android - 我想在Flutter中将数据添加到Firebase中的嵌套子级中？

Question

数据样本

database
|__news
    |__category1
    |    |
    |    |__post1
    |    |    |__text: "Lorem ipsum 1"
    |    |    |__title: "Title of post1"
    |    |__post2
    |    |    |__text: "Lorem ipsum 2"
    |    |    |__title: "Title of post2"
    |    |__description: "description text"
    |    |__id: "id of category"
    |    .
    |    .
    |
    |__category2
    |    |
    |    |__post34
    |    |    |__text: "Lorem ipsum 34"
    |    |    |__title: "Title of post34"
    |    .
    |    .

现在，我有一个在Firebase中创建数据的简单函数是:

 void createRecord() {
    databaseReference.child("post1").set({
      'text': 'Mastering EJB',
      'title': 'Programming Guide for J2EE'
    });

我的问题是我想在 =>news->category1>[posts]处添加数据
所以我应该怎么做才能迭代到 post1

Answer 1

要将相同的数据写入/news/category1/post1，您需要执行以下操作:

databaseReference.child("/news/category1/post1").set({
  'text': 'Mastering EJB',
  'title': 'Programming Guide for J2EE'
});

作为辅助节点，您似乎正在嵌套类别和帖子，这与Firebase对 avoid nesting data和 keeping data structures flat的建议背道而驰。
建议不要使用一棵树，而建议:

database
|__news
    |__category1
    |    |
    |    |__post1
    |    |    |__text: "Lorem ipsum 1"
    |    |    |__title: "Title of post1"
    |    |__post2
    |    |    |__text: "Lorem ipsum 2"
    |    |    |__title: "Title of post2"
    |    .
    |    .
    |
    |__category2
    |    |
    |    |__post34
    |    |    |__text: "Lorem ipsum 34"
    |    |    |__title: "Title of post34"
    |    .
    |    .
|__news_categories
    |__category1
    |    |__description: "description text"
    |    |__id: "id of category"
    |
    |__category2
    |    |__description: "description text of category 2"
    |    |__id: "id of category2"
    |    .
    |    .