retofit2不调用onResponse或onFailure

Question

I make request in loadFriends() users names with method loadUserName() But nothing happens and second request ( loadUserName() ) triggered only for the first lane. I have logs and code of this fragment Also, AS tell me, that List "names" is never assigned , but do not I fill it in the method loadUserNames()? And is this related with my issue (not calling onResponse and onFailure ?) Other methods and requests work fine

public class FriendsFragment extends Fragment {

private String sid;
private PenyokService friendsService;
private RecyclerView friendsRecyclerView;
private FriendsAdapter friendsAdapter;
private List<Integer> ids;
private List<String> names;

public FriendsFragment() {
}

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {

    friendsRecyclerView = (RecyclerView) inflater.inflate(R.layout.fragment_stats, container, false);

    // view = getView();
    sid = ((MainActivity) getActivity()).getSid();
    friendsService = APIUtils.getPService();

    friendsRecyclerView = (RecyclerView) inflater.inflate(R.layout.fragment_stats, container, false);
    friendsAdapter = new FriendsAdapter(new ArrayList<Integer>(0), new ArrayList<String>(0), getActivity().getApplicationContext(), sid);
    friendsRecyclerView.setAdapter(friendsAdapter);
    LinearLayoutManager layoutManager = new LinearLayoutManager(getActivity());
    friendsRecyclerView.setLayoutManager(layoutManager);
    loadFriends();

    return friendsRecyclerView;
}

private void loadFriends(){
    friendsService.getFriends(sid).enqueue(new Callback<Model>() {

        @Override
        public void onResponse(Call<Model> call, Response<Model> response) {
            if(response.isSuccessful()) {
                ids = response.body().getMyFriends();
                Log.d("testtest", "start load names");
                for (int i : ids)
                    Log.d("test", "loaded names " + i);
                loadUserName(ids);
                Log.d("testtest", "loaded names");
                friendsAdapter.updateFriends(response.body().getMyFriends(), names);
                // Toast.makeText(getActivity(), "Gav gav", Toast.LENGTH_SHORT).show();
            }
        }

        @Override
        public void onFailure(Call<Model> call, Throwable t) {
            //showErrorMessage();
            Log.d("testtest", t.toString());
            Toast.makeText(getActivity(), t.toString(), Toast.LENGTH_SHORT).show();
        }
    });
}

private void loadUserName(List<Integer> id) {
    Log.d("test", "loading names");
    for (int x : id) {
        Log.d("testtest", "after for " + x);
        friendsService.getUserName(x, sid).enqueue(new Callback<Model>() {

            @Override
            public void onResponse(Call<Model> call, Response<Model> response) {
                Log.d("testtest", "before response is successful");
                if (response.isSuccessful()) {
                    Log.d("testtest", "response is successful");
                    if (response.body().getNameFor() != null) {
                        names.add(response.body().getNameFor());
                        Log.d("testtest", "in onResponse");
                    }
                else {
                        names.add("Set your name");
                        Log.d("testtest", "we set name");
                    }
                }
            }

            @Override
            public void onFailure(Call<Model> call, Throwable t) {
                //showErrorMessage();
                Log.d("testtest", t.toString() + "loadUserName");
                // Toast.makeText(getActivity(), t.toString(), Toast.LENGTH_SHORT).show();
            }
        });
    }
}

}

09-07 15:35:30.993 6238-6238/com.journaldev.navigationdrawer D/testtest: start load names
09-07 15:35:30.993 6238-6238/com.journaldev.navigationdrawer D/test: loaded names 1
09-07 15:35:30.993 6238-6238/com.journaldev.navigationdrawer D/test: loaded names 2
09-07 15:35:30.993 6238-6238/com.journaldev.navigationdrawer D/test: loaded names 4
09-07 15:35:30.993 6238-6238/com.journaldev.navigationdrawer D/test: loading names
09-07 15:35:30.993 6238-6238/com.journaldev.navigationdrawer D/testtest: after for 1
09-07 15:35:31.053 6238-6238/com.journaldev.navigationdrawer D/testtest: after for 2
09-07 15:35:31.063 6238-6238/com.journaldev.navigationdrawer D/testtest: after for 4
09-07 15:35:31.103 6238-6238/com.journaldev.navigationdrawer D/testtest: loaded names

Answer 1

Code after retrofit requests is starting very quickly. It starts faster than the response from the server comes Solution - think about the structure of calling methods (get full response --> start next method)

Answer 2

我们从未创建过names变量，我们没有创建列表的实例。如果您尝试向列表中添加任何当前为null的内容，则会导致NullPointerException 。我建议将列表初始化为

private List<String> names=new ArrayList<>();