Fragment code:
public class ResultsFragment extends Fragment { private String id; private RecyclerView recyclerView; @Override public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) { View view = inflater.inflate(R.layout.fragment_results, container, false); ActivityFragments activityFragments = (ActivityFragments) getActivity(); id = activityFragments.getMyData(); // AllResultPresenter allResultPresenter = new AllResultPresenter(id,ResultsFragment.this); return view; } @Override public void onViewCreated(View view, @Nullable Bundle savedInstanceState) { // super.onViewCreated(view, savedInstanceState); recyclerView = (RecyclerView) view.findViewById(R.id.recycler_view_all); recyclerView.setHasFixedSize(true); final LinearLayoutManager linearLayoutManager = new LinearLayoutManager(getActivity()); recyclerView.setLayoutManager(linearLayoutManager); AllResultPresenter allResultPresenter = new AllResultPresenter(id,ResultsFragment.this); } public void showAllResult(ArrayList<Result> allResultResponses) { recyclerView.setAdapter(new AllResultsAdapter(this, allResultResponses)); } } And here is the Presenter code:
public class AllResultPresenter { private ResultsFragment resultsFragment; private ArrayList<Result> results; private String id; public AllResultPresenter(String mId, final ResultsFragment mResultsFragment) { this.id = mId; this.resultsFragment = mResultsFragment; results = new ArrayList<>(); Retrofit retrofit = new Retrofit.Builder() .baseUrl("https://asthmacare.ru/") .addConverterFactory(GsonConverterFactory.create()) .build(); retrofit.create(API.class).getAllResultResponse(id).enqueue(new Callback<AllResultResponse>() { @Override public void onResponse(Call<AllResultResponse> call, Response<AllResultResponse> response) { //ArrayList<allRes> = response.body().getResults(); results = response.body().getResults(); resultsFragment.showAllResult(results); } @Override public void onFailure(Call<AllResultResponse> call, Throwable t) { } }); } } For some reason the error takes off:
java.lang.NullPointerException: Attempt to invoke virtual method 'void android.support.v7.widget.RecyclerView.setHasFixedSize (boolean)' on a null object reference
