import 'package:test_sa/models/lookup.dart'; class CalibrationTool{ Lookup assetsNumber; DateTime dataOfTesting; CalibrationTool({ this.assetsNumber, this.dataOfTesting, }); Map toMap() { return { if(assetsNumber != null) 'assetsSN': (assetsNumber?.id).toString(), if(dataOfTesting != null) 'dataOfTesting': (dataOfTesting.millisecondsSinceEpoch ~/ 1000).toString(), }; } factory CalibrationTool.fromMap(Map map) { return CalibrationTool( assetsNumber: Lookup.fromJson(map['assetsSN']), dataOfTesting: map['dataOfTesting'] == null || map['dataOfTesting'] == "" ? null : DateTime.fromMillisecondsSinceEpoch(int.tryParse(map['dataOfTesting']) * 1000), ); } }