Tel.php

<?php

namespace Drupal\Core\Render\Element;

use Drupal\Core\Render\Attribute\FormElement;
use Drupal\Core\Render\Element;

/**
 * Provides a form element for entering a telephone number.
 *
 * Provides an HTML5 input element with type of "tel". It provides no special
 * validation.
 *
 * Properties:
 * - #size: The size of the input element in characters.
 * - #pattern: A string for the native HTML5 pattern attribute.
 *
 * Usage example:
 * @code
 * $form['phone'] = [
 *   '#type' => 'tel',
 *   '#title' => $this->t('Phone'),
 *   '#pattern' => '[^\d]*',
 * ];
 * @endcode
 *
 * @see \Drupal\Core\Render\Element
 */
class Tel extends FormElementBase {
    
    /**
     * {@inheritdoc}
     */
    public function getInfo() {
        $class = static::class;
        return [
            '#input' => TRUE,
            '#size' => 30,
            '#maxlength' => 128,
            '#autocomplete_route_name' => FALSE,
            '#process' => [
                [
                    $class,
                    'processAutocomplete',
                ],
                [
                    $class,
                    'processAjaxForm',
                ],
                [
                    $class,
                    'processPattern',
                ],
            ],
            '#pre_render' => [
                [
                    $class,
                    'preRenderTel',
                ],
            ],
            '#theme' => 'input__tel',
            '#theme_wrappers' => [
                'form_element',
            ],
        ];
    }
    
    /**
     * Prepares a #type 'tel' render element for input.html.twig.
     *
     * @param array $element
     *   An associative array containing the properties of the element.
     *   Properties used: #title, #value, #description, #size, #maxlength,
     *   #placeholder, #required, #attributes.
     *
     * @return array
     *   The $element with prepared variables ready for input.html.twig.
     */
    public static function preRenderTel($element) {
        $element['#attributes']['type'] = 'tel';
        Element::setAttributes($element, [
            'id',
            'name',
            'value',
            'size',
            'maxlength',
            'placeholder',
        ]);
        static::setAttributes($element, [
            'form-tel',
        ]);
        return $element;
    }

}