#3948 Events: PHP errors when date fields are empty

modules/boonex/events/classes/BxEventsMenuViewActionsAll.php

@@ -27,7 +27,7 @@ class BxEventsMenuViewActionsAll extends BxBaseModGroupsMenuViewActionsAll
     {
         parent::setContentId($iContentId);
 
-        if (!$this->_aContentInfo['date_start'] || !$this->_aContentInfo['date_end'])
+        if (!isset($this->_aContentInfo['date_start']) || !$this->_aContentInfo['date_start'] || !isset($this->_aContentInfo['date_end']) || !$this->_aContentInfo['date_end'])
             return;
 
         $oDateStart = new DateTime('@' . $this->_aContentInfo['date_start']);