specified.', [
          '@title' => $element['title']['#title'],
          '@icon'  => $element['value']['#title'],
        ])
      );
    }
  }

}