1<?php 2 3namespace Drupal\Core\Render\Element; 4 5use Drupal\Core\Form\FormStateInterface; 6use Drupal\Component\Utility\Html as HtmlUtility; 7 8/** 9 * Provides a form element for a set of radio buttons. 10 * 11 * Properties: 12 * - #options: An associative array, where the keys are the returned values for 13 * each radio button, and the values are the labels next to each radio button. 14 * 15 * Usage example: 16 * @code 17 * $form['settings']['active'] = array( 18 * '#type' => 'radios', 19 * '#title' => $this->t('Poll status'), 20 * '#default_value' => 1, 21 * '#options' => array(0 => $this->t('Closed'), 1 => $this->t('Active')), 22 * ); 23 * @endcode 24 * 25 * @see \Drupal\Core\Render\Element\Checkboxes 26 * @see \Drupal\Core\Render\Element\Radio 27 * @see \Drupal\Core\Render\Element\Select 28 * 29 * @FormElement("radios") 30 */ 31class Radios extends FormElement { 32 33 use CompositeFormElementTrait; 34 35 /** 36 * {@inheritdoc} 37 */ 38 public function getInfo() { 39 $class = get_class($this); 40 return [ 41 '#input' => TRUE, 42 '#process' => [ 43 [$class, 'processRadios'], 44 ], 45 '#theme_wrappers' => ['radios'], 46 '#pre_render' => [ 47 [$class, 'preRenderCompositeFormElement'], 48 ], 49 ]; 50 } 51 52 /** 53 * Expands a radios element into individual radio elements. 54 */ 55 public static function processRadios(&$element, FormStateInterface $form_state, &$complete_form) { 56 if (count($element['#options']) > 0) { 57 $weight = 0; 58 foreach ($element['#options'] as $key => $choice) { 59 // Maintain order of options as defined in #options, in case the element 60 // defines custom option sub-elements, but does not define all option 61 // sub-elements. 62 $weight += 0.001; 63 64 $element += [$key => []]; 65 // Generate the parents as the autogenerator does, so we will have a 66 // unique id for each radio button. 67 $parents_for_id = array_merge($element['#parents'], [$key]); 68 $element[$key] += [ 69 '#type' => 'radio', 70 '#title' => $choice, 71 // The key is sanitized in Drupal\Core\Template\Attribute during output 72 // from the theme function. 73 '#return_value' => $key, 74 // Use default or FALSE. A value of FALSE means that the radio button is 75 // not 'checked'. 76 '#default_value' => isset($element['#default_value']) ? $element['#default_value'] : FALSE, 77 '#attributes' => $element['#attributes'], 78 '#parents' => $element['#parents'], 79 '#id' => HtmlUtility::getUniqueId('edit-' . implode('-', $parents_for_id)), 80 '#ajax' => isset($element['#ajax']) ? $element['#ajax'] : NULL, 81 // Errors should only be shown on the parent radios element. 82 '#error_no_message' => TRUE, 83 '#weight' => $weight, 84 ]; 85 } 86 } 87 return $element; 88 } 89 90 /** 91 * {@inheritdoc} 92 */ 93 public static function valueCallback(&$element, $input, FormStateInterface $form_state) { 94 if ($input !== FALSE) { 95 // When there's user input (including NULL), return it as the value. 96 // However, if NULL is submitted, FormBuilder::handleInputElement() will 97 // apply the default value, and we want that validated against #options 98 // unless it's empty. (An empty #default_value, such as NULL or FALSE, can 99 // be used to indicate that no radio button is selected by default.) 100 if (!isset($input) && !empty($element['#default_value'])) { 101 $element['#needs_validation'] = TRUE; 102 } 103 return $input; 104 } 105 else { 106 // For default value handling, simply return #default_value. Additionally, 107 // for a NULL default value, set #has_garbage_value to prevent 108 // FormBuilder::handleInputElement() converting the NULL to an empty 109 // string, so that code can distinguish between nothing selected and the 110 // selection of a radio button whose value is an empty string. 111 $value = isset($element['#default_value']) ? $element['#default_value'] : NULL; 112 if (!isset($value)) { 113 $element['#has_garbage_value'] = TRUE; 114 } 115 return $value; 116 } 117 } 118 119} 120