android - Firebase 安卓订购

Question

我无法在日期字段(时间戳)上使用 orderByChild 对结果进行排序

这里是数据结构:

和代码:

  DatabaseReference mMessagesRef = FirebaseDatabase.getInstance().getReference().child("messages")
                .child(mConversationId).getRef()
                .orderByChild("date").getRef();
        mMessagesRef.addListenerForSingleValueEvent(new ValueEventListener() {
            @Override
            public void onDataChange(DataSnapshot dataSnapshot) {

                for(DataSnapshot data: dataSnapshot.getChildren()){

查询返回值，但不是按日期排序，而是按键返回..

Answer 1

Try this:
DatabaseReference mMessagesRef=FirebaseDatabase.getInstance().getReference();
Query queryRef = mMessagesRef.child("messages").orderByChild("date");
queryRef.addListenerForSingleValueEvent(new ValueEventListener() {
            @Override
            public void onDataChange(DataSnapshot dataSnapshot) {

                for(DataSnapshot data: dataSnapshot.getChildren()){