fix(datefield,datetimefield): not rendered fields

Signed-off-by: Thierry Bugier <tbugier@teclib.com>

Author: btry

inc/fields/datefield.class.php

@@ -79,7 +79,7 @@ public function getRenderedHtml($canEdit = true) {
       $rand      = mt_rand();
       $fieldName = 'formcreator_field_' . $id;
 
-      Html::showDateField($fieldName, [
+      $html .= Html::showDateField($fieldName, [
          'value'   => (strtotime($this->value) != '') ? $this->value : '',
          'rand'    => $rand,
          'display' => false,

inc/fields/datetimefield.class.php

@@ -48,7 +48,7 @@ public function getRenderedHtml($canEdit = true) {
       $rand      = mt_rand();
       $fieldName = 'formcreator_field_' . $id;
 
-      Html::showDateTimeField($fieldName, [
+      $html .= Html::showDateTimeField($fieldName, [
          'value'   => strtotime($this->value) != '' ? $this->value : '',
          'rand'    => $rand,
          'display' => false,