Recycler

 private void setupMemberRecycler(){
        Helper.getUserModel(new HelperListener() {
            @Override
            public void onFinish(UserModel currentModel) {
                if(currentModel.getSynchronizedUsers() != null) {
                    userModels = new ArrayList<>();
                    userModels.add(currentModel);
                    for (String item : currentModel.getSynchronizedUsers()) {
                        Helper.getUserModel(item, new HelperListener() {
                            @Override
                            public void onFinish(UserModel userModel) {
                                userModels.add(userModel);
                            }

                            @Override
                            public void onFinish(DatabaseReference databaseReference) {

                            }
                        });
                    }
                    if((userModels.size()-1) == currentModel.getSynchronizedUsers().size()){
                        syncMemberAdapter = new SyncMemberAdapter(TrackerActivity.this, userModels);
                        memberRecyclerView.setAdapter(syncMemberAdapter);
                        memberRecyclerView.smoothScrollToPosition(0);
                    }

                } else {
                    userModels = new ArrayList<>();
                    userModels.add(currentModel);
                    syncMemberAdapter = new SyncMemberAdapter(TrackerActivity.this, userModels);
                    memberRecyclerView.setAdapter(syncMemberAdapter);
                    memberRecyclerView.smoothScrollToPosition(0);
                }
            }

            @Override
            public void onFinish(DatabaseReference databaseReference) {

            }
        });
    }