event_class->payload_field_type = ft_struct_create_func();
if (!event_class->payload_field_type) {
BT_LOGE_STR("Cannot create event class's initial payload field type object.");
event_class->payload_field_type = ft_struct_create_func();
if (!event_class->payload_field_type) {
BT_LOGE_STR("Cannot create event class's initial payload field type object.");