function Element::children

Same name and namespace in other branches
  1. 9 core/lib/Drupal/Core/Render/Element.php \Drupal\Core\Render\Element::children()
  2. 8.9.x core/lib/Drupal/Core/Render/Element.php \Drupal\Core\Render\Element::children()
  3. 10 core/lib/Drupal/Core/Render/Element.php \Drupal\Core\Render\Element::children()

Identifies the children of an element array, optionally sorted by weight.

The children of an element array are those key/value pairs whose key does not start with a '#'. See \Drupal\Core\Render\RendererInterface::render() for details.

Parameters

array $elements: The element array whose children are to be identified. Passed by reference.

bool $sort: Boolean to indicate whether the children should be sorted by weight.

Return value

array The array keys of the element's children.

116 calls to Element::children()
AccountSettingsForm::buildForm in core/modules/user/src/AccountSettingsForm.php
Form constructor.
Actions::preRenderActionsDropbutton in core/lib/Drupal/Core/Render/Element/Actions.php
#pre_render callback for #type 'actions'.
AddFormBase::preRenderAddedMedia in core/modules/media_library/src/Form/AddFormBase.php
Converts the set of newly added media into an item list for rendering.
ArgumentPluginBase::preRenderMoveArgumentOptions in core/modules/views/src/Plugin/views/argument/ArgumentPluginBase.php
Moves argument options into their place.
BookAdminEditForm::submitForm in core/modules/book/src/Form/BookAdminEditForm.php
Form submission handler.

... See full list

File

core/lib/Drupal/Core/Render/Element.php, line 71

Class

Element
Provides helper methods for Drupal render elements.

Namespace

Drupal\Core\Render

Code

public static function children(array &$elements, $sort = FALSE) {
    // Do not attempt to sort elements which have already been sorted.
    $sort = isset($elements['#sorted']) ? !$elements['#sorted'] : $sort;
    // Filter out properties from the element, leaving only children.
    $count = count($elements);
    $child_weights = [];
    $i = 0;
    $sortable = FALSE;
    foreach ($elements as $key => $value) {
        if (is_int($key) || $key === '' || $key[0] !== '#') {
            if (is_array($value)) {
                if (isset($value['#weight'])) {
                    $weight = $value['#weight'];
                    $sortable = TRUE;
                }
                else {
                    $weight = 0;
                }
                // Supports weight with up to three digit precision and conserve
                // the insertion order.
                $child_weights[$key] = floor($weight * 1000) + $i / $count;
            }
            elseif (isset($value)) {
                throw new \InvalidArgumentException(sprintf('"%s" is an invalid render array key. Value should be an array but got a %s.', $key, gettype($value)));
            }
        }
        $i++;
    }
    // Sort the children if necessary.
    if ($sort && $sortable) {
        asort($child_weights);
        // Put the sorted children back into $elements in the correct order, to
        // preserve sorting if the same element is passed through
        // \Drupal\Core\Render\Element::children() twice.
        foreach ($child_weights as $key => $weight) {
            $value = $elements[$key];
            unset($elements[$key]);
            $elements[$key] = $value;
        }
        $elements['#sorted'] = TRUE;
    }
    return array_keys($child_weights);
}

Buggy or inaccurate documentation? Please file an issue. Need support? Need help programming? Connect with the Drupal community.