Filter query to populate FirebaseRecyclerAdapter

问题

This is still unclear how to populate FirebaseRecyclerAdapter with custom query.

1. Define a reference. Here: DatabaseReference ref = mDatabase.getReference().child("users");

2. Send it to adapter initAdapter(ref);

3. Define query and set listener. Is it right?

   mAdapter = new FirebaseRecyclerAdapter<User, UserHolder>(User.class,  R.layout.user_row_layout, UserHolder.class, ref) {
   
           @Override
           protected void populateViewHolder(final UserHolder viewHolder, final User model, int position) {
   
               Query query = ref.orderByChild("group").equalTo(uid);
               query.addChildEventListener(new ChildEventListener() {
                   @Override
                   public void onChildAdded(DataSnapshot dataSnapshot, String s) {
                       viewHolder.setName(model.getName());
                       viewHolder.setStatus(getStatus(model.getStatus()));
                   }
   
                   // ...
               };
   

Still showing all data from users. Need just to filter based on uid. Any clues?

回答1:

For those who might have tried to make things over-complicated as me, or working at night, here is solution:

mAdapter = new FirebaseRecyclerAdapter<User, UserHolder>(
               User.class,  
               R.layout.user_row_layout, 
               UserHolder.class,
               ref.orderByChild("group").equalTo(uid)
) {
    @Override
    protected void populateViewHolder(final UserHolder viewHolder, final User model, int position) {

                viewHolder.setName(model.getName());
                viewHolder.setStatus(getStatus(model.getStatus()));
            }

            // ...
        };

Chao!

回答2:

A simple example where I show a rank list with all users:

FirebaseRecyclerAdapter<UserData,RankListViewHolder> adapter = new FirebaseRecyclerAdapter<UserData, RankListViewHolder>
                (
           UserData.class,
           R.layout.rank_item,
           RankListViewHolder.class,
           userRef.child("users").getRef() //--Set here your query
                )
        {
            @Override
protected void populateViewHolder(RankListViewHolder viewHolder, UserData model, int position)
            {
                viewHolder.tvPos.setText(""+position+"º");
                viewHolder.userId = model.getId();
            }
        };

来源：https://stackoverflow.com/questions/41602568/filter-query-to-populate-firebaserecycleradapter