private void init() {
    setTitle(App.ctx.getString(R.string.contact_findFriends));
    adapter = new HeaderListAdapter<>(SearchUserItemHolder.class);

    recyclerView.setLayoutManager(new LinearLayoutManager(this));
    recyclerView.setOnLoadDataListener(
        new RefreshableRecyclerView.OnLoadDataListener() {
          @Override
          public void onLoad(int skip, int limit, boolean isRefresh) {
            loadMoreFriend(skip, limit, isRefresh);
          }
        });
    recyclerView.setAdapter(adapter);
  }