javascript - 如何从 Firestore 查询 Expo 中嵌套集合的数据

Question

[这是文档结构][1] 我需要从 Firestore 中的嵌套集合 (journal/userID/entries) 中获取数据到平面列表 (React Native/Expo) 中。这是我的代码片段：

function TextEntry() {
  const ref =
    firebase
      .firestore()
      .collection('journal')
      .doc(currentUserUID)
      .collection('entry')

  useEffect(() => {
    return ref.onSnapshot(querySnapshot => {
      const list = [];
      console.log(currentUserUID)
      querySnapshot.forEach(doc => {
        const { title } = doc.data()
        list.push({
          id: doc.id,
          title,
        });
      });

      setTodos(list);

      if (loading) {
        setLoading(false);
      }
    });
  }, []);

  const [todo, setTodo] = useState('');
  const [loading, setLoading] = useState(true);
  const [todos, setTodos] = useState([]);
  let currentUserUID = firebase.auth().currentUser.uid;

  async function addTodo() {
    await ref.add({
      title: todo,
    });
    setTodo('');
  }

标签： javascriptfirebasereact-nativegoogle-cloud-firestoreuse-effect