Firebase按键从子项检索数据

Question

Now what I am trying to do is to get all the children having category value of shop

I have tried this code

Firebase ref = new Firebase("https://top-africa.firebaseio.com/businesses/);
ref.orderByChild("category").equalTo("shop");
        ref.addChildEventListener(new ChildEventListener() {
            @Override
            public void onChildAdded(DataSnapshot dataSnapshot,  String s) {
                Object ob = dataSnapshot.getValue();
                System.out.println("There are " + dataSnapshot.getKey() + " blog posts==" + dataSnapshot.getValue());
            }
 });

but when I look at the log it printed out all 10 children whereas I suppose I would retrieve only one because there was only one value for category shop .

I don't know what I am missing. Could you please help me to solve the issue?

Answer 1

your reference is pointing to bussiness, so use query to fetch the data with condition

Query mQuery = ref.orderByChild("category").equalTo("Shop");
mQuery.addChildEventListener(new ChildEventListener() {
            @Override
            public void onChildAdded(DataSnapshot dataSnapshot,  String s) {
                Object ob = dataSnapshot.getValue();
                System.out.println("There are " + dataSnapshot.getKey() + " blog posts==" + dataSnapshot.getValue());
            }
 });