diff --git a/includes/field_ui.inc b/includes/field_ui.inc
index 3d5a859..1ecb230 100644
--- a/includes/field_ui.inc
+++ b/includes/field_ui.inc
@@ -396,7 +396,7 @@ function ds_field_ui_layouts_save($form, FormStateInterface $form_state) {
     $record['layout']['settings']['attributes'] = '';
     $record['layout']['settings']['link_attribute'] = FALSE;
     $record['layout']['settings']['link_custom'] = '';
-    $fields = _ds_sort_fields($form_state->getValue('fields'), 'weight');
+    $fields = _ds_sort_fields((array) $form_state->getValue('fields'), 'weight');
     foreach ($fields as $field_key => $field) {
 
       // Ignore new fieldgroup, new field or existing field.
@@ -423,7 +423,7 @@ function ds_field_ui_layouts_save($form, FormStateInterface $form_state) {
   elseif (!empty($layout)) {
     $save_display = TRUE;
 
-    $fields = _ds_sort_fields($form_state->getValue('fields'), 'weight');
+    $fields = _ds_sort_fields((array) $form_state->getValue('fields'), 'weight');
 
     foreach ($fields as $key => $field) {
       // Make sure to hide hidden fields.