如何实现GreenDao表继承 [英] how to implement table inheritance in GreenDao

问题描述

我一直在试图创造一个所有表，以继承某个元素数据库不得不可能性有元数据。

I've been trying to create a database where all the tables inherit a certain element in order to have to possibility to have meta-data.

有对我的模型生成器加入所有的表声明此行

there for I added in the model generator in all the table declarations this line:

public Entity addSuperEntity(Schema schema) {
     Entity superEntity = schema.addEntity("superEntity");
     superEntity.addIdProperty().primaryKey();
     // SET RELATIONSHIP 1:m TO META DATA
}

public Entity addTable(Schema schema) {
    Entity mEntity = schema.addEntity("MyEntity");
    mEntity.setSuper("superEntity");
    mEntity.addIdProperty().PrimaryKey();
    // REST OF FIELDS
}

问题是：

现在我生成这个对我的Andr​​oid项目后，我怎样才能确保这仍然发生在现实生活中？我现在需要改变什么？

now after I generated this to my Android project, how can I make sure that this still happens in real life? do I need to change anything now?

官方文档没有关于继承的东西。

the official documentation doesn't have anything about inheritance.

推荐答案

继承是支持使用setSuperclass（串）非实体超类。另一种方法是使用实​​现的implementsInterface（字符串）接口。

Inheritance is supported for non-entity super classes using setSuperclass(String). An alternative is implementing interfaces using implementsInterface(String).

我更新了关于继承和接口的新节的一些细节的官方文档：
<一href=\"http://greendao-orm.com/documentation/modelling-entities/\">http://greendao-orm.com/documentation/modelling-entities/

I updated the official docs with some details in the new section on inheritance and interfaces: http://greendao-orm.com/documentation/modelling-entities/

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