在Firestore - Android中获取ArrayList

FirebaseFirestore db = FirebaseFirestore.getInstance();

CollectionReference usersRef = db.collection("users");
Query query = usersRef.whereArrayContains("friends", "John");

query.get().addOnCompleteListener(new OnCompleteListener<QuerySnapshot>() {
    @Override
    public void onComplete(@NonNull Task<QuerySnapshot> task) {
        if (task.isSuccessful()) {
            for (QueryDocumentSnapshot document : task.getResult()) {
                ArrayList<String> friends = (ArrayList<String>) document.get("friends");
                // 处理friends ArrayList
            }
        } else {
            Log.d(TAG, "Error getting documents: ", task.getException());
        }
    }
});