java - 使用 ObjectBox 存储一对多关系列表？

Question

我从服务器得到如下所示的 json:

  { "customers": [
    {
        "customer_name": "name1",
        "orders_list": [
            {
                "order_id": "1111111",
                "order_type": "a",
                "order_date": "11/02/2020 "
            },
            {
                "order_id": "1111112",
                "order_type": "b",
                "order_date": "11/02/2020 "
            },
            {
                "order_id": "1111113",
                "order_type": "c",
                "order_date": "11/02/2020 "
            }
        ]
    },
    //more customers
]

}

我使用 Retrofit 获取它并希望使用 Objectbox 存储它。

客户实体:

  @Entity
public class Customer {

    @Id long id;

    @SerializedName("customer_name")
    private String  customer_name;

    @SerializedName("array_of_matchs")
    @Transient
    public List<Order> orders_list;

    @Backlink
    public ToMany<Order> orders;

   //constructor , getters , setters ,...
}

订单实体:

公开课订单{

    @Id
    public long id;

    @SerializedName("order_id")
    private int  order_id;

    @SerializedName("order_type")
    private String  order_type;

    @SerializedName("order_date")
    private String  order_date;

    public ToOne<Customer> customer;
  //constructor , getters , setters ,...
}

Gson 转换器返回包含所有订单的客户的列表。我尝试按如下方式存储客户:

  customersBox.put(list_of_customers_get_from_retrofit);

和订单:

for (Customer each_customer : list_of_customers_get_from_retrofit ) {
      orderBox.put(each_customer.orders_list);
}

然后当我用 Data Browser 选中复选框时，所有 customerToOneRelationId 设置为 0 。这有什么问题吗？

在这种情况下，我们如何在客户与其订单列表之间建立关系？如何正确存储订单？

Answer 1

我必须手动设置目标:

 for (Customer each_customer : list_of_customers_get_from_retrofit ) {
     for (Order each_order : each_customer.orders_list ) {
       each_order.customer.setTarget(each_customer);
       orderBox.put(each_order);
     }
}

感谢这个repository (这对于像我这样的 Objectbox 新手很有用)。