Dart APIunself_modelActivitytimestamp timestamp property Null safety @JsonDateTime() DateTime timestamp inherited timestamp is the date and time of the Activity by the App. Implementation @JsonDateTime() DateTime get timestamp => throw _privateConstructorUsedError; unself_model unself_model Activity timestamp property Activity class Constructors Activity fromJson Properties accountId appId archiveId copyWith created extra hashCode id labels name runtimeType source sourceId targetId timestamp type updated Methods noSuchMethod toJson toString Operators operator ==