如何从firebase数据库中获取所有子节点？

Question

this is my structure. i am trying to code a scoreboard for my app but i cant get the username & score. i want to safe that username & score in a sorted list to get the top 10.

this is my code: i onle get the usernames.

databaseReference = FirebaseDatabase.getInstance().getReference("Users");
    databaseReference.addValueEventListener(new ValueEventListener() {
            @Override
            public void onDataChange(DataSnapshot dataSnapshot) {
                Userlist = new ArrayList<String>();
                // Result will be holded Here

                for (DataSnapshot dsp : dataSnapshot.getChildren()) {
                    for (DataSnapshot as : dataSnapshot.getChildren()) {
                        String userkey= as.getKey();
                        Userlist.add(userkey); //add result into array list

                    }
                }

                un.setText(Userlist.get(2));

            }

        @Override
        public void onCancelled(DatabaseError error) {

        }
    });

Answer 1

Try the following:

databaseReference = FirebaseDatabase.getInstance().getReference("Users");
databaseReference.addValueEventListener(new ValueEventListener() {
        @Override
        public void onDataChange(DataSnapshot dataSnapshot) {
            Userlist = new ArrayList<String>();
            // Result will be holded Here

            for (DataSnapshot dsp : dataSnapshot.getChildren()) {
                    String userkey  = dsp.getKey();
                    String scores   = dsp.child("scorehigh").getValue().toString();
                    Userlist.add(userkey); //add result into array list
                }
            }

            un.setText(Userlist.get(2));

        }

    @Override
    public void onCancelled(DatabaseError error) {

    }
});

The reference is at Users then you need to loop twice to be able to access the attributes scorehigh and username