field_ui.admin.inc

Administrative interface for custom field type creation.

File

modules/field_ui/field_ui.admin.inc

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<?php


/**
 * @file
 * Administrative interface for custom field type creation.
 */

/**
 * Menu callback; lists all defined fields for quick reference.
 */
function field_ui_fields_list() {
    $instances = field_info_instances();
    $field_types = field_info_field_types();
    $bundles = field_info_bundles();
    $modules = system_rebuild_module_data();
    $header = array(
        t('Field name'),
        t('Field type'),
        t('Used in'),
    );
    $rows = array();
    foreach ($instances as $entity_type => $type_bundles) {
        foreach ($type_bundles as $bundle => $bundle_instances) {
            foreach ($bundle_instances as $field_name => $instance) {
                $field = field_info_field($field_name);
                // Initialize the row if we encounter the field for the first time.
                if (!isset($rows[$field_name])) {
                    $rows[$field_name]['class'] = $field['locked'] ? array(
                        'menu-disabled',
                    ) : array(
                        '',
                    );
                    $rows[$field_name]['data'][0] = $field['locked'] ? t('@field_name (Locked)', array(
                        '@field_name' => $field_name,
                    )) : $field_name;
                    $module_name = $field_types[$field['type']]['module'];
                    $rows[$field_name]['data'][1] = $field_types[$field['type']]['label'] . ' ' . t('(module: !module)', array(
                        '!module' => $modules[$module_name]->info['name'],
                    ));
                }
                // Add the current instance.
                $admin_path = _field_ui_bundle_admin_path($entity_type, $bundle);
                $rows[$field_name]['data'][2][] = $admin_path ? l($bundles[$entity_type][$bundle]['label'], $admin_path . '/fields') : $bundles[$entity_type][$bundle]['label'];
            }
        }
    }
    foreach ($rows as $field_name => $cell) {
        $rows[$field_name]['data'][2] = implode(', ', $cell['data'][2]);
    }
    if (empty($rows)) {
        $output = t('No fields have been defined yet.');
    }
    else {
        // Sort rows by field name.
        ksort($rows);
        $output = theme('table', array(
            'header' => $header,
            'rows' => $rows,
        ));
    }
    return $output;
}

/**
 * Displays a message listing the inactive fields of a given bundle.
 */
function field_ui_inactive_message($entity_type, $bundle) {
    $inactive_instances = field_ui_inactive_instances($entity_type, $bundle);
    if (!empty($inactive_instances)) {
        $field_types = field_info_field_types();
        $widget_types = field_info_widget_types();
        foreach ($inactive_instances as $field_name => $instance) {
            $list[] = t('%field (@field_name) field requires the %widget_type widget provided by %widget_module module', array(
                '%field' => $instance['label'],
                '@field_name' => $instance['field_name'],
                '%widget_type' => isset($widget_types[$instance['widget']['type']]) ? $widget_types[$instance['widget']['type']]['label'] : $instance['widget']['type'],
                '%widget_module' => $instance['widget']['module'],
            ));
        }
        drupal_set_message(t('Inactive fields are not shown unless their providing modules are enabled. The following fields are not enabled: !list', array(
            '!list' => theme('item_list', array(
                'items' => $list,
            )),
        )), 'error');
    }
}

/**
 * Determines the rendering order of an array representing a tree.
 *
 * Callback for array_reduce() within field_ui_table_pre_render().
 */
function _field_ui_reduce_order($array, $a) {
    $array = !isset($array) ? array() : $array;
    if ($a['name']) {
        $array[] = $a['name'];
    }
    if (!empty($a['children'])) {
        uasort($a['children'], 'drupal_sort_weight');
        $array = array_merge($array, array_reduce($a['children'], '_field_ui_reduce_order'));
    }
    return $array;
}

/**
 * Returns the region to which a row in the 'Manage fields' screen belongs.
 *
 * This function is used as a #region_callback in
 * field_ui_field_overview_form(). It is called during
 * field_ui_table_pre_render().
 */
function field_ui_field_overview_row_region($row) {
    switch ($row['#row_type']) {
        case 'field':
        case 'extra_field':
            return 'main';
        case 'add_new_field':
            // If no input in 'label', assume the row has not been dragged out of the
            // 'add new' section.
            return !empty($row['label']['#value']) ? 'main' : 'add_new';
    }
}

/**
 * Returns the region to which a row in the 'Manage display' screen belongs.
 *
 * This function is used as a #region_callback in
 * field_ui_field_overview_form(), and is called during
 * field_ui_table_pre_render().
 */
function field_ui_display_overview_row_region($row) {
    switch ($row['#row_type']) {
        case 'field':
        case 'extra_field':
            return $row['format']['type']['#value'] == 'hidden' ? 'hidden' : 'visible';
    }
}

/**
 * Pre-render callback for field_ui_table elements.
 */
function field_ui_table_pre_render($elements) {
    $js_settings = array();
    // For each region, build the tree structure from the weight and parenting
    // data contained in the flat form structure, to determine row order and
    // indentation.
    $regions = $elements['#regions'];
    $tree = array(
        '' => array(
            'name' => '',
            'children' => array(),
        ),
    );
    $trees = array_fill_keys(array_keys($regions), $tree);
    $parents = array();
    $list = drupal_map_assoc(element_children($elements));
    // Iterate on rows until we can build a known tree path for all of them.
    while ($list) {
        foreach ($list as $name) {
            $row =& $elements[$name];
            $parent = $row['parent_wrapper']['parent']['#value'];
            // Proceed if parent is known.
            if (empty($parent) || isset($parents[$parent])) {
                // Grab parent, and remove the row from the next iteration.
                $parents[$name] = $parent ? array_merge($parents[$parent], array(
                    $parent,
                )) : array();
                unset($list[$name]);
                // Determine the region for the row.
                $function = $row['#region_callback'];
                $region_name = $function($row);
                // Add the element in the tree.
                $target =& $trees[$region_name][''];
                foreach ($parents[$name] as $key) {
                    $target =& $target['children'][$key];
                }
                $target['children'][$name] = array(
                    'name' => $name,
                    'weight' => $row['weight']['#value'],
                );
                // Add tabledrag indentation to the first row cell.
                if ($depth = count($parents[$name])) {
                    $children = element_children($row);
                    $cell = current($children);
                    $row[$cell]['#prefix'] = theme('indentation', array(
                        'size' => $depth,
                    )) . (isset($row[$cell]['#prefix']) ? $row[$cell]['#prefix'] : '');
                }
                // Add row id and associate JS settings.
                $id = drupal_html_class($name);
                $row['#attributes']['id'] = $id;
                if (isset($row['#js_settings'])) {
                    $row['#js_settings'] += array(
                        'rowHandler' => $row['#row_type'],
                        'name' => $name,
                        'region' => $region_name,
                    );
                    $js_settings[$id] = $row['#js_settings'];
                }
            }
        }
    }
    // Determine rendering order from the tree structure.
    foreach ($regions as $region_name => $region) {
        $elements['#regions'][$region_name]['rows_order'] = array_reduce($trees[$region_name], '_field_ui_reduce_order');
    }
    $elements['#attached']['js'][] = array(
        'type' => 'setting',
        'data' => array(
            'fieldUIRowsData' => $js_settings,
        ),
    );
    return $elements;
}

/**
 * Returns HTML for Field UI overview tables.
 *
 * @param $variables
 *   An associative array containing:
 *   - elements: An associative array containing a Form API structure to be
 *     rendered as a table.
 *
 * @ingroup themeable
 */
function theme_field_ui_table($variables) {
    $elements = $variables['elements'];
    $table = array();
    $js_settings = array();
    // Add table headers and attributes.
    foreach (array(
        'header',
        'attributes',
    ) as $key) {
        if (isset($elements["#{$key}"])) {
            $table[$key] = $elements["#{$key}"];
        }
    }
    // Determine the colspan to use for region rows, by checking the number of
    // columns in the headers.
    $columns_count = 0;
    foreach ($table['header'] as $header) {
        $columns_count += is_array($header) && isset($header['colspan']) ? $header['colspan'] : 1;
    }
    // Render rows, region by region.
    foreach ($elements['#regions'] as $region_name => $region) {
        $region_name_class = drupal_html_class($region_name);
        // Add region rows.
        if (isset($region['title'])) {
            $table['rows'][] = array(
                'class' => array(
                    'region-title',
                    'region-' . $region_name_class . '-title',
                ),
                'no_striping' => TRUE,
                'data' => array(
                    array(
                        'data' => $region['title'],
                        'colspan' => $columns_count,
                    ),
                ),
            );
        }
        if (isset($region['message'])) {
            $class = empty($region['rows_order']) ? 'region-empty' : 'region-populated';
            $table['rows'][] = array(
                'class' => array(
                    'region-message',
                    'region-' . $region_name_class . '-message',
                    $class,
                ),
                'no_striping' => TRUE,
                'data' => array(
                    array(
                        'data' => $region['message'],
                        'colspan' => $columns_count,
                    ),
                ),
            );
        }
        // Add form rows, in the order determined at pre-render time.
        foreach ($region['rows_order'] as $name) {
            $element = $elements[$name];
            $row = array(
                'data' => array(),
            );
            if (isset($element['#attributes'])) {
                $row += $element['#attributes'];
            }
            // Render children as table cells.
            foreach (element_children($element) as $cell_key) {
                $child =& $element[$cell_key];
                // Do not render a cell for children of #type 'value'.
                if (!(isset($child['#type']) && $child['#type'] == 'value')) {
                    $cell = array(
                        'data' => drupal_render($child),
                    );
                    if (isset($child['#cell_attributes'])) {
                        $cell += $child['#cell_attributes'];
                    }
                    $row['data'][] = $cell;
                }
            }
            $table['rows'][] = $row;
        }
    }
    return theme('table', $table);
}

/**
 * Form constructor for the 'Manage fields' form of a bundle.
 *
 * Allows fields and pseudo-fields to be re-ordered.
 *
 * @see field_ui_field_overview_form_validate()
 * @see field_ui_field_overview_form_submit()
 * @ingroup forms
 */
function field_ui_field_overview_form($form, &$form_state, $entity_type, $bundle) {
    $bundle = field_extract_bundle($entity_type, $bundle);
    field_ui_inactive_message($entity_type, $bundle);
    $admin_path = _field_ui_bundle_admin_path($entity_type, $bundle);
    // When displaying the form, make sure the list of fields is up-to-date.
    if (empty($form_state['post'])) {
        field_info_cache_clear();
    }
    // Gather bundle information.
    $instances = field_info_instances($entity_type, $bundle);
    $field_types = field_info_field_types();
    $widget_types = field_info_widget_types();
    $extra_fields = field_info_extra_fields($entity_type, $bundle, 'form');
    $form += array(
        '#entity_type' => $entity_type,
        '#bundle' => $bundle,
        '#fields' => array_keys($instances),
        '#extra' => array_keys($extra_fields),
    );
    $table = array(
        '#type' => 'field_ui_table',
        '#tree' => TRUE,
        '#header' => array(
            t('Label'),
            t('Weight'),
            t('Parent'),
            t('Machine name'),
            t('Field type'),
            t('Widget'),
            array(
                'data' => t('Operations'),
                'colspan' => 2,
            ),
        ),
        '#parent_options' => array(),
        '#regions' => array(
            'main' => array(
                'message' => t('No fields are present yet.'),
            ),
            'add_new' => array(
                'title' => '&nbsp;',
            ),
        ),
        '#attributes' => array(
            'class' => array(
                'field-ui-overview',
            ),
            'id' => 'field-overview',
        ),
    );
    // Fields.
    foreach ($instances as $name => $instance) {
        $field = field_info_field($instance['field_name']);
        $admin_field_path = $admin_path . '/fields/' . $instance['field_name'];
        $table[$name] = array(
            '#attributes' => array(
                'class' => array(
                    'draggable',
                    'tabledrag-leaf',
                ),
            ),
            '#row_type' => 'field',
            '#region_callback' => 'field_ui_field_overview_row_region',
            'label' => array(
                '#markup' => check_plain($instance['label']),
            ),
            'weight' => array(
                '#type' => 'textfield',
                '#title' => t('Weight for @title', array(
                    '@title' => $instance['label'],
                )),
                '#title_display' => 'invisible',
                '#default_value' => $instance['widget']['weight'],
                '#size' => 3,
                '#attributes' => array(
                    'class' => array(
                        'field-weight',
                    ),
                ),
            ),
            'parent_wrapper' => array(
                'parent' => array(
                    '#type' => 'select',
                    '#title' => t('Parent for @title', array(
                        '@title' => $instance['label'],
                    )),
                    '#title_display' => 'invisible',
                    '#options' => $table['#parent_options'],
                    '#empty_value' => '',
                    '#attributes' => array(
                        'class' => array(
                            'field-parent',
                        ),
                    ),
                    '#parents' => array(
                        'fields',
                        $name,
                        'parent',
                    ),
                ),
                'hidden_name' => array(
                    '#type' => 'hidden',
                    '#default_value' => $name,
                    '#attributes' => array(
                        'class' => array(
                            'field-name',
                        ),
                    ),
                ),
            ),
            'field_name' => array(
                '#markup' => $instance['field_name'],
            ),
            'type' => array(
                '#type' => 'link',
                '#title' => t($field_types[$field['type']]['label']),
                '#href' => $admin_field_path . '/field-settings',
                '#options' => array(
                    'attributes' => array(
                        'title' => t('Edit field settings.'),
                    ),
                ),
            ),
            'widget_type' => array(
                '#type' => 'link',
                '#title' => t($widget_types[$instance['widget']['type']]['label']),
                '#href' => $admin_field_path . '/widget-type',
                '#options' => array(
                    'attributes' => array(
                        'title' => t('Change widget type.'),
                    ),
                ),
            ),
            'edit' => array(
                '#type' => 'link',
                '#title' => t('edit'),
                '#href' => $admin_field_path,
                '#options' => array(
                    'attributes' => array(
                        'title' => t('Edit instance settings.'),
                    ),
                ),
            ),
            'delete' => array(
                '#type' => 'link',
                '#title' => t('delete'),
                '#href' => $admin_field_path . '/delete',
                '#options' => array(
                    'attributes' => array(
                        'title' => t('Delete instance.'),
                    ),
                ),
            ),
        );
        if (!empty($instance['locked'])) {
            $table[$name]['edit'] = array(
                '#value' => t('Locked'),
            );
            $table[$name]['delete'] = array();
            $table[$name]['#attributes']['class'][] = 'menu-disabled';
        }
    }
    // Non-field elements.
    foreach ($extra_fields as $name => $extra_field) {
        $table[$name] = array(
            '#attributes' => array(
                'class' => array(
                    'draggable',
                    'tabledrag-leaf',
                ),
            ),
            '#row_type' => 'extra_field',
            '#region_callback' => 'field_ui_field_overview_row_region',
            'label' => array(
                '#markup' => check_plain($extra_field['label']),
            ),
            'weight' => array(
                '#type' => 'textfield',
                '#default_value' => $extra_field['weight'],
                '#size' => 3,
                '#attributes' => array(
                    'class' => array(
                        'field-weight',
                    ),
                ),
                '#title_display' => 'invisible',
                '#title' => t('Weight for @title', array(
                    '@title' => $extra_field['label'],
                )),
            ),
            'parent_wrapper' => array(
                'parent' => array(
                    '#type' => 'select',
                    '#title' => t('Parent for @title', array(
                        '@title' => $extra_field['label'],
                    )),
                    '#title_display' => 'invisible',
                    '#options' => $table['#parent_options'],
                    '#empty_value' => '',
                    '#attributes' => array(
                        'class' => array(
                            'field-parent',
                        ),
                    ),
                    '#parents' => array(
                        'fields',
                        $name,
                        'parent',
                    ),
                ),
                'hidden_name' => array(
                    '#type' => 'hidden',
                    '#default_value' => $name,
                    '#attributes' => array(
                        'class' => array(
                            'field-name',
                        ),
                    ),
                ),
            ),
            'field_name' => array(
                '#markup' => $name,
            ),
            'type' => array(
                '#markup' => isset($extra_field['description']) ? $extra_field['description'] : '',
                '#cell_attributes' => array(
                    'colspan' => 2,
                ),
            ),
            'edit' => array(
                '#markup' => isset($extra_field['edit']) ? $extra_field['edit'] : '',
            ),
            'delete' => array(
                '#markup' => isset($extra_field['delete']) ? $extra_field['delete'] : '',
            ),
        );
    }
    // Additional row: add new field.
    $max_weight = field_info_max_weight($entity_type, $bundle, 'form');
    $field_type_options = field_ui_field_type_options();
    $widget_type_options = field_ui_widget_type_options(NULL, TRUE);
    if ($field_type_options && $widget_type_options) {
        $name = '_add_new_field';
        $table[$name] = array(
            '#attributes' => array(
                'class' => array(
                    'draggable',
                    'tabledrag-leaf',
                    'add-new',
                ),
            ),
            '#row_type' => 'add_new_field',
            '#region_callback' => 'field_ui_field_overview_row_region',
            'label' => array(
                '#type' => 'textfield',
                '#title' => t('New field label'),
                '#title_display' => 'invisible',
                '#size' => 15,
                '#description' => t('Label'),
                '#prefix' => '<div class="label-input"><div class="add-new-placeholder">' . t('Add new field') . '</div>',
                '#suffix' => '</div>',
            ),
            'weight' => array(
                '#type' => 'textfield',
                '#default_value' => $max_weight + 1,
                '#size' => 3,
                '#title_display' => 'invisible',
                '#title' => t('Weight for new field'),
                '#attributes' => array(
                    'class' => array(
                        'field-weight',
                    ),
                ),
                '#prefix' => '<div class="add-new-placeholder">&nbsp;</div>',
            ),
            'parent_wrapper' => array(
                'parent' => array(
                    '#type' => 'select',
                    '#title' => t('Parent for new field'),
                    '#title_display' => 'invisible',
                    '#options' => $table['#parent_options'],
                    '#empty_value' => '',
                    '#attributes' => array(
                        'class' => array(
                            'field-parent',
                        ),
                    ),
                    '#prefix' => '<div class="add-new-placeholder">&nbsp;</div>',
                    '#parents' => array(
                        'fields',
                        $name,
                        'parent',
                    ),
                ),
                'hidden_name' => array(
                    '#type' => 'hidden',
                    '#default_value' => $name,
                    '#attributes' => array(
                        'class' => array(
                            'field-name',
                        ),
                    ),
                ),
            ),
            'field_name' => array(
                '#type' => 'machine_name',
                '#title' => t('New field name'),
                '#title_display' => 'invisible',
                // This field should stay LTR even for RTL languages.
'#field_prefix' => '<span dir="ltr">field_',
                '#field_suffix' => '</span>&lrm;',
                '#size' => 15,
                '#description' => t('A unique machine-readable name containing letters, numbers, and underscores.'),
                // 32 characters minus the 'field_' prefix.
'#maxlength' => 26,
                '#prefix' => '<div class="add-new-placeholder">&nbsp;</div>',
                '#machine_name' => array(
                    'source' => array(
                        'fields',
                        $name,
                        'label',
                    ),
                    'exists' => '_field_ui_field_name_exists',
                    'standalone' => TRUE,
                    'label' => '',
                ),
                '#required' => FALSE,
            ),
            'type' => array(
                '#type' => 'select',
                '#title' => t('Type of new field'),
                '#title_display' => 'invisible',
                '#options' => $field_type_options,
                '#empty_option' => t('- Select a field type -'),
                '#description' => t('Type of data to store.'),
                '#attributes' => array(
                    'class' => array(
                        'field-type-select',
                    ),
                ),
                '#prefix' => '<div class="add-new-placeholder">&nbsp;</div>',
            ),
            'widget_type' => array(
                '#type' => 'select',
                '#title' => t('Widget for new field'),
                '#title_display' => 'invisible',
                '#options' => $widget_type_options,
                '#empty_option' => t('- Select a widget -'),
                '#description' => t('Form element to edit the data.'),
                '#attributes' => array(
                    'class' => array(
                        'widget-type-select',
                    ),
                ),
                '#cell_attributes' => array(
                    'colspan' => 3,
                ),
                '#prefix' => '<div class="add-new-placeholder">&nbsp;</div>',
            ),
            // Place the 'translatable' property as an explicit value so that contrib
            // modules can form_alter() the value for newly created fields.
'translatable' => array(
                '#type' => 'value',
                '#value' => FALSE,
            ),
        );
    }
    // Additional row: add existing field.
    $existing_fields = field_ui_existing_field_options($entity_type, $bundle);
    if ($existing_fields && $widget_type_options) {
        // Build list of options.
        $existing_field_options = array();
        foreach ($existing_fields as $field_name => $info) {
            $text = t('@type: @field (@label)', array(
                '@type' => $info['type_label'],
                '@label' => $info['label'],
                '@field' => $info['field'],
            ));
            $existing_field_options[$field_name] = truncate_utf8($text, 80, FALSE, TRUE);
        }
        asort($existing_field_options);
        $name = '_add_existing_field';
        $table[$name] = array(
            '#attributes' => array(
                'class' => array(
                    'draggable',
                    'tabledrag-leaf',
                    'add-new',
                ),
            ),
            '#row_type' => 'add_new_field',
            '#region_callback' => 'field_ui_field_overview_row_region',
            'label' => array(
                '#type' => 'textfield',
                '#title' => t('Existing field label'),
                '#title_display' => 'invisible',
                '#size' => 15,
                '#description' => t('Label'),
                '#attributes' => array(
                    'class' => array(
                        'label-textfield',
                    ),
                ),
                '#prefix' => '<div class="label-input"><div class="add-new-placeholder">' . t('Add existing field') . '</div>',
                '#suffix' => '</div>',
            ),
            'weight' => array(
                '#type' => 'textfield',
                '#default_value' => $max_weight + 2,
                '#size' => 3,
                '#title_display' => 'invisible',
                '#title' => t('Weight for added field'),
                '#attributes' => array(
                    'class' => array(
                        'field-weight',
                    ),
                ),
                '#prefix' => '<div class="add-new-placeholder">&nbsp;</div>',
            ),
            'parent_wrapper' => array(
                'parent' => array(
                    '#type' => 'select',
                    '#title' => t('Parent for existing field'),
                    '#title_display' => 'invisible',
                    '#options' => $table['#parent_options'],
                    '#empty_value' => '',
                    '#attributes' => array(
                        'class' => array(
                            'field-parent',
                        ),
                    ),
                    '#prefix' => '<div class="add-new-placeholder">&nbsp;</div>',
                    '#parents' => array(
                        'fields',
                        $name,
                        'parent',
                    ),
                ),
                'hidden_name' => array(
                    '#type' => 'hidden',
                    '#default_value' => $name,
                    '#attributes' => array(
                        'class' => array(
                            'field-name',
                        ),
                    ),
                ),
            ),
            'field_name' => array(
                '#type' => 'select',
                '#title' => t('Existing field to share'),
                '#title_display' => 'invisible',
                '#options' => $existing_field_options,
                '#empty_option' => t('- Select an existing field -'),
                '#description' => t('Field to share'),
                '#attributes' => array(
                    'class' => array(
                        'field-select',
                    ),
                ),
                '#cell_attributes' => array(
                    'colspan' => 2,
                ),
                '#prefix' => '<div class="add-new-placeholder">&nbsp;</div>',
            ),
            'widget_type' => array(
                '#type' => 'select',
                '#title' => t('Widget for existing field'),
                '#title_display' => 'invisible',
                '#options' => $widget_type_options,
                '#empty_option' => t('- Select a widget -'),
                '#description' => t('Form element to edit the data.'),
                '#attributes' => array(
                    'class' => array(
                        'widget-type-select',
                    ),
                ),
                '#cell_attributes' => array(
                    'colspan' => 3,
                ),
                '#prefix' => '<div class="add-new-placeholder">&nbsp;</div>',
            ),
        );
    }
    $form['fields'] = $table;
    $form['actions'] = array(
        '#type' => 'actions',
    );
    $form['actions']['submit'] = array(
        '#type' => 'submit',
        '#value' => t('Save'),
    );
    $form['#attached']['css'][] = drupal_get_path('module', 'field_ui') . '/field_ui.css';
    $form['#attached']['js'][] = drupal_get_path('module', 'field_ui') . '/field_ui.js';
    // Add settings for the update selects behavior.
    $js_fields = array();
    foreach ($existing_fields as $field_name => $info) {
        $js_fields[$field_name] = array(
            'label' => $info['label'],
            'type' => $info['type'],
            'widget' => $info['widget_type'],
        );
    }
    $form['#attached']['js'][] = array(
        'type' => 'setting',
        'data' => array(
            'fields' => $js_fields,
            'fieldWidgetTypes' => field_ui_widget_type_options(),
        ),
    );
    // Add tabledrag behavior.
    $form['#attached']['drupal_add_tabledrag'][] = array(
        'field-overview',
        'order',
        'sibling',
        'field-weight',
    );
    $form['#attached']['drupal_add_tabledrag'][] = array(
        'field-overview',
        'match',
        'parent',
        'field-parent',
        'field-parent',
        'field-name',
    );
    return $form;
}

/**
 * Form validation handler for field_ui_field_overview_form().
 *
 * @see field_ui_field_overview_form_submit()
 */
function field_ui_field_overview_form_validate($form, &$form_state) {
    _field_ui_field_overview_form_validate_add_new($form, $form_state);
    _field_ui_field_overview_form_validate_add_existing($form, $form_state);
}

/**
 * Validates the 'add new field' row of field_ui_field_overview_form().
 *
 * @see field_ui_field_overview_form_validate()
 */
function _field_ui_field_overview_form_validate_add_new($form, &$form_state) {
    $field = $form_state['values']['fields']['_add_new_field'];
    // Validate if any information was provided in the 'add new field' row.
    if (array_filter(array(
        $field['label'],
        $field['field_name'],
        $field['type'],
        $field['widget_type'],
    ))) {
        // Missing label.
        if (!$field['label']) {
            form_set_error('fields][_add_new_field][label', t('Add new field: you need to provide a label.'));
        }
        // Missing field name.
        if (!$field['field_name']) {
            form_set_error('fields][_add_new_field][field_name', t('Add new field: you need to provide a field name.'));
        }
        else {
            $field_name = $field['field_name'];
            // Add the 'field_' prefix.
            $field_name = 'field_' . $field_name;
            form_set_value($form['fields']['_add_new_field']['field_name'], $field_name, $form_state);
        }
        // Missing field type.
        if (!$field['type']) {
            form_set_error('fields][_add_new_field][type', t('Add new field: you need to select a field type.'));
        }
        // Missing widget type.
        if (!$field['widget_type']) {
            form_set_error('fields][_add_new_field][widget_type', t('Add new field: you need to select a widget.'));
        }
        elseif ($field['type']) {
            $widget_types = field_ui_widget_type_options($field['type']);
            if (!isset($widget_types[$field['widget_type']])) {
                form_set_error('fields][_add_new_field][widget_type', t('Add new field: invalid widget.'));
            }
        }
    }
}

/**
 * Render API callback: Checks if a field machine name is taken.
 *
 * @param $value
 *   The machine name, not prefixed with 'field_'.
 *
 * @return
 *   Whether or not the field machine name is taken.
 */
function _field_ui_field_name_exists($value) {
    // Prefix with 'field_'.
    $field_name = 'field_' . $value;
    // We need to check inactive fields as well, so we can't use
    // field_info_fields().
    return (bool) field_read_fields(array(
        'field_name' => $field_name,
    ), array(
        'include_inactive' => TRUE,
    ));
}

/**
 * Validates the 'add existing field' row of field_ui_field_overview_form().
 *
 * @see field_ui_field_overview_form_validate()
 */
function _field_ui_field_overview_form_validate_add_existing($form, &$form_state) {
    // The form element might be absent if no existing fields can be added to
    // this bundle.
    if (isset($form_state['values']['fields']['_add_existing_field'])) {
        $field = $form_state['values']['fields']['_add_existing_field'];
        // Validate if any information was provided in the 'add existing field' row.
        if (array_filter(array(
            $field['label'],
            $field['field_name'],
            $field['widget_type'],
        ))) {
            // Missing label.
            if (!$field['label']) {
                form_set_error('fields][_add_existing_field][label', t('Add existing field: you need to provide a label.'));
            }
            // Missing existing field name.
            if (!$field['field_name']) {
                form_set_error('fields][_add_existing_field][field_name', t('Add existing field: you need to select a field.'));
            }
            // Missing widget type.
            if (!$field['widget_type']) {
                form_set_error('fields][_add_existing_field][widget_type', t('Add existing field: you need to select a widget.'));
            }
            elseif ($field['field_name'] && ($existing_field = field_info_field($field['field_name']))) {
                $widget_types = field_ui_widget_type_options($existing_field['type']);
                if (!isset($widget_types[$field['widget_type']])) {
                    form_set_error('fields][_add_existing_field][widget_type', t('Add existing field: invalid widget.'));
                }
            }
        }
    }
}

/**
 * Form submission handler for field_ui_field_overview_form().
 *
 * @see field_ui_field_overview_form_validate()
 */
function field_ui_field_overview_form_submit($form, &$form_state) {
    $form_values = $form_state['values']['fields'];
    $entity_type = $form['#entity_type'];
    $bundle = $form['#bundle'];
    $admin_path = _field_ui_bundle_admin_path($entity_type, $bundle);
    $bundle_settings = field_bundle_settings($entity_type, $bundle);
    // Update field weights.
    foreach ($form_values as $key => $values) {
        if (in_array($key, $form['#fields'])) {
            $instance = field_read_instance($entity_type, $key, $bundle);
            $instance['widget']['weight'] = $values['weight'];
            field_update_instance($instance);
        }
        elseif (in_array($key, $form['#extra'])) {
            $bundle_settings['extra_fields']['form'][$key]['weight'] = $values['weight'];
        }
    }
    field_bundle_settings($entity_type, $bundle, $bundle_settings);
    $destinations = array();
    // Check if the target entity uses a non numeric ID.
    $entity_info = entity_get_info($entity_type);
    if (!empty($entity_info['entity_id_type']) && $entity_info['entity_id_type'] === 'string') {
        $entity_id_type = 'string';
    }
    else {
        $entity_id_type = NULL;
    }
    // Create new field.
    $field = array();
    if (!empty($form_values['_add_new_field']['field_name'])) {
        $values = $form_values['_add_new_field'];
        $field = array(
            'field_name' => $values['field_name'],
            'type' => $values['type'],
            'translatable' => $values['translatable'],
            'entity_id_type' => $entity_id_type,
        );
        $instance = array(
            'field_name' => $field['field_name'],
            'entity_type' => $entity_type,
            'bundle' => $bundle,
            'label' => $values['label'],
            'widget' => array(
                'type' => $values['widget_type'],
                'weight' => $values['weight'],
            ),
        );
        // Create the field and instance.
        try {
            field_create_field($field);
            field_create_instance($instance);
            $destinations[] = $admin_path . '/fields/' . $field['field_name'] . '/field-settings';
            $destinations[] = $admin_path . '/fields/' . $field['field_name'];
            // Store new field information for any additional submit handlers.
            $form_state['fields_added']['_add_new_field'] = $field['field_name'];
        } catch (Exception $e) {
            drupal_set_message(t('There was a problem creating field %label: !message', array(
                '%label' => $instance['label'],
                '!message' => $e->getMessage(),
            )), 'error');
        }
    }
    // Add existing field.
    if (!empty($form_values['_add_existing_field']['field_name'])) {
        $values = $form_values['_add_existing_field'];
        $field = field_info_field($values['field_name']);
        if (!empty($field['locked'])) {
            drupal_set_message(t('The field %label cannot be added because it is locked.', array(
                '%label' => $values['label'],
            )), 'error');
        }
        else {
            $instance = array(
                'field_name' => $field['field_name'],
                'entity_type' => $entity_type,
                'bundle' => $bundle,
                'label' => $values['label'],
                'widget' => array(
                    'type' => $values['widget_type'],
                    'weight' => $values['weight'],
                ),
            );
            try {
                field_create_instance($instance);
                $destinations[] = $admin_path . '/fields/' . $instance['field_name'] . '/edit';
                // Store new field information for any additional submit handlers.
                $form_state['fields_added']['_add_existing_field'] = $instance['field_name'];
            } catch (Exception $e) {
                drupal_set_message(t('There was a problem creating field instance %label: @message.', array(
                    '%label' => $instance['label'],
                    '@message' => $e->getMessage(),
                )), 'error');
            }
        }
    }
    if ($destinations) {
        $destination = drupal_get_destination();
        $destinations[] = $destination['destination'];
        unset($_GET['destination']);
        $form_state['redirect'] = field_ui_get_destinations($destinations);
    }
    else {
        drupal_set_message(t('Your settings have been saved.'));
    }
}

/**
 * Form constructor for the field display settings for a given view mode.
 *
 * @see field_ui_display_overview_multistep_submit()
 * @see field_ui_display_overview_form_submit()
 * @ingroup forms
 */
function field_ui_display_overview_form($form, &$form_state, $entity_type, $bundle, $view_mode) {
    $bundle = field_extract_bundle($entity_type, $bundle);
    field_ui_inactive_message($entity_type, $bundle);
    $admin_path = _field_ui_bundle_admin_path($entity_type, $bundle);
    // Gather type information.
    $instances = field_info_instances($entity_type, $bundle);
    $field_types = field_info_field_types();
    $extra_fields = field_info_extra_fields($entity_type, $bundle, 'display');
    $form_state += array(
        'formatter_settings_edit' => NULL,
    );
    $form += array(
        '#entity_type' => $entity_type,
        '#bundle' => $bundle,
        '#view_mode' => $view_mode,
        '#fields' => array_keys($instances),
        '#extra' => array_keys($extra_fields),
    );
    if (empty($instances) && empty($extra_fields)) {
        drupal_set_message(t('There are no fields yet added. You can add new fields on the <a href="@link">Manage fields</a> page.', array(
            '@link' => url($admin_path . '/fields'),
        )), 'warning');
        return $form;
    }
    $table = array(
        '#type' => 'field_ui_table',
        '#tree' => TRUE,
        '#header' => array(
            t('Field'),
            t('Weight'),
            t('Parent'),
            t('Label'),
            array(
                'data' => t('Format'),
                'colspan' => 3,
            ),
        ),
        '#regions' => array(
            'visible' => array(
                'message' => t('No field is displayed.'),
            ),
            'hidden' => array(
                'title' => t('Hidden'),
                'message' => t('No field is hidden.'),
            ),
        ),
        '#parent_options' => array(),
        '#attributes' => array(
            'class' => array(
                'field-ui-overview',
            ),
            'id' => 'field-display-overview',
        ),
        // Add Ajax wrapper.
'#prefix' => '<div id="field-display-overview-wrapper">',
        '#suffix' => '</div>',
    );
    $field_label_options = array(
        'above' => t('Above'),
        'inline' => t('Inline'),
        'hidden' => '<' . t('Hidden') . '>',
    );
    $extra_visibility_options = array(
        'visible' => t('Visible'),
        'hidden' => t('Hidden'),
    );
    // Field rows.
    foreach ($instances as $name => $instance) {
        $field = field_info_field($instance['field_name']);
        $display = $instance['display'][$view_mode];
        $table[$name] = array(
            '#attributes' => array(
                'class' => array(
                    'draggable',
                    'tabledrag-leaf',
                ),
            ),
            '#row_type' => 'field',
            '#region_callback' => 'field_ui_display_overview_row_region',
            '#js_settings' => array(
                'rowHandler' => 'field',
                'defaultFormatter' => $field_types[$field['type']]['default_formatter'],
            ),
            'human_name' => array(
                '#markup' => check_plain($instance['label']),
            ),
            'weight' => array(
                '#type' => 'textfield',
                '#title' => t('Weight for @title', array(
                    '@title' => $instance['label'],
                )),
                '#title_display' => 'invisible',
                '#default_value' => $display['weight'],
                '#size' => 3,
                '#attributes' => array(
                    'class' => array(
                        'field-weight',
                    ),
                ),
            ),
            'parent_wrapper' => array(
                'parent' => array(
                    '#type' => 'select',
                    '#title' => t('Label display for @title', array(
                        '@title' => $instance['label'],
                    )),
                    '#title_display' => 'invisible',
                    '#options' => $table['#parent_options'],
                    '#empty_value' => '',
                    '#attributes' => array(
                        'class' => array(
                            'field-parent',
                        ),
                    ),
                    '#parents' => array(
                        'fields',
                        $name,
                        'parent',
                    ),
                ),
                'hidden_name' => array(
                    '#type' => 'hidden',
                    '#default_value' => $name,
                    '#attributes' => array(
                        'class' => array(
                            'field-name',
                        ),
                    ),
                ),
            ),
            'label' => array(
                '#type' => 'select',
                '#title' => t('Label display for @title', array(
                    '@title' => $instance['label'],
                )),
                '#title_display' => 'invisible',
                '#options' => $field_label_options,
                '#default_value' => $display['label'],
            ),
        );
        $formatter_options = field_ui_formatter_options($field['type']);
        $formatter_options['hidden'] = '<' . t('Hidden') . '>';
        $table[$name]['format'] = array(
            'type' => array(
                '#type' => 'select',
                '#title' => t('Formatter for @title', array(
                    '@title' => $instance['label'],
                )),
                '#title_display' => 'invisible',
                '#options' => $formatter_options,
                '#default_value' => $display['type'],
                '#parents' => array(
                    'fields',
                    $name,
                    'type',
                ),
                '#attributes' => array(
                    'class' => array(
                        'field-formatter-type',
                    ),
                ),
            ),
            'settings_edit_form' => array(),
        );
        // Formatter settings.
        // Check the currently selected formatter, and merge persisted values for
        // formatter settings.
        if (isset($form_state['values']['fields'][$name]['type'])) {
            $formatter_type = $form_state['values']['fields'][$name]['type'];
        }
        else {
            $formatter_type = $display['type'];
        }
        if (isset($form_state['formatter_settings'][$name])) {
            $settings = $form_state['formatter_settings'][$name];
        }
        else {
            $settings = $display['settings'];
        }
        $settings += field_info_formatter_settings($formatter_type);
        $instance['display'][$view_mode]['type'] = $formatter_type;
        $formatter = field_info_formatter_types($formatter_type);
        // For hidden fields, $formatter will be NULL, but we expect an array later.
        // To maintain BC, but avoid PHP 7.4 Notices, ensure $formatter is an array
        // with a 'module' element.
        $formatter['module'] = isset($formatter['module']) ? $formatter['module'] : '';
        $instance['display'][$view_mode]['module'] = $formatter['module'];
        $instance['display'][$view_mode]['settings'] = $settings;
        // Base button element for the various formatter settings actions.
        $base_button = array(
            '#submit' => array(
                'field_ui_display_overview_multistep_submit',
            ),
            '#ajax' => array(
                'callback' => 'field_ui_display_overview_multistep_js',
                'wrapper' => 'field-display-overview-wrapper',
                'effect' => 'fade',
            ),
            '#field_name' => $name,
        );
        if ($form_state['formatter_settings_edit'] == $name) {
            // We are currently editing this field's formatter settings. Display the
            // settings form and submit buttons.
            $table[$name]['format']['settings_edit_form'] = array();
            $settings_form = array();
            $function = $formatter['module'] . '_field_formatter_settings_form';
            if (function_exists($function)) {
                $settings_form = $function($field, $instance, $view_mode, $form, $form_state);
            }
            if ($settings_form) {
                $table[$name]['format']['#cell_attributes'] = array(
                    'colspan' => 3,
                );
                $table[$name]['format']['settings_edit_form'] = array(
                    '#type' => 'container',
                    '#attributes' => array(
                        'class' => array(
                            'field-formatter-settings-edit-form',
                        ),
                    ),
                    '#parents' => array(
                        'fields',
                        $name,
                        'settings_edit_form',
                    ),
                    'label' => array(
                        '#markup' => t('Format settings:') . ' <span class="formatter-name">' . $formatter['label'] . '</span>',
                    ),
                    'settings' => $settings_form,
                    'actions' => array(
                        '#type' => 'actions',
                        'save_settings' => $base_button + array(
                            '#type' => 'submit',
                            '#name' => $name . '_formatter_settings_update',
                            '#value' => t('Update'),
                            '#op' => 'update',
                        ),
                        'cancel_settings' => $base_button + array(
                            '#type' => 'submit',
                            '#name' => $name . '_formatter_settings_cancel',
                            '#value' => t('Cancel'),
                            '#op' => 'cancel',
                            // Do not check errors for the 'Cancel' button, but make sure we
                            // get the value of the 'formatter type' select.
'#limit_validation_errors' => array(
                                array(
                                    'fields',
                                    $name,
                                    'type',
                                ),
                            ),
                        ),
                    ),
                );
                $table[$name]['#attributes']['class'][] = 'field-formatter-settings-editing';
            }
        }
        else {
            // Display a summary of the current formatter settings.
            $summary = module_invoke($formatter['module'], 'field_formatter_settings_summary', $field, $instance, $view_mode);
            $table[$name]['settings_summary'] = array();
            $table[$name]['settings_edit'] = array();
            if ($summary) {
                $table[$name]['settings_summary'] = array(
                    '#markup' => '<div class="field-formatter-summary">' . $summary . '</div>',
                    '#cell_attributes' => array(
                        'class' => array(
                            'field-formatter-summary-cell',
                        ),
                    ),
                );
                $table[$name]['settings_edit'] = $base_button + array(
                    '#type' => 'image_button',
                    '#name' => $name . '_formatter_settings_edit',
                    '#src' => 'misc/configure.png',
                    '#attributes' => array(
                        'class' => array(
                            'field-formatter-settings-edit',
                        ),
                        'alt' => t('Edit'),
                    ),
                    '#op' => 'edit',
                    // Do not check errors for the 'Edit' button, but make sure we get
                    // the value of the 'formatter type' select.
'#limit_validation_errors' => array(
                        array(
                            'fields',
                            $name,
                            'type',
                        ),
                    ),
                    '#prefix' => '<div class="field-formatter-settings-edit-wrapper">',
                    '#suffix' => '</div>',
                );
            }
        }
    }
    // Non-field elements.
    foreach ($extra_fields as $name => $extra_field) {
        $display = $extra_field['display'][$view_mode];
        $table[$name] = array(
            '#attributes' => array(
                'class' => array(
                    'draggable',
                    'tabledrag-leaf',
                ),
            ),
            '#row_type' => 'extra_field',
            '#region_callback' => 'field_ui_display_overview_row_region',
            '#js_settings' => array(
                'rowHandler' => 'field',
            ),
            'human_name' => array(
                '#markup' => check_plain($extra_field['label']),
            ),
            'weight' => array(
                '#type' => 'textfield',
                '#title' => t('Weight for @title', array(
                    '@title' => $extra_field['label'],
                )),
                '#title_display' => 'invisible',
                '#default_value' => $display['weight'],
                '#size' => 3,
                '#attributes' => array(
                    'class' => array(
                        'field-weight',
                    ),
                ),
            ),
            'parent_wrapper' => array(
                'parent' => array(
                    '#type' => 'select',
                    '#title' => t('Parents for @title', array(
                        '@title' => $extra_field['label'],
                    )),
                    '#title_display' => 'invisible',
                    '#options' => $table['#parent_options'],
                    '#empty_value' => '',
                    '#attributes' => array(
                        'class' => array(
                            'field-parent',
                        ),
                    ),
                    '#parents' => array(
                        'fields',
                        $name,
                        'parent',
                    ),
                ),
                'hidden_name' => array(
                    '#type' => 'hidden',
                    '#default_value' => $name,
                    '#attributes' => array(
                        'class' => array(
                            'field-name',
                        ),
                    ),
                ),
            ),
            'empty_cell' => array(
                '#markup' => '&nbsp;',
            ),
            'format' => array(
                'type' => array(
                    '#type' => 'select',
                    '#title' => t('Visibility for @title', array(
                        '@title' => $extra_field['label'],
                    )),
                    '#title_display' => 'invisible',
                    '#options' => $extra_visibility_options,
                    '#default_value' => $display['visible'] ? 'visible' : 'hidden',
                    '#parents' => array(
                        'fields',
                        $name,
                        'type',
                    ),
                    '#attributes' => array(
                        'class' => array(
                            'field-formatter-type',
                        ),
                    ),
                ),
            ),
            'settings_summary' => array(),
            'settings_edit' => array(),
        );
    }
    $form['fields'] = $table;
    // Custom display settings.
    if ($view_mode == 'default') {
        $form['modes'] = array(
            '#type' => 'fieldset',
            '#title' => t('Custom display settings'),
            '#collapsible' => TRUE,
            '#collapsed' => TRUE,
        );
        // Collect options and default values for the 'Custom display settings'
        // checkboxes.
        $options = array();
        $default = array();
        $entity_info = entity_get_info($entity_type);
        $view_modes = $entity_info['view modes'];
        $view_mode_settings = field_view_mode_settings($entity_type, $bundle);
        foreach ($view_modes as $view_mode_name => $view_mode_info) {
            $options[$view_mode_name] = $view_mode_info['label'];
            if (!empty($view_mode_settings[$view_mode_name]['custom_settings'])) {
                $default[] = $view_mode_name;
            }
        }
        $form['modes']['view_modes_custom'] = array(
            '#type' => 'checkboxes',
            '#title' => t('Use custom display settings for the following view modes'),
            '#options' => $options,
            '#default_value' => $default,
        );
    }
    // In overviews involving nested rows from contributed modules (i.e
    // field_group), the 'format type' selects can trigger a series of changes in
    // child rows. The #ajax behavior is therefore not attached directly to the
    // selects, but triggered by the client-side script through a hidden #ajax
    // 'Refresh' button. A hidden 'refresh_rows' input tracks the name of
    // affected rows.
    $form['refresh_rows'] = array(
        '#type' => 'hidden',
    );
    $form['refresh'] = array(
        '#type' => 'submit',
        '#value' => t('Refresh'),
        '#op' => 'refresh_table',
        '#submit' => array(
            'field_ui_display_overview_multistep_submit',
        ),
        '#ajax' => array(
            'callback' => 'field_ui_display_overview_multistep_js',
            'wrapper' => 'field-display-overview-wrapper',
            'effect' => 'fade',
            // The button stays hidden, so we hide the Ajax spinner too. Ad-hoc
            // spinners will be added manually by the client-side script.
'progress' => 'none',
        ),
    );
    $form['actions'] = array(
        '#type' => 'actions',
    );
    $form['actions']['submit'] = array(
        '#type' => 'submit',
        '#value' => t('Save'),
    );
    $form['#attached']['js'][] = drupal_get_path('module', 'field_ui') . '/field_ui.js';
    $form['#attached']['css'][] = drupal_get_path('module', 'field_ui') . '/field_ui.css';
    // Add tabledrag behavior.
    $form['#attached']['drupal_add_tabledrag'][] = array(
        'field-display-overview',
        'order',
        'sibling',
        'field-weight',
    );
    $form['#attached']['drupal_add_tabledrag'][] = array(
        'field-display-overview',
        'match',
        'parent',
        'field-parent',
        'field-parent',
        'field-name',
    );
    return $form;
}

/**
 * Form submission handler for buttons in field_ui_display_overview_form().
 */
function field_ui_display_overview_multistep_submit($form, &$form_state) {
    $trigger = $form_state['triggering_element'];
    $op = $trigger['#op'];
    switch ($op) {
        case 'edit':
            // Store the field whose settings are currently being edited.
            $field_name = $trigger['#field_name'];
            $form_state['formatter_settings_edit'] = $field_name;
            break;
        case 'update':
            // Store the saved settings, and set the field back to 'non edit' mode.
            $field_name = $trigger['#field_name'];
            $values = $form_state['values']['fields'][$field_name]['settings_edit_form']['settings'];
            $form_state['formatter_settings'][$field_name] = $values;
            unset($form_state['formatter_settings_edit']);
            break;
        case 'cancel':
            // Set the field back to 'non edit' mode.
            unset($form_state['formatter_settings_edit']);
            break;
        case 'refresh_table':
            // If the currently edited field is one of the rows to be refreshed, set
            // it back to 'non edit' mode.
            $updated_rows = explode(' ', $form_state['values']['refresh_rows']);
            if (isset($form_state['formatter_settings_edit']) && in_array($form_state['formatter_settings_edit'], $updated_rows)) {
                unset($form_state['formatter_settings_edit']);
            }
            break;
    }
    $form_state['rebuild'] = TRUE;
}

/**
 * Ajax handler for multistep buttons on the 'Manage display' screen.
 */
function field_ui_display_overview_multistep_js($form, &$form_state) {
    $trigger = $form_state['triggering_element'];
    $op = $trigger['#op'];
    // Pick the elements that need to receive the ajax-new-content effect.
    switch ($op) {
        case 'edit':
            $updated_rows = array(
                $trigger['#field_name'],
            );
            $updated_columns = array(
                'format',
            );
            break;
        case 'update':
        case 'cancel':
            $updated_rows = array(
                $trigger['#field_name'],
            );
            $updated_columns = array(
                'format',
                'settings_summary',
                'settings_edit',
            );
            break;
        case 'refresh_table':
            $updated_rows = array_values(explode(' ', $form_state['values']['refresh_rows']));
            $updated_columns = array(
                'settings_summary',
                'settings_edit',
            );
            break;
    }
    foreach ($updated_rows as $name) {
        foreach ($updated_columns as $key) {
            $element =& $form['fields'][$name][$key];
            $element['#prefix'] = '<div class="ajax-new-content">' . (isset($element['#prefix']) ? $element['#prefix'] : '');
            $element['#suffix'] = (isset($element['#suffix']) ? $element['#suffix'] : '') . '</div>';
        }
    }
    // Return the whole table.
    return $form['fields'];
}

/**
 * Form submission handler for field_ui_display_overview_form().
 */
function field_ui_display_overview_form_submit($form, &$form_state) {
    $form_values = $form_state['values'];
    $entity_type = $form['#entity_type'];
    $bundle = $form['#bundle'];
    $view_mode = $form['#view_mode'];
    // Save data for 'regular' fields.
    foreach ($form['#fields'] as $field_name) {
        // Retrieve the stored instance settings to merge with the incoming values.
        $instance = field_read_instance($entity_type, $field_name, $bundle);
        $values = $form_values['fields'][$field_name];
        // Get formatter settings. They lie either directly in submitted form
        // values (if the whole form was submitted while some formatter
        // settings were being edited), or have been persisted in
        // $form_state.
        $settings = array();
        if (isset($values['settings_edit_form']['settings'])) {
            $settings = $values['settings_edit_form']['settings'];
        }
        elseif (isset($form_state['formatter_settings'][$field_name])) {
            $settings = $form_state['formatter_settings'][$field_name];
        }
        elseif (isset($instance['display'][$view_mode]['settings'])) {
            $settings = $instance['display'][$view_mode]['settings'];
        }
        // Only save settings actually used by the selected formatter.
        $default_settings = field_info_formatter_settings($values['type']);
        $settings = array_intersect_key($settings, $default_settings);
        $instance['display'][$view_mode] = array(
            'label' => $values['label'],
            'type' => $values['type'],
            'weight' => $values['weight'],
            'settings' => $settings,
        );
        field_update_instance($instance);
    }
    // Get current bundle settings.
    $bundle_settings = field_bundle_settings($entity_type, $bundle);
    // Save data for 'extra' fields.
    foreach ($form['#extra'] as $name) {
        $bundle_settings['extra_fields']['display'][$name][$view_mode] = array(
            'weight' => $form_values['fields'][$name]['weight'],
            'visible' => $form_values['fields'][$name]['type'] == 'visible',
        );
    }
    // Save view modes data.
    if ($view_mode == 'default') {
        $entity_info = entity_get_info($entity_type);
        foreach ($form_values['view_modes_custom'] as $view_mode_name => $value) {
            // Display a message for each view mode newly configured to use custom
            // settings.
            $view_mode_settings = field_view_mode_settings($entity_type, $bundle);
            if (!empty($value) && empty($view_mode_settings[$view_mode_name]['custom_settings'])) {
                $view_mode_label = $entity_info['view modes'][$view_mode_name]['label'];
                $path = _field_ui_bundle_admin_path($entity_type, $bundle) . "/display/{$view_mode_name}";
                drupal_set_message(t('The %view_mode mode now uses custom display settings. You might want to <a href="@url">configure them</a>.', array(
                    '%view_mode' => $view_mode_label,
                    '@url' => url($path),
                )));
                // Initialize the newly customized view mode with the display settings
                // from the default view mode.
                _field_ui_add_default_view_mode_settings($entity_type, $bundle, $view_mode_name, $bundle_settings);
            }
            $bundle_settings['view_modes'][$view_mode_name]['custom_settings'] = !empty($value);
        }
    }
    // Save updated bundle settings.
    field_bundle_settings($entity_type, $bundle, $bundle_settings);
    drupal_set_message(t('Your settings have been saved.'));
}

/**
 * Populates display settings for a new view mode from the default view mode.
 *
 * When an administrator decides to use custom display settings for a view mode,
 * that view mode needs to be initialized with the display settings for the
 * 'default' view mode, which it was previously using. This helper function
 * adds the new custom display settings to this bundle's instances, and saves
 * them. It also modifies the passed-in $settings array, which the caller can
 * then save using field_bundle_settings().
 *
 * @param $entity_type
 *   The bundle's entity type.
 * @param $bundle
 *   The bundle whose view mode is being customized.
 * @param $view_mode
 *   The view mode that the administrator has set to use custom settings.
 * @param $settings
 *   An associative array of bundle settings, as expected by
 *   field_bundle_settings().
 *
 * @see field_ui_display_overview_form_submit().
 * @see field_bundle_settings()
 */
function _field_ui_add_default_view_mode_settings($entity_type, $bundle, $view_mode, &$settings) {
    // Update display settings for field instances.
    $instances = field_read_instances(array(
        'entity_type' => $entity_type,
        'bundle' => $bundle,
    ));
    foreach ($instances as $instance) {
        // If this field instance has display settings defined for this view mode,
        // respect those settings.
        if (!isset($instance['display'][$view_mode])) {
            // The instance doesn't specify anything for this view mode, so use the
            // default display settings.
            $instance['display'][$view_mode] = $instance['display']['default'];
            field_update_instance($instance);
        }
    }
    // Update display settings for 'extra fields'.
    foreach (array_keys($settings['extra_fields']['display']) as $name) {
        if (!isset($settings['extra_fields']['display'][$name][$view_mode])) {
            $settings['extra_fields']['display'][$name][$view_mode] = $settings['extra_fields']['display'][$name]['default'];
        }
    }
}

/**
 * Returns an array of field_type options.
 */
function field_ui_field_type_options() {
    $options =& drupal_static(__FUNCTION__);
    if (!isset($options)) {
        $options = array();
        $field_types = field_info_field_types();
        $field_type_options = array();
        foreach ($field_types as $name => $field_type) {
            // Skip field types which have no widget types, or should not be add via
            // uesr interface.
            if (field_ui_widget_type_options($name) && empty($field_type['no_ui'])) {
                $options[$name] = $field_type['label'];
            }
        }
        asort($options);
    }
    return $options;
}

/**
 * Returns an array of widget type options for a field type.
 *
 * If no field type is provided, returns a nested array of all widget types,
 * keyed by field type human name.
 */
function field_ui_widget_type_options($field_type = NULL, $by_label = FALSE) {
    $options =& drupal_static(__FUNCTION__);
    if (!isset($options)) {
        $options = array();
        $field_types = field_info_field_types();
        foreach (field_info_widget_types() as $name => $widget_type) {
            foreach ($widget_type['field types'] as $widget_field_type) {
                // Check that the field type exists.
                if (isset($field_types[$widget_field_type])) {
                    $options[$widget_field_type][$name] = $widget_type['label'];
                }
            }
        }
    }
    if (isset($field_type)) {
        return !empty($options[$field_type]) ? $options[$field_type] : array();
    }
    if ($by_label) {
        $field_types = field_info_field_types();
        $options_by_label = array();
        foreach ($options as $field_type => $widgets) {
            $options_by_label[$field_types[$field_type]['label']] = $widgets;
        }
        return $options_by_label;
    }
    return $options;
}

/**
 * Returns an array of formatter options for a field type.
 *
 * If no field type is provided, returns a nested array of all formatters, keyed
 * by field type.
 */
function field_ui_formatter_options($field_type = NULL) {
    $options =& drupal_static(__FUNCTION__);
    if (!isset($options)) {
        $field_types = field_info_field_types();
        $options = array();
        foreach (field_info_formatter_types() as $name => $formatter) {
            foreach ($formatter['field types'] as $formatter_field_type) {
                // Check that the field type exists.
                if (isset($field_types[$formatter_field_type])) {
                    $options[$formatter_field_type][$name] = $formatter['label'];
                }
            }
        }
    }
    if ($field_type) {
        return !empty($options[$field_type]) ? $options[$field_type] : array();
    }
    return $options;
}

/**
 * Returns an array of existing fields to be added to a bundle.
 */
function field_ui_existing_field_options($entity_type, $bundle) {
    $info = array();
    $field_types = field_info_field_types();
    foreach (field_info_instances() as $existing_entity_type => $bundles) {
        foreach ($bundles as $existing_bundle => $instances) {
            // No need to look in the current bundle.
            if (!($existing_bundle == $bundle && $existing_entity_type == $entity_type)) {
                foreach ($instances as $instance) {
                    $field = field_info_field($instance['field_name']);
                    // Don't show
                    // - locked fields,
                    // - fields already in the current bundle,
                    // - fields that cannot be added to the entity type,
                    // - fields that should not be added via user interface.
                    if (empty($field['locked']) && !field_info_instance($entity_type, $field['field_name'], $bundle) && (empty($field['entity_types']) || in_array($entity_type, $field['entity_types'])) && empty($field_types[$field['type']]['no_ui'])) {
                        $info[$instance['field_name']] = array(
                            'type' => $field['type'],
                            'type_label' => $field_types[$field['type']]['label'],
                            'field' => $field['field_name'],
                            'label' => $instance['label'],
                            'widget_type' => $instance['widget']['type'],
                        );
                    }
                }
            }
        }
    }
    return $info;
}

/**
 * Form constructor for the field settings edit page.
 *
 * @see field_ui_field_settings_form_submit()
 * @ingroup forms
 */
function field_ui_field_settings_form($form, &$form_state, $instance) {
    $bundle = $instance['bundle'];
    $entity_type = $instance['entity_type'];
    $field = field_info_field($instance['field_name']);
    drupal_set_title($instance['label']);
    $description = '<p>' . t('These settings apply to the %field field everywhere it is used. These settings impact the way that data is stored in the database and cannot be changed once data has been created.', array(
        '%field' => $instance['label'],
    )) . '</p>';
    // Create a form structure for the field values.
    $form['field'] = array(
        '#type' => 'fieldset',
        '#title' => t('Field settings'),
        '#description' => $description,
        '#tree' => TRUE,
    );
    // See if data already exists for this field.
    // If so, prevent changes to the field settings.
    $has_data = field_has_data($field);
    if ($has_data) {
        $form['field']['#description'] = '<div class="messages error">' . t('There is data for this field in the database. The field settings can no longer be changed.') . '</div>' . $form['field']['#description'];
    }
    // Build the non-configurable field values.
    $form['field']['field_name'] = array(
        '#type' => 'value',
        '#value' => $field['field_name'],
    );
    $form['field']['type'] = array(
        '#type' => 'value',
        '#value' => $field['type'],
    );
    $form['field']['module'] = array(
        '#type' => 'value',
        '#value' => $field['module'],
    );
    $form['field']['active'] = array(
        '#type' => 'value',
        '#value' => $field['active'],
    );
    // Add settings provided by the field module. The field module is
    // responsible for not returning settings that cannot be changed if
    // the field already has data.
    $form['field']['settings'] = array();
    $additions = module_invoke($field['module'], 'field_settings_form', $field, $instance, $has_data);
    if (is_array($additions)) {
        $form['field']['settings'] = $additions;
    }
    if (empty($form['field']['settings'])) {
        $form['field']['settings'] = array(
            '#markup' => t('%field has no field settings.', array(
                '%field' => $instance['label'],
            )),
        );
    }
    $form['#entity_type'] = $entity_type;
    $form['#bundle'] = $bundle;
    $form['actions'] = array(
        '#type' => 'actions',
    );
    $form['actions']['submit'] = array(
        '#type' => 'submit',
        '#value' => t('Save field settings'),
    );
    return $form;
}

/**
 * Form submission handler for field_ui_field_settings_form().
 */
function field_ui_field_settings_form_submit($form, &$form_state) {
    $form_values = $form_state['values'];
    $field_values = $form_values['field'];
    // Merge incoming form values into the existing field.
    $field = field_info_field($field_values['field_name']);
    $entity_type = $form['#entity_type'];
    $bundle = $form['#bundle'];
    $instance = field_info_instance($entity_type, $field['field_name'], $bundle);
    // Update the field.
    $field = array_merge($field, $field_values);
    try {
        field_update_field($field);
        drupal_set_message(t('Updated field %label field settings.', array(
            '%label' => $instance['label'],
        )));
        $form_state['redirect'] = field_ui_next_destination($entity_type, $bundle);
    } catch (Exception $e) {
        drupal_set_message(t('Attempt to update field %label failed: %message.', array(
            '%label' => $instance['label'],
            '%message' => $e->getMessage(),
        )), 'error');
    }
}

/**
 * Form constructor for the widget selection form.
 *
 * Path: BUNDLE_ADMIN_PATH/fields/%field/widget-type, where BUNDLE_ADMIN_PATH is
 * the path stored in the ['admin']['info'] property in the return value of
 * hook_entity_info().
 *
 * @see field_ui_menu()
 * @see field_ui_widget_type_form_submit()
 * @ingroup forms
 */
function field_ui_widget_type_form($form, &$form_state, $instance) {
    drupal_set_title($instance['label']);
    $bundle = $instance['bundle'];
    $entity_type = $instance['entity_type'];
    $field_name = $instance['field_name'];
    $field = field_info_field($field_name);
    $field_type = field_info_field_types($field['type']);
    $widget_type = field_info_widget_types($instance['widget']['type']);
    $bundles = field_info_bundles();
    $bundle_label = $bundles[$entity_type][$bundle]['label'];
    $form = array(
        '#bundle' => $bundle,
        '#entity_type' => $entity_type,
        '#field_name' => $field_name,
    );
    $form['basic'] = array(
        '#type' => 'fieldset',
        '#title' => t('Change widget'),
    );
    $form['basic']['widget_type'] = array(
        '#type' => 'select',
        '#title' => t('Widget type'),
        '#required' => TRUE,
        '#options' => field_ui_widget_type_options($field['type']),
        '#default_value' => $instance['widget']['type'],
        '#description' => t('The type of form element you would like to present to the user when creating this field in the %type type.', array(
            '%type' => $bundle_label,
        )),
    );
    $form['actions'] = array(
        '#type' => 'actions',
    );
    $form['actions']['submit'] = array(
        '#type' => 'submit',
        '#value' => t('Continue'),
    );
    $form['#validate'] = array();
    $form['#submit'] = array(
        'field_ui_widget_type_form_submit',
    );
    return $form;
}

/**
 * Form submission handler for field_ui_widget_type_form().
 */
function field_ui_widget_type_form_submit($form, &$form_state) {
    $form_values = $form_state['values'];
    $bundle = $form['#bundle'];
    $entity_type = $form['#entity_type'];
    $field_name = $form['#field_name'];
    // Retrieve the stored instance settings to merge with the incoming values.
    $instance = field_read_instance($entity_type, $field_name, $bundle);
    // Set the right module information.
    $widget_type = field_info_widget_types($form_values['widget_type']);
    $widget_module = $widget_type['module'];
    $instance['widget']['type'] = $form_values['widget_type'];
    $instance['widget']['module'] = $widget_module;
    try {
        field_update_instance($instance);
        drupal_set_message(t('Changed the widget for field %label.', array(
            '%label' => $instance['label'],
        )));
    } catch (Exception $e) {
        drupal_set_message(t('There was a problem changing the widget for field %label.', array(
            '%label' => $instance['label'],
        )), 'error');
    }
    $form_state['redirect'] = field_ui_next_destination($entity_type, $bundle);
}

/**
 * Form constructor for removing a field instance from a bundle.
 *
 * @see field_ui_field_delete_form_submit()
 * @ingroup forms
 */
function field_ui_field_delete_form($form, &$form_state, $instance) {
    $bundle = $instance['bundle'];
    $entity_type = $instance['entity_type'];
    $field = field_info_field($instance['field_name']);
    $admin_path = _field_ui_bundle_admin_path($entity_type, $bundle);
    $form['entity_type'] = array(
        '#type' => 'value',
        '#value' => $entity_type,
    );
    $form['bundle'] = array(
        '#type' => 'value',
        '#value' => $bundle,
    );
    $form['field_name'] = array(
        '#type' => 'value',
        '#value' => $field['field_name'],
    );
    $output = confirm_form($form, t('Are you sure you want to delete the field %field?', array(
        '%field' => $instance['label'],
    )), $admin_path . '/fields', t('If you have any content left in this field, it will be lost. This action cannot be undone.'), t('Delete'), t('Cancel'), 'confirm');
    if ($field['locked']) {
        unset($output['actions']['submit']);
        $output['description']['#markup'] = t('This field is <strong>locked</strong> and cannot be deleted.');
    }
    return $output;
}

/**
 * Form submission handler for field_ui_field_delete_form().
 *
 * Removes a field instance from a bundle. If the field has no more instances,
 * it will be marked as deleted too.
 */
function field_ui_field_delete_form_submit($form, &$form_state) {
    $form_values = $form_state['values'];
    $field_name = $form_values['field_name'];
    $bundle = $form_values['bundle'];
    $entity_type = $form_values['entity_type'];
    $field = field_info_field($field_name);
    $instance = field_info_instance($entity_type, $field_name, $bundle);
    $bundles = field_info_bundles();
    $bundle_label = $bundles[$entity_type][$bundle]['label'];
    if (!empty($bundle) && $field && !$field['locked'] && $form_values['confirm']) {
        field_delete_instance($instance);
        drupal_set_message(t('The field %field has been deleted from the %type content type.', array(
            '%field' => $instance['label'],
            '%type' => $bundle_label,
        )));
    }
    else {
        drupal_set_message(t('There was a problem removing the %field from the %type content type.', array(
            '%field' => $instance['label'],
            '%type' => $bundle_label,
        )), 'error');
    }
    $admin_path = _field_ui_bundle_admin_path($entity_type, $bundle);
    $form_state['redirect'] = field_ui_get_destinations(array(
        $admin_path . '/fields',
    ));
    // Fields are purged on cron. However field module prevents disabling modules
    // when field types they provided are used in a field until it is fully
    // purged. In the case that a field has minimal or no content, a single call
    // to field_purge_batch() will remove it from the system. Call this with a
    // low batch limit to avoid administrators having to wait for cron runs when
    // removing instances that meet this criteria.
    field_purge_batch(10);
}

/**
 * Form constructor for the field instance settings form.
 *
 * @see field_ui_field_edit_form_validate()
 * @see field_ui_field_edit_form_submit()
 * @ingroup forms
 */
function field_ui_field_edit_form($form, &$form_state, $instance) {
    $bundle = $instance['bundle'];
    $entity_type = $instance['entity_type'];
    $field = field_info_field($instance['field_name']);
    drupal_set_title($instance['label']);
    $form['#field'] = $field;
    $form['#instance'] = $instance;
    if (!empty($field['locked'])) {
        $form['locked'] = array(
            '#markup' => t('The field %field is locked and cannot be edited.', array(
                '%field' => $instance['label'],
            )),
        );
        return $form;
    }
    $field_type = field_info_field_types($field['type']);
    $widget_type = field_info_widget_types($instance['widget']['type']);
    $bundles = field_info_bundles();
    // Create a form structure for the instance values.
    $form['instance'] = array(
        '#tree' => TRUE,
        '#type' => 'fieldset',
        '#title' => t('%type settings', array(
            '%type' => $bundles[$entity_type][$bundle]['label'],
        )),
        '#description' => t('These settings apply only to the %field field when used in the %type type.', array(
            '%field' => $instance['label'],
            '%type' => $bundles[$entity_type][$bundle]['label'],
        )),
        // Ensure field_ui_field_edit_instance_pre_render() gets called in addition
        // to, not instead of, the #pre_render function(s) needed by all fieldsets.
'#pre_render' => array_merge(array(
            'field_ui_field_edit_instance_pre_render',
        ), element_info_property('fieldset', '#pre_render', array())),
    );
    // Build the non-configurable instance values.
    $form['instance']['field_name'] = array(
        '#type' => 'value',
        '#value' => $instance['field_name'],
    );
    $form['instance']['entity_type'] = array(
        '#type' => 'value',
        '#value' => $entity_type,
    );
    $form['instance']['bundle'] = array(
        '#type' => 'value',
        '#value' => $bundle,
    );
    $form['instance']['widget']['weight'] = array(
        '#type' => 'value',
        '#value' => !empty($instance['widget']['weight']) ? $instance['widget']['weight'] : 0,
    );
    // Build the configurable instance values.
    $form['instance']['label'] = array(
        '#type' => 'textfield',
        '#title' => t('Label'),
        '#default_value' => !empty($instance['label']) ? $instance['label'] : $field['field_name'],
        '#required' => TRUE,
        '#weight' => -20,
    );
    $form['instance']['required'] = array(
        '#type' => 'checkbox',
        '#title' => t('Required field'),
        '#default_value' => !empty($instance['required']),
        '#weight' => -10,
    );
    $form['instance']['description'] = array(
        '#type' => 'textarea',
        '#title' => t('Help text'),
        '#default_value' => !empty($instance['description']) ? $instance['description'] : '',
        '#rows' => 5,
        '#description' => t('Instructions to present to the user below this field on the editing form.<br />Allowed HTML tags: @tags', array(
            '@tags' => _field_filter_xss_display_allowed_tags(),
        )),
        '#weight' => -5,
    );
    // Build the widget component of the instance.
    $form['instance']['widget']['type'] = array(
        '#type' => 'value',
        '#value' => $instance['widget']['type'],
    );
    $form['instance']['widget']['module'] = array(
        '#type' => 'value',
        '#value' => $widget_type['module'],
    );
    $form['instance']['widget']['active'] = array(
        '#type' => 'value',
        '#value' => !empty($field['instance']['widget']['active']) ? 1 : 0,
    );
    // Add additional field instance settings from the field module.
    $additions = module_invoke($field['module'], 'field_instance_settings_form', $field, $instance);
    if (is_array($additions)) {
        $form['instance']['settings'] = $additions;
    }
    // Add additional widget settings from the widget module.
    $additions = module_invoke($widget_type['module'], 'field_widget_settings_form', $field, $instance);
    if (is_array($additions)) {
        $form['instance']['widget']['settings'] = $additions;
        $form['instance']['widget']['active']['#value'] = 1;
    }
    // Add handling for default value if not provided by any other module.
    if (field_behaviors_widget('default value', $instance) == FIELD_BEHAVIOR_DEFAULT && empty($instance['default_value_function'])) {
        $form['instance']['default_value_widget'] = field_ui_default_value_widget($field, $instance, $form, $form_state);
    }
    $has_data = field_has_data($field);
    if ($has_data) {
        $description = '<p>' . t('These settings apply to the %field field everywhere it is used. Because the field already has data, some settings can no longer be changed.', array(
            '%field' => $instance['label'],
        )) . '</p>';
    }
    else {
        $description = '<p>' . t('These settings apply to the %field field everywhere it is used.', array(
            '%field' => $instance['label'],
        )) . '</p>';
    }
    // Create a form structure for the field values.
    $form['field'] = array(
        '#type' => 'fieldset',
        '#title' => t('%field field settings', array(
            '%field' => $instance['label'],
        )),
        '#description' => $description,
        '#tree' => TRUE,
    );
    // Build the configurable field values.
    $description = t('Maximum number of values users can enter for this field.');
    if (field_behaviors_widget('multiple values', $instance) == FIELD_BEHAVIOR_DEFAULT) {
        $description .= '<br/>' . t("'Unlimited' will provide an 'Add more' button so the users can add as many values as they like.");
    }
    $form['field']['cardinality'] = array(
        '#type' => 'select',
        '#title' => t('Number of values'),
        '#options' => array(
            FIELD_CARDINALITY_UNLIMITED => t('Unlimited'),
        ) + drupal_map_assoc(range(1, 10)),
        '#default_value' => $field['cardinality'],
        '#description' => $description,
    );
    // Add additional field type settings. The field type module is
    // responsible for not returning settings that cannot be changed if
    // the field already has data.
    $additions = module_invoke($field['module'], 'field_settings_form', $field, $instance, $has_data);
    if (is_array($additions)) {
        $form['field']['settings'] = $additions;
    }
    $form['actions'] = array(
        '#type' => 'actions',
    );
    $form['actions']['submit'] = array(
        '#type' => 'submit',
        '#value' => t('Save settings'),
    );
    return $form;
}

/**
 * Pre-render function for field instance settings.
 *
 * Combines the instance, widget, and other settings into a single fieldset so
 * that elements within each group can be shown at different weights as if they
 * all had the same parent.
 */
function field_ui_field_edit_instance_pre_render($element) {
    // Merge the widget settings into the main form.
    if (isset($element['widget']['settings'])) {
        foreach (element_children($element['widget']['settings']) as $key) {
            $element['widget_' . $key] = $element['widget']['settings'][$key];
        }
        unset($element['widget']['settings']);
    }
    // Merge the instance settings into the main form.
    if (isset($element['settings'])) {
        foreach (element_children($element['settings']) as $key) {
            $element['instance_' . $key] = $element['settings'][$key];
        }
        unset($element['settings']);
    }
    return $element;
}

/**
 * Builds the default value fieldset for a given field instance.
 */
function field_ui_default_value_widget($field, $instance, &$form, &$form_state) {
    $field_name = $field['field_name'];
    $element = array(
        '#type' => 'fieldset',
        '#title' => t('Default value'),
        '#collapsible' => FALSE,
        '#tree' => TRUE,
        '#description' => t('The default value for this field, used when creating new content.'),
        // Stick to an empty 'parents' on this form in order not to breaks widgets
        // that do not use field_widget_[field|instance]() and still access
        // $form_state['field'] directly.
'#parents' => array(),
    );
    // Insert the widget.
    $items = $instance['default_value'];
    $instance['required'] = FALSE;
    $instance['description'] = '';
    // @todo Allow multiple values (requires more work on 'add more' JS handler).
    $element += field_default_form($instance['entity_type'], NULL, $field, $instance, LANGUAGE_NONE, $items, $element, $form_state, 0);
    return $element;
}

/**
 * Form validation handler for field_ui_field_edit_form().
 *
 * @see field_ui_field_edit_form_submit().
 */
function field_ui_field_edit_form_validate($form, &$form_state) {
    // Take the incoming values as the $instance definition, so that the 'default
    // value' gets validated using the instance settings being submitted.
    $instance = $form_state['values']['instance'];
    $field_name = $instance['field_name'];
    if (isset($form['instance']['default_value_widget'])) {
        $element = $form['instance']['default_value_widget'];
        $field_state = field_form_get_state($element['#parents'], $field_name, LANGUAGE_NONE, $form_state);
        $field = $field_state['field'];
        // Extract the 'default value'.
        $items = array();
        field_default_extract_form_values(NULL, NULL, $field, $instance, LANGUAGE_NONE, $items, $element, $form_state);
        // Validate the value and report errors.
        $errors = array();
        $function = $field['module'] . '_field_validate';
        if (function_exists($function)) {
            $function(NULL, NULL, $field, $instance, LANGUAGE_NONE, $items, $errors);
        }
        if (isset($errors[$field_name][LANGUAGE_NONE])) {
            // Store reported errors in $form_state.
            $field_state['errors'] = $errors[$field_name][LANGUAGE_NONE];
            field_form_set_state($element['#parents'], $field_name, LANGUAGE_NONE, $form_state, $field_state);
            // Assign reported errors to the correct form element.
            field_default_form_errors(NULL, NULL, $field, $instance, LANGUAGE_NONE, $items, $element, $form_state);
        }
    }
}

/**
 * Form submission handler for field_ui_field_edit_form().
 *
 * @see field_ui_field_edit_form_validate().
 */
function field_ui_field_edit_form_submit($form, &$form_state) {
    $instance = $form_state['values']['instance'];
    $field = $form_state['values']['field'];
    // Update any field settings that have changed.
    $field_source = field_info_field($instance['field_name']);
    $field = array_merge($field_source, $field);
    try {
        field_update_field($field);
    } catch (Exception $e) {
        drupal_set_message(t('Attempt to update field %label failed: %message.', array(
            '%label' => $instance['label'],
            '%message' => $e->getMessage(),
        )), 'error');
        return;
    }
    // Handle the default value.
    if (isset($form['instance']['default_value_widget'])) {
        $element = $form['instance']['default_value_widget'];
        // Extract field values.
        $items = array();
        field_default_extract_form_values(NULL, NULL, $field, $instance, LANGUAGE_NONE, $items, $element, $form_state);
        field_default_submit(NULL, NULL, $field, $instance, LANGUAGE_NONE, $items, $element, $form_state);
        $instance['default_value'] = $items ? $items : NULL;
    }
    // Retrieve the stored instance settings to merge with the incoming values.
    $instance_source = field_read_instance($instance['entity_type'], $instance['field_name'], $instance['bundle']);
    $instance = array_merge($instance_source, $instance);
    field_update_instance($instance);
    drupal_set_message(t('Saved %label configuration.', array(
        '%label' => $instance['label'],
    )));
    $form_state['redirect'] = field_ui_next_destination($instance['entity_type'], $instance['bundle']);
}

/**
 * Extracts next redirect path from an array of multiple destinations.
 *
 * @see field_ui_next_destination()
 */
function field_ui_get_destinations($destinations) {
    $path = array_shift($destinations);
    $options = drupal_parse_url($path);
    if ($destinations) {
        $options['query']['destinations'] = $destinations;
    }
    return array(
        $options['path'],
        $options,
    );
}

/**
 * Returns the next redirect path in a multipage sequence.
 */
function field_ui_next_destination($entity_type, $bundle) {
    $destinations = !empty($_REQUEST['destinations']) ? $_REQUEST['destinations'] : array();
    if (!empty($destinations)) {
        unset($_REQUEST['destinations']);
    }
    // Remove any external URLs.
    $destinations = array_diff($destinations, array_filter($destinations, 'url_is_external'));
    if ($destinations) {
        return field_ui_get_destinations($destinations);
    }
    $admin_path = _field_ui_bundle_admin_path($entity_type, $bundle);
    return $admin_path . '/fields';
}

Functions

Title Deprecated Summary
field_ui_default_value_widget Builds the default value fieldset for a given field instance.
field_ui_display_overview_form Form constructor for the field display settings for a given view mode.
field_ui_display_overview_form_submit Form submission handler for field_ui_display_overview_form().
field_ui_display_overview_multistep_js Ajax handler for multistep buttons on the 'Manage display' screen.
field_ui_display_overview_multistep_submit Form submission handler for buttons in field_ui_display_overview_form().
field_ui_display_overview_row_region Returns the region to which a row in the 'Manage display' screen belongs.
field_ui_existing_field_options Returns an array of existing fields to be added to a bundle.
field_ui_fields_list Menu callback; lists all defined fields for quick reference.
field_ui_field_delete_form Form constructor for removing a field instance from a bundle.
field_ui_field_delete_form_submit Form submission handler for field_ui_field_delete_form().
field_ui_field_edit_form Form constructor for the field instance settings form.
field_ui_field_edit_form_submit Form submission handler for field_ui_field_edit_form().
field_ui_field_edit_form_validate Form validation handler for field_ui_field_edit_form().
field_ui_field_edit_instance_pre_render Pre-render function for field instance settings.
field_ui_field_overview_form Form constructor for the 'Manage fields' form of a bundle.
field_ui_field_overview_form_submit Form submission handler for field_ui_field_overview_form().
field_ui_field_overview_form_validate Form validation handler for field_ui_field_overview_form().
field_ui_field_overview_row_region Returns the region to which a row in the 'Manage fields' screen belongs.
field_ui_field_settings_form Form constructor for the field settings edit page.
field_ui_field_settings_form_submit Form submission handler for field_ui_field_settings_form().
field_ui_field_type_options Returns an array of field_type options.
field_ui_formatter_options Returns an array of formatter options for a field type.
field_ui_get_destinations Extracts next redirect path from an array of multiple destinations.
field_ui_inactive_message Displays a message listing the inactive fields of a given bundle.
field_ui_next_destination Returns the next redirect path in a multipage sequence.
field_ui_table_pre_render Pre-render callback for field_ui_table elements.
field_ui_widget_type_form Form constructor for the widget selection form.
field_ui_widget_type_form_submit Form submission handler for field_ui_widget_type_form().
field_ui_widget_type_options Returns an array of widget type options for a field type.
theme_field_ui_table Returns HTML for Field UI overview tables.
_field_ui_add_default_view_mode_settings Populates display settings for a new view mode from the default view mode.
_field_ui_field_name_exists Render API callback: Checks if a field machine name is taken.
_field_ui_field_overview_form_validate_add_existing Validates the 'add existing field' row of field_ui_field_overview_form().
_field_ui_field_overview_form_validate_add_new Validates the 'add new field' row of field_ui_field_overview_form().
_field_ui_reduce_order Determines the rendering order of an array representing a tree.

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