add check for empty vector in getMessageType function

Signed-off-by: Emre <[email protected]>

Author: EmreK03

rviz_common/include/rviz_common/properties/ros_topic_property.hpp

@@ -62,7 +62,7 @@ class RVIZ_COMMON_PUBLIC RosTopicProperty : public EditableEnumProperty
   void setMessageTypes(const std::vector<QString> & message_types);
 
   QString getMessageType() const
-  {return message_types_.front();}
+  {return message_types_.empty() ? QString() : message_types_.front();}
 
   std::vector<QString> getMessageTypes() const
   {return message_types_;}