addIdMesg method
Implementation
void addIdMesg(DeveloperDataIdMesg mesg) {
int? index = mesg.developerDataIndex;
if (index == null) return;
_developerDataIdMesgs[index] = mesg;
// Remove all fields currently associated with this developer
_fieldDescriptionMesgs.removeWhere(
(key, value) => key.developerDataIndex == index,
);
}