title: Fragment not attached to a context
body: <p>In activity in Toolbar I got a button which need to call method from fragment and update list in that fragment. Now it is an error.
  Calling in activity</p>
  
  <pre><code>@Override
  public boolean onOptionsItemSelected(MenuItem item) {
      switch (item.getItemId()){
          case  R.id.menu_sort:
              ListFragment listFragment = new ListFragment();
              listFragment.sortByPopularity();
              break;
      }
      return super.onOptionsItemSelected(item);
  }
  </code></pre>
  
  <p>Fragment code. I have found an error when Activity not attached. But nothing with context</p>
  
  <pre><code>public class ListFragment extends Fragment implements ListAdapter.ItemClickListener {
  
      /**
       * Needed
       */
      RecyclerView recyclerView;
      View view;
      List&lt;BasePojo.Result&gt; list;
      ListAdapter listAdapter;
  
      public ListFragment() {
      }
  
      @Override
      public View onCreateView(LayoutInflater inflater, ViewGroup container,
                               Bundle savedInstanceState) {
  
          /**
           * Main Initialization
           */
          view = inflater.inflate(R.layout.fragment_list, container, false);
          recyclerView = view.findViewById(R.id.recycler_list_detailed);
          recyclerView.setLayoutManager(new GridLayoutManager(getActivity(), 2));
          list = new ArrayList&lt;&gt;();
          listAdapter = new ListAdapter(list, setOnItemClickCallback());
          recyclerView.setAdapter(listAdapter);
  
          RetrofitClient.getApiService().getPhotosList(getString(R.string.api_key)).enqueue(new Callback&lt;BasePojo&gt;() {
              @Override
              public void onResponse(Call&lt;BasePojo&gt; call, Response&lt;BasePojo&gt; response) {
                  BasePojo basePojo = response.body();
                  list.addAll(basePojo.getResults());
                  recyclerView.getAdapter().notifyDataSetChanged();
              }
  
              @Override
              public void onFailure(Call&lt;BasePojo&gt; call, Throwable t) {
                  Log.d("tag", "Response failed" + t.toString());
  
              }
          });
  
  
          return view;
      }
  
      @Override
      public void onItemClick(View view, int position) {
          Log.v("in on click", "value " + position);
  
      }
  
      private OnItemClickListener.OnItemClickCallback setOnItemClickCallback() {
          OnItemClickListener.OnItemClickCallback onItemClickCallback = new OnItemClickListener.OnItemClickCallback() {
              @Override
              public void onItemClicked(View view, int position) {
                  BasePojo.Result itemClicked = list.get(position);
                  Bundle bundle = new Bundle();
                  bundle.putString("title", itemClicked.getOriginalTitle());
                  bundle.putString("overview", itemClicked.getOverview());
                  bundle.putString("release_date", itemClicked.getReleaseDate());
                  bundle.putString("vote_average", itemClicked.getVoteAverage().toString());
                  bundle.putString("poster_path", itemClicked.getPosterPath());
                  DetailedFragment detailedFragment = new DetailedFragment();
                  detailedFragment.setArguments(bundle);
                  FragmentManager manager = getActivity().getSupportFragmentManager();
                  FragmentTransaction transaction = manager.beginTransaction();
                  transaction.replace(R.id.main_frame_list, detailedFragment);
                  Log.d("tag", "title is 111 " + bundle.get("title"));
  
                  transaction.commit();
              }
  
          };
          return onItemClickCallback;
      }
  
      @Override
      public void onAttachFragment(Fragment childFragment) {
          super.onAttachFragment(childFragment);
  
      }
  
      public void sortByPopularity() {
          RetrofitClient.getApiService().getPopularList(getString(R.string.api_key)).enqueue(new Callback&lt;BasePojo&gt;() {
              @Override
              public void onResponse(Call&lt;BasePojo&gt; call, Response&lt;BasePojo&gt; response) {
                  BasePojo basePojo = response.body();
                  list.addAll(basePojo.getResults());
                  recyclerView.getAdapter().notifyDataSetChanged();
              }
  
              @Override
              public void onFailure(Call&lt;BasePojo&gt; call, Throwable t) {
                  Log.d("tag", "Response failed" + t.toString());
  
              }
          }); }
  
  }
  </code></pre>
  
  <p>And here is an error</p>
  
  <pre><code>05-09 12:48:26.915 5775-5775/com.borisruzanov.popularmovies E/AndroidRuntime: FATAL EXCEPTION: main
  Process: com.borisruzanov.popularmovies, PID: 5775
  java.lang.IllegalStateException: Fragment ListFragment{6dbd6de} not attached to a context.
      at android.support.v4.app.Fragment.requireContext(Fragment.java:614)
      at android.support.v4.app.Fragment.getResources(Fragment.java:678)
      at android.support.v4.app.Fragment.getString(Fragment.java:700)
      at com.borisruzanov.popularmovies.ListFragment.sortByPopularity(ListFragment.java:110)
      at com.borisruzanov.popularmovies.MainActivity.onOptionsItemSelected(MainActivity.java:47)
      at android.app.Activity.onMenuItemSelected(Activity.java:3204)
      at android.support.v4.app.FragmentActivity.onMenuItemSelected(FragmentActivity.java:407)
      at android.support.v7.app.AppCompatActivity.onMenuItemSelected(AppCompatActivity.java:195)
      at android.support.v7.view.WindowCallbackWrapper.onMenuItemSelected(WindowCallbackWrapper.java:108)
      at android.support.v7.view.WindowCallbackWrapper.onMenuItemSelected(WindowCallbackWrapper.java:108)
      at android.support.v7.app.ToolbarActionBar$2.onMenuItemClick(ToolbarActionBar.java:63)
      at android.support.v7.widget.Toolbar$1.onMenuItemClick(Toolbar.java:203)
      at android.support.v7.widget.ActionMenuView$MenuBuilderCallback.onMenuItemSelected(ActionMenuView.java:780)
      at android.support.v7.view.menu.MenuBuilder.dispatchMenuItemSelected(MenuBuilder.java:822)
      at android.support.v7.view.menu.MenuItemImpl.invoke(MenuItemImpl.java:171)
      at android.support.v7.view.menu.MenuBuilder.performItemAction(MenuBuilder.java:973)
      at android.support.v7.view.menu.MenuBuilder.performItemAction(MenuBuilder.java:963)
      at android.support.v7.widget.ActionMenuView.invokeItem(ActionMenuView.java:624)
      at android.support.v7.view.menu.ActionMenuItemView.onClick(ActionMenuItemView.java:150)
      at android.view.View.performClick(View.java:5610)
      at android.view.View$PerformClick.run(View.java:22265)
      at android.os.Handler.handleCallback(Handler.java:751)
      at android.os.Handler.dispatchMessage(Handler.java:95)
      at android.os.Looper.loop(Looper.java:154)
      at android.app.ActivityThread.main(ActivityThread.java:6077)
      at java.lang.reflect.Method.invoke(Native Method)
      at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:866)
      at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:756)
  </code></pre>
  
  <p>Thank you very much for your time and help. If my question looks not well please make a note and I will teach how to ask questions better</p>