addMap method Null safety
Implementation
void addMap(Map<String, T> dataMap, int? ts) {
if (dataMap.isEmpty) return;
final time = ts ?? DateTime.now().millisecondsSinceEpoch;
dataMap.forEach((k, v) => addWithKey(k, v, time));
}
void addMap(Map<String, T> dataMap, int? ts) {
if (dataMap.isEmpty) return;
final time = ts ?? DateTime.now().millisecondsSinceEpoch;
dataMap.forEach((k, v) => addWithKey(k, v, time));
}