package org.mercury_im.messenger.ui.roster; import android.content.Context; import android.os.Bundle; import android.util.Log; import android.view.LayoutInflater; import android.view.View; import android.view.ViewGroup; import androidx.fragment.app.Fragment; import androidx.lifecycle.ViewModelProviders; import androidx.recyclerview.widget.RecyclerView; import org.mercury_im.messenger.R; import java.util.ArrayList; import static androidx.constraintlayout.widget.Constraints.TAG; /** * A placeholder fragment containing a simple view. */ public class RosterFragment extends Fragment { private RosterViewModel rosterViewModel; private RosterRecyclerViewAdapter recyclerViewAdapter; RecyclerView recyclerView; public RosterFragment() { } @Override public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) { View view = inflater.inflate(R.layout.fragment_roster_entry_list, container, false); recyclerView = view.findViewById(R.id.roster_entry_list__recycler_view); recyclerViewAdapter = new RosterRecyclerViewAdapter(new ArrayList<>()); recyclerView.setAdapter(recyclerViewAdapter); return view; } @Override public void onAttach(Context context) { super.onAttach(context); rosterViewModel = ViewModelProviders.of(getActivity()).get(RosterViewModel.class); observeViewModel(rosterViewModel); } private void observeViewModel(RosterViewModel viewModel) { viewModel.getRosterEntryList().observe(this, rosterEntries -> { if (rosterEntries == null) { Log.d(TAG, "Displaying null roster entries"); return; } recyclerViewAdapter.setItems(rosterEntries); Log.d(TAG, "Displaying " + rosterEntries.size() + " roster entries"); }); } }