Flutter Hive 不保存子类

Question

假设我有以下 3 个类：

class Human{

    String name;

    Human({this.name});

}

class Student extends Human{

    int id;

    Student(this.id): super(name: name);
}

class Proffessor extends Human{

    int age;

    Proffessor(this.age): super(name: name);
}

class Abc {

    List<Human> humans;

    Abc(this.humans);
//Just Imagine my humans List consists of Proffessors AND Students (both Subtypes of human)
}

我正在使用以下依赖项 hive_generator: ^1.1.1 hive_flutter：^1.1.0 蜂巢：^2.0.4 dev_dependencies： build_runner：^2.1.4 基本上，我有一个由教授和学生组成的列表，但是当这个列表被保存并稍后从 Hive 中检索时，该列表中的所有对象都被强制转换为人类

Abc read(BinaryReader reader) {
    final numOfFields = reader.readByte();

    final fields = <int, dynamic>{
        for (int i = 0; i < numOfFields; i++) 
            reader.readByte(): reader.read(),  
    };

    return Abc(
        fields[0] as int,
        fields[1] as String?,
        fields[2] as String?,
        (fields[3] as List?)?.cast<Human>(), // I need the Elements in this List as Student / Proffessor not Human
        fields[4] as int,
    );}

//基本上我正在丢失信息，因为适配器将学生和教授转换为人类

有解决办法吗？如果不是，那么 hive 的下一个最佳替代品是什么？

Answer 1

我不知道到底发生了什么。我就是这样用蜂巢的

@HiveType(typeId: 1)
class FavouriteSingerDao extends HiveObject{

 @HiveField(0)
  int id;

 @HiveField(2)
  String singerName;

 @HiveField(3)
  String singerTag;
 }

---

static Future addFavouriteSinger(SingerMapper favouriteSinger) async {
    final transaction = FavouriteSingerDao()
      ..id = favouriteSinger.id
      ..singerName = favouriteSinger.singerName
      ..singerTag = favouriteSinger.singerTag;

    final box = BoxesUtils.getFavouriteSingers();
    box.put(favouriteSinger.id, transaction).then(
          (value) => Fluttertoast.showToast(
        msg: TEXT_ADD_SUCCESS,
      ),
    );
  }

  static List<FavouriteSingerDao> getFavouriteSingerItems() {
    final box = BoxesUtils.getFavouriteSingers();
    List<FavouriteSingerDao> favouriteSingers =
    box.values.toList().cast<FavouriteSingerDao>();
    return favouriteSingers;
  }