QuerySnapshot 指向多个 QueryDocumentSnapshot 实例.

从 QueryDocumentSnapshot，你可以得到它的集合:

From a QueryDocumentSnapshot, you can get the collection it's from with:

snapshot.getRef().getParent()

然后父 DocumentReference 是:

snapshot.getRef().getParent().getParent()

所以要获得父文档的子集合:

So to get a subscollection of the parent document with:

snapshot.getRef().getParent().getParent().collection("name_of_subcollection")

是的，我同意……这本来可以更具可读性.:)

Yes, I agree... that could've been a bit more readable. :)