Firebase for Android, How can I loop through a child (for each child = x do y)

Question

This is what my test looks like:

I won't use the fields above, it's just a dummy. But I would like to go through all the children on "users" and for each email return a:

System.out.println(emailString); 

The only way I found of listing an object is using firebaseAdapter, is there another way of doing it?

Answer 1

The easiest way is with a ValueEventListener.

    FirebaseDatabase.getInstance().getReference().child("users")             .addListenerForSingleValueEvent(new ValueEventListener() {                 @Override                 public void onDataChange(DataSnapshot dataSnapshot) {                     for (DataSnapshot snapshot : dataSnapshot.getChildren()) {                         User user = snapshot.getValue(User.class);                         System.out.println(user.email);                     }                 }                 @Override                 public void onCancelled(DatabaseError databaseError) {                 }             }); 

The User class can be defined like this:

class User {   private String email;   private String userId;   private String username;   // getters and setters... } 

Answer 2

FirebaseDatabase database = FirebaseDatabase.getInstance(); DatabaseReference myRef = database.getReference(); myRef.addValueEventListener(new ValueEventListener() {  @Override  public void onDataChange(DataSnapshot dataSnapshot) {     for(DataSnapshot item_snapshot:dataSnapshot.getChildren()) {        Log.d("item id ",item_snapshot.child("item_id").getValue().toString());       Log.d("item desc",item_snapshot.child("item_desc").getValue().toString());      }   } }