/**
  * {@inheritdoc}
  */
 public function elementValidate($element, FormStateInterface $form_state, $form)
 {
     $auto_create = $this->getSelectionHandlerSetting('auto_create');
     // If a value was entered into the autocomplete.
     $value = NULL;
     if (!empty($element['#value'])) {
         // Take "label (entity id)', match the id from parenthesis.
         // @todo: Lookup the entity type's ID data type and use it here.
         // https://drupal.org/node/2107249
         if ($this->isContentReferenced() && preg_match("/.+\\((\\d+)\\)/", $element['#value'], $matches)) {
             $value = $matches[1];
         } elseif (preg_match("/.+\\(([\\w.]+)\\)/", $element['#value'], $matches)) {
             $value = $matches[1];
         }
         if ($value === NULL) {
             // Try to get a match from the input string when the user didn't use the
             // autocomplete but filled in a value manually.
             $handler = \Drupal::service('plugin.manager.entity_reference.selection')->getSelectionHandler($this->fieldDefinition);
             $value = $handler->validateAutocompleteInput($element['#value'], $element, $form_state, $form, !$auto_create);
         }
         if (!$value && $auto_create && count($this->getSelectionHandlerSetting('target_bundles')) == 1) {
             // Auto-create item. See
             // \Drupal\Core\Field\Plugin\Field\FieldType\EntityReferenceItem::presave().
             $value = array('target_id' => NULL, 'entity' => $this->createNewEntity($element['#value'], $element['#autocreate_uid']), '_weight' => $element['#weight']);
             // Change the element['#parents'], so in form_set_value() we
             // populate the correct key.
             array_pop($element['#parents']);
         }
     }
     form_set_value($element, $value, $form_state);
 }

 /**
  * Form element validation handler for 'name' in form_test_validate_form().
  */
 public function validateName(&$element, FormStateInterface $form_state)
 {
     $triggered = FALSE;
     if ($form_state->getValue('name') == 'element_validate') {
         // Alter the form element.
         $element['#value'] = '#value changed by #element_validate';
         // Alter the submitted value in $form_state.
         form_set_value($element, 'value changed by form_set_value() in #element_validate', $form_state);
         $triggered = TRUE;
     }
     if ($form_state->getValue('name') == 'element_validate_access') {
         $form_state->set('form_test_name', $form_state->getValue('name'));
         // Alter the form element.
         $element['#access'] = FALSE;
         $triggered = TRUE;
     } elseif ($form_state->has('form_test_name')) {
         // To simplify this test, just take over the element's value into $form_state.
         form_set_value($element, $form_state->get('form_test_name'), $form_state);
         $triggered = TRUE;
     }
     if ($triggered) {
         // Output the element's value from $form_state.
         drupal_set_message(t('@label value: @value', array('@label' => $element['#title'], '@value' => $form_state->getValue('name'))));
         // Trigger a form validation error to see our changes.
         $form_state->setErrorByName('');
     }
 }

 /**
  * Form element validation handler for 'name' in form_test_validate_form().
  */
 public function validateName(&$element, &$form_state)
 {
     $triggered = FALSE;
     if ($form_state['values']['name'] == 'element_validate') {
         // Alter the form element.
         $element['#value'] = '#value changed by #element_validate';
         // Alter the submitted value in $form_state.
         form_set_value($element, 'value changed by form_set_value() in #element_validate', $form_state);
         $triggered = TRUE;
     }
     if ($form_state['values']['name'] == 'element_validate_access') {
         $form_state['storage']['form_test_name'] = $form_state['values']['name'];
         // Alter the form element.
         $element['#access'] = FALSE;
         $triggered = TRUE;
     } elseif (!empty($form_state['storage']['form_test_name'])) {
         // To simplify this test, just take over the element's value into $form_state.
         form_set_value($element, $form_state['storage']['form_test_name'], $form_state);
         $triggered = TRUE;
     }
     if ($triggered) {
         // Output the element's value from $form_state.
         drupal_set_message(t('@label value: @value', array('@label' => $element['#title'], '@value' => $form_state['values']['name'])));
         // Trigger a form validation error to see our changes.
         form_set_error('', $form_state);
     }
 }

/**
 * Form submit for da_vinci_form_system_theme_settings_alter().
 */
function da_vinci_form_system_theme_settings_submit($form, &$form_state)
{
    $exclude_css = array_filter(array_map('trim', explode("\n", $form_state['values']['css_exclude'])));
    $exclude_js = array_filter(array_map('trim', explode("\n", $form_state['values']['js_exclude'])));
    form_set_value(array('#parents' => array('css_exclude')), $exclude_css, $form_state);
    form_set_value(array('#parents' => array('js_exclude')), $exclude_js, $form_state);
}

/**
 * Element validate; Set the value of the providers.
 */
function entityreference_prepopulate_providers_validate($element, &$form_state)
{
    $value = $form_state['values']['instance']['settings']['behaviors']['prepopulate']['providers']['enabled'];
    // Sort the value by the weight.
    uasort($value, 'drupal_sort_weight');
    form_set_value($element, $value, $form_state);
}

 /**
  * Element validation helper.
  */
 public static function multipleValidate($element, FormStateInterface $form_state)
 {
     $values = array_map('trim', explode(',', $element['#value']));
     $items = array();
     foreach ($values as $value) {
         $items[] = array('value' => $value);
     }
     form_set_value($element, $items, $form_state);
 }

function drupalexp_form_system_theme_settings_validate(&$form, &$form_state)
{
    $drupalexp_layouts = '';
    $i = 0;
    while (isset($form_state['input']['dexp_layout_' . $i])) {
        $drupalexp_layouts .= $form_state['input']['dexp_layout_' . $i];
        $i++;
    }
    form_set_value($form['layout_settings']['drupalexp_layouts'], $drupalexp_layouts, $form_state);
}

 /**
  * @todo
  */
 function edit_form_validate(&$form, &$form_state)
 {
     parent::edit_form_validate($form, $form_state);
     $values = $form_state['values'];
     if ($values['parent'] == '_none') {
         form_set_value(array('#parents' => array('parent')), '', $form_state);
     } else {
         form_set_value(array('#parents' => array('mode')), DELTA_PRESERVE, $form_state);
     }
 }

 /**
  * {@inheritdoc}
  */
 public function validateForm(array &$form, array &$form_state)
 {
     if ($form_state['values']['name'] == 'validate') {
         // Alter the form element.
         $form['name']['#value'] = '#value changed by #validate';
         // Alter the submitted value in $form_state.
         form_set_value($form['name'], 'value changed by form_set_value() in #validate', $form_state);
         // Output the element's value from $form_state.
         drupal_set_message(t('@label value: @value', array('@label' => $form['name']['#title'], '@value' => $form_state['values']['name'])));
         // Trigger a form validation error to see our changes.
         form_set_error('', $form_state);
     }
 }

/**
 * Form element validation handler for validating the primary region setting for zones.
 */
function alpha_theme_settings_validate_primary(&$element, &$form_state)
{
    if ($element['#value'] != '_none') {
        $values = $form_state['values'];
        if ($values['alpha_region_' . $element['#value'] . '_zone'] != $element['#zone']) {
            form_set_value($element, NULL, $form_state);
        } else {
            $sum = 0;
            foreach ($form_state['regions'] as $region => $item) {
                if ($values['alpha_region_' . $region . '_zone'] == $element['#zone']) {
                    $sum += $values['alpha_region_' . $region . '_columns'];
                    $sum += $values['alpha_region_' . $region . '_prefix'];
                    $sum += $values['alpha_region_' . $region . '_suffix'];
                }
            }
            if ($sum > $values['alpha_zone_' . $element['#zone'] . '_columns']) {
                form_error($element, t('You have specified the %region region as the primary region for the %zone zone but the summed region width is greater than the number of available columns for that zone.', array('%region' => $form_state['regions'][$element['#value']]['name'], '%zone' => $form_state['zones'][$element['#zone']]['name'])));
            }
        }
    }
}

 /**
  * {@inheritdoc}
  */
 public function elementValidate($element, &$form_state, $form)
 {
     $value = array();
     // If a value was entered into the autocomplete.
     $handler = \Drupal::service('plugin.manager.entity_reference.selection')->getSelectionHandler($this->fieldDefinition);
     $bundles = entity_get_bundles($this->getFieldSetting('target_type'));
     $auto_create = $this->getSelectionHandlerSetting('auto_create');
     if (!empty($element['#value'])) {
         $value = array();
         foreach (Tags::explode($element['#value']) as $input) {
             $match = FALSE;
             // Take "label (entity id)', match the ID from parenthesis when it's a
             // number.
             if (preg_match("/.+\\((\\d+)\\)/", $input, $matches)) {
                 $match = $matches[1];
             } elseif (preg_match("/.+\\(([\\w.]+)\\)/", $input, $matches)) {
                 $match = $matches[1];
             } else {
                 // Try to get a match from the input string when the user didn't use
                 // the autocomplete but filled in a value manually.
                 $match = $handler->validateAutocompleteInput($input, $element, $form_state, $form, !$auto_create);
             }
             if ($match) {
                 $value[] = array('target_id' => $match);
             } elseif ($auto_create && (count($this->getSelectionHandlerSetting('target_bundles')) == 1 || count($bundles) == 1)) {
                 // Auto-create item. See
                 // \Drupal\Core\Field\Plugin\Field\FieldType\EntityReferenceItem::presave().
                 $value[] = array('target_id' => NULL, 'entity' => $this->createNewEntity($input, $element['#autocreate_uid']));
             }
         }
     }
     // Change the element['#parents'], so in form_set_value() we
     // populate the correct key.
     array_pop($element['#parents']);
     form_set_value($element, $value, $form_state);
 }

 /**
  * Form validation handler for widget elements.
  *
  * @param array $element
  *   The form element.
  * @param array $form_state
  *   The form state.
  */
 public static function validateElement(array $element, array &$form_state)
 {
     if ($element['#required'] && $element['#value'] == '_none') {
         \Drupal::formBuilder()->setError($element, $form_state, t('!name field is required.', array('!name' => $element['#title'])));
     }
     // Massage submitted form values.
     // Drupal\Core\Field\WidgetBase::submit() expects values as
     // an array of values keyed by delta first, then by column, while our
     // widgets return the opposite.
     if (is_array($element['#value'])) {
         $values = array_values($element['#value']);
     } else {
         $values = array($element['#value']);
     }
     // Filter out the 'none' option. Use a strict comparison, because
     // 0 == 'any string'.
     $index = array_search('_none', $values, TRUE);
     if ($index !== FALSE) {
         unset($values[$index]);
     }
     // Transpose selections from field => delta to delta => field.
     $items = array();
     foreach ($values as $value) {
         $items[] = array($element['#key_column'] => $value);
     }
     form_set_value($element, $items, $form_state);
 }

function devis_user_profile_form_validate($form, &$form_state)
{
    // This is a check in case the javascript is disabled for whatever reason.
    if (isset($form['profile_budget_profile']['field_active_regions_belgium'])) {
        $belgium = FALSE;
        $count = 0;
        // Check if Belgium is selected among the choices.
        $lang = $form['profile_budget_profile']['field_active_regions_belgium']['#language'];
        foreach ($form_state['values']['profile_budget_profile']['field_active_regions_belgium'][$lang] as $k => $val) {
            $count++;
            if ($val['value'] == 'BEL') {
                $belgium = TRUE;
            }
        }
        // If Belgium is selected, then asign only Belgium as the value.
        if ($belgium && $count > 1) {
            $new_value = array($lang => array(0 => array('value' => 'BEL')));
            $value['#parents'] = array('profile_budget_profile', 'field_active_regions_belgium');
            form_set_value($value, $new_value, $form_state);
        }
    }
    if (isset($form_state['values']['mail'])) {
        // E-mail check for duplicate user.
        $user_check = user_load_by_mail($form_state['values']['mail']);
        if ($user_check && $form['#user']->uid != $user_check->uid) {
            $site_name = variable_get('site_name', '3devis.be');
            form_set_error('mail', t('The specified email is already registered in !site_name.', array('!site_name' => $site_name)));
        }
        // E-mail check.
        if (!valid_email_address($form_state['values']['mail'])) {
            form_set_error('mail', t('The specified email is not a valid email.'));
        }
    }
    devis_field_phone_belgium_validate($form, $form_state);
    devis_field_tva_validate($form, $form_state);
}

 /**
  * {@inheritdoc}
  */
 public function validate(array $form, FormStateInterface $form_state)
 {
     parent::validate($form, $form_state);
     form_set_value($form['id'], $this->targetEntityTypeId . '.' . $form_state['values']['id'], $form_state);
 }

function _agency_1_theme_settings_map($form, &$form_state)
{
    $validators = array('file_validate_is_image' => array());
    $file = file_save_upload('background_file', $validators);
    $map_file = file_save_upload('footer_contact_us_map_image', $validators);
    //Map image
    if (isset($map_file)) {
        // File upload was attempted.
        if ($map_file) {
            // Move the file, into the Drupal file system
            if ($map_filename = file_unmanaged_copy($map_file->uri, 'public://background_images', FILE_EXISTS_RENAME)) {
                //resize, if necessary
                $map_resized = image_load($map_file->uri);
                list($map_width, $map_height) = getimagesize($map_file->uri);
                if ($map_width > 150 || $map_height > 150) {
                    if ($map_width / $map_height >= 1) {
                        image_scale($map_resized, 150);
                    } else {
                        image_scale($map_resized, null, 150);
                    }
                    image_save($map_resized, $map_filename, FILE_EXISTS_RENAME);
                    $map_resized->status = FILE_STATUS_PERMANENT;
                    drupal_set_message('Uploaded image was greater than 150px.  Image has been resized.');
                }
                //end resize
                unset($form['footer_contact_us']['settings']['footer_contact_us_map_path']);
                $form['footer_contact_us']['settings']['footer_contact_us_map_path']['#value'] = $map_filename;
                $form['footer_contact_us_map_path']['#parents'] = array('footer_contact_us_map_path');
                form_set_value($form['footer_contact_us_map_path'], file_create_url($map_filename), $form_state);
                watchdog('Theme Settings', 'New Footer Map Image uploaded: ' . file_create_url($map_filename));
                drupal_set_message('Map Image uploaded.  URL: ' . file_create_url($map_filename));
            } else {
                form_set_error('file', t('Failed to write the uploaded file the site\'s file folder.'));
            }
        } else {
            // File upload failed.
            form_set_error('background_file', t('The image could not be uploaded.'));
        }
    }
}

 /**
  * Fill value in any field of the form. It first checks if corresponding key
  * exists in the form array. If yes, it finds out its #tree value and that of
  * its parents and sets form_state appropriately. If it doesn't find the key
  * in the form array, then it sets the values in form_state at the top level.
  *
  * @param string|array $field_name
  *   Field name if it is present at top-level form element. If it is not at
  *   the top-level form element, then provide an array.
  * @param string|int|array $values
  *   Value that needs to be filled.
  *
  * @return Response
  *   Response object.
  */
 public function fillValues($field_name, $values)
 {
     if (is_string($field_name)) {
         $field_name = array($field_name);
     }
     $response = $this->getTreeKeys($field_name);
     if (!$response->getSuccess()) {
         $element['#parents'] = $field_name;
     } else {
         $element['#parents'] = $response->getVar();
     }
     form_set_value($element, $values, $this->form_state);
     return new Response(TRUE, $values, "");
 }

 /**
  * {@inheritdoc}
  */
 public function validateForm(array &$form, FormStateInterface $form_state)
 {
     // Check for empty front page path.
     if ($form_state->isValueEmpty('site_frontpage')) {
         // Set to default "user".
         form_set_value($form['front_page']['site_frontpage'], 'user', $form_state);
     } else {
         // Get the normal path of the front page.
         form_set_value($form['front_page']['site_frontpage'], $this->aliasManager->getPathByAlias($form_state->getValue('site_frontpage')), $form_state);
     }
     // Validate front page path.
     if (!$this->pathValidator->isValid($form_state->getValue('site_frontpage'))) {
         $form_state->setErrorByName('site_frontpage', $this->t("The path '%path' is either invalid or you do not have access to it.", array('%path' => $form_state->getValue('site_frontpage'))));
     }
     // Get the normal paths of both error pages.
     if (!$form_state->isValueEmpty('site_403')) {
         form_set_value($form['error_page']['site_403'], $this->aliasManager->getPathByAlias($form_state->getValue('site_403')), $form_state);
     }
     if (!$form_state->isValueEmpty('site_404')) {
         form_set_value($form['error_page']['site_404'], $this->aliasManager->getPathByAlias($form_state->getValue('site_404')), $form_state);
     }
     // Validate 403 error path.
     if (!$form_state->isValueEmpty('site_403') && !$this->pathValidator->isValid($form_state->getValue('site_403'))) {
         $form_state->setErrorByName('site_403', $this->t("The path '%path' is either invalid or you do not have access to it.", array('%path' => $form_state->getValue('site_403'))));
     }
     // Validate 404 error path.
     if (!$form_state->isValueEmpty('site_404') && !$this->pathValidator->isValid($form_state->getValue('site_404'))) {
         $form_state->setErrorByName('site_404', $this->t("The path '%path' is either invalid or you do not have access to it.", array('%path' => $form_state->getValue('site_404'))));
     }
     parent::validateForm($form, $form_state);
 }

 function edit_form_validate(&$form, &$form_state)
 {
     $export_key = $this->plugin['export']['key'];
     // When adding a machine name, the entity/bundle are left off so the user
     // does not have to deal with it. We put it back here behind the scenes.
     $name = $form_state['values'][$export_key];
     form_set_value($form['info'][$export_key], implode(':', array($this->entity_handler->entity_type, $this->entity_bundle, $name)), $form_state);
 }

/**
 * Helper function for install_settings_validate.
 */
function _install_settings_form_validate($database, $settings_file, &$form_state, $form = NULL)
{
    global $databases;
    // Verify the table prefix
    if (!empty($database['prefix']) && is_string($database['prefix']) && !preg_match('/^[A-Za-z0-9_.]+$/', $database['dprefix'])) {
        form_set_error('db_prefix', st('The database table prefix you have entered, %db_prefix, is invalid. The table prefix can only contain alphanumeric characters, periods, or underscores.', array('%db_prefix' => $db_prefix)), 'error');
    }
    if (!empty($database['port']) && !is_numeric($database['port'])) {
        form_set_error('db_port', st('Database port must be a number.'));
    }
    // Check database type
    $database_types = drupal_detect_database_types();
    $driver = $database['driver'];
    if (!isset($database_types[$driver])) {
        form_set_error('driver', st("In your %settings_file file you have configured @drupal to use a %driver server, however your PHP installation currently does not support this database type.", array('%settings_file' => $settings_file, '@drupal' => drupal_install_profile_name(), '%driver' => $database['driver'])));
    } else {
        if (isset($form)) {
            form_set_value($form['_database'], $database, $form_state);
        }
        $class = "DatabaseInstaller_{$driver}";
        $test = new $class();
        $databases = array('default' => array('default' => $database));
        $return = $test->test();
        if (!$return || $test->error) {
            if (!empty($test->success)) {
                form_set_error('db_type', st('In order for Drupal to work, and to continue with the installation process, you must resolve all permission issues reported above. We were able to verify that we have permission for the following commands: %commands. For more help with configuring your database server, see the <a href="http://drupal.org/node/258">Installation and upgrading handbook</a>. If you are unsure what any of this means you should probably contact your hosting provider.', array('%commands' => implode($test->success, ', '))));
            } else {
                form_set_error('driver', '');
            }
        }
    }
}

/**
 * Form API validate for install_settings form.
 */
function install_settings_form_validate($form, &$form_state)
{
    form_set_value($form['_database'], $form_state['values'], $form_state);
    $errors = install_database_errors($form_state['values'], $form_state['values']['settings_file']);
    foreach ($errors as $name => $message) {
        form_set_error($name, $message);
    }
}