title: Where to place EventBus.getDefault().unregister in BaseAdapter
body: <p>Friends, I've spent enough time to find an answer to my question(here and on android's site) But no luck.
  Here is the logic:
   From DialogFragment upon finishing putting user's data he clicks OK button:</p>
  
  <pre><code>import de.greenrobot.event.EventBus;
  ...
  public class AddDialogFragment extends DialogFragment implements
          DialogInterface.OnClickListener {
  ...
   public void onClick(DialogInterface dialog, int which) {
  
          StringBuilder date = new StringBuilder(today.getText().subSequence(0,
                  today.getText().length()));
          date = (date.toString().equals(getString(R.string.today))) ? new StringBuilder("20150104") : date;
  
          int weight = 89;
          String[] bsi = rb.getSelectedItems();
          String[] gsi = rg.getSelectedItems();
  
          DatabaseManipulation dm = new DatabaseManipulation(getActivity());
          dm.run(date, weight, bsi, gsi);
          dm.destroy();
          DialogDataModel toSend = new DialogDataModel(weight, date.toString(), bsi, gsi);
  /*
          Context activity = getActivity();
          if (activity instanceof WDActivity)
              ((WDActivity) activity).updateListItemFragment();
  */
          EventBus.getDefault().post(new UpdateItemEvent(toSend));
          Log.d(LOG_TAG, "send event");
  
          Toast.makeText(getActivity(), R.string.saved_data, Toast.LENGTH_LONG).show();
  
      }
  ...
  </code></pre>
  
  <p>Event is successfully sent to Adapter class which is registered for receiving this event:</p>
  
  <pre><code>...
  import de.greenrobot.event.EventBus;    
  
  public class ItemsAdapter extends BaseAdapter implements ListAdapter {
      private static final  String LOG_TAG = "Logs";
  
      private ArrayList&lt;DialogDataModel&gt; list = new ArrayList&lt;DialogDataModel&gt;();
      private Context activity;
  
      public ItemsAdapter (ArrayList&lt;DialogDataModel&gt; list, Context context) {
          this.list = list;
          this.activity = context;
          registerEventBus();
      }
  
      @Override
      public int getCount() {
          return list.size();
      }
  
      @Override
      public Object getItem(int pos) {
          return list.get(pos);
      }
  
      @Override
      public long getItemId(int pos) {
          return pos;
          //just return 0 if your list items do not have an Id variable.
      }
  
      @Override
      public View getView(final int position, View convertView, ViewGroup parent) {
          View view = convertView;
          if (view == null) {
              LayoutInflater inflater = (LayoutInflater) activity.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
              view = inflater.inflate(R.layout.row_item, null);
          }
  
          DialogDataModel curData = list.get(position);
          TextView itemDate = (TextView)view.findViewById(R.id.item_date);
          itemDate.setText(curData.getDate());
  
          TextView itemWeight = (TextView)view.findViewById(R.id.item_weight);
          itemWeight.setText( Integer.toString(curData.getWeight()) );
  
          TextView itemEvents = (TextView)view.findViewById(R.id.item_events);
          itemEvents.setText(curData.getEventsShort());
  
          //Handle buttons and add onClickListeners
          ImageButton editBtn = (ImageButton)view.findViewById(R.id.item_edit_btn);
  
          editBtn.setOnClickListener(new View.OnClickListener() {
              @Override
              public void onClick(View v) {
                  if (activity instanceof WDActivity)
                      ((WDActivity) activity).AddNewData(v, list.get(position));
  
                  notifyDataSetChanged();
              }
          });
  
          ImageButton deleteBtn = (ImageButton) view.findViewById(R.id.item_delete_btn);
  
          deleteBtn.setOnClickListener(new View.OnClickListener() {
              @Override
              public void onClick(View v) {
                  String date = list.get(position).getDate();
  
                  DatabaseManipulation dm = new DatabaseManipulation(activity);
                  dm.deleteItem(date);
                  dm.destroy();
  
                  list.remove(position);
                  notifyDataSetChanged();
              }
          });
  
          return view;
      }
  
      public void registerEventBus(){
          if (!EventBus.getDefault().isRegistered(this)) EventBus.getDefault().register(this);
          Log.d(LOG_TAG, "Registred from adapter");
      }
  
      public void unregisterEventBus(){
          EventBus.getDefault().unregister(this);
      }
  
      public void onEventMainThread(UpdateItemEvent event) {
          Log.d(LOG_TAG, "Event fired!");
          list = DialogDataModel.replaceFieldsInArray(list,event.getModel());
          notifyDataSetChanged();
      }
  }
  </code></pre>
  
  <p>After clicking OK in dialog window the user sees the list of items and the item he's updated is up to date. Without this logic he sees the old version of this item item in the list and to refresh the list he needs to relaunch the app.</p>
  
  <p>Yes, it's working with EventBus.
  But as you can see here in the class there is no place for unregistering it from listening for UpdateItemEvent. Since there are no destructors in java(I don't believe that garbage collector should do this for me) I should handle this. Moreover the class registeres as listener in constructor (it happens several times, that's why you see this ugly if statement(<code>if (!EventBus.getDefault().isRegistered(this))</code>) You may ask me why not getting this adapter through Activity (there is the only one in the app) I tried building a chain <code>AddDialogFragment -&gt; WDActivity -&gt; PlaceholderFragment -&gt; ItemsAdapter</code></p>
  
  <pre><code>//AddDialogFragment 
     Context activity = getActivity();
     if (activity instanceof WDActivity)
        ((WDActivity) activity).updateListItemFragment();
  
  //WDActivity --beginTransaction().replace does not work here
    ...
    @Override
      protected void onCreate(Bundle savedInstanceState) {
          super.onCreate(savedInstanceState);
          setContentView(R.layout.activity_wd);
          Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
          setSupportActionBar(toolbar);
          // Create the adapter that will return a fragment for each of the three
          // primary sections of the activity.
          mSectionsPagerAdapter = new SectionsPagerAdapter(getSupportFragmentManager());
  
          // Set up the ViewPager with the sections adapter.
          mViewPager = (ViewPager) findViewById(R.id.container);
          mViewPager.setAdapter(mSectionsPagerAdapter);
  
      }
      ...
      public void updateListItemFragment() {
          android.support.v4.app.FragmentManager fragmentManager = getSupportFragmentManager();
          android.support.v4.app.Fragment currentFragment = fragmentManager.findFragmentById(R.id.container);
          if (currentFragment instanceof PlaceholderFragment &amp;&amp; currentFragment != null) {
              fragmentManager.beginTransaction().remove(currentFragment).commit();
              fragmentManager.beginTransaction().add(R.id.container, currentFragment).commit();
              ((PlaceholderFragment)currentFragment).fillList();
  
          }
  
  //PlaceholderFragment
    public class PlaceholderFragment extends Fragment {
      private static final  String LOG_TAG = "Logs";
  
      private static final String ARG_SECTION_NUMBER = "section_number";
  
      private ListView listViewItem;
  
      public static PlaceholderFragment newInstance(int sectionNumber) {
          PlaceholderFragment fragment = new PlaceholderFragment();
          Bundle args = new Bundle();
          args.putInt(ARG_SECTION_NUMBER, sectionNumber);
          fragment.setArguments(args);
          return fragment;
      }
      public PlaceholderFragment() {
      }
  
      @Override
      public View onCreateView(LayoutInflater inflater, ViewGroup container,
                               Bundle savedInstanceState) {
  
          if(getArguments().getInt(ARG_SECTION_NUMBER)==1)
              return onCreateViewInputChart(inflater, container, savedInstanceState);
          if(getArguments().getInt(ARG_SECTION_NUMBER)==2)
              return onCreateViewManual(inflater, container, savedInstanceState);
          return onCreateViewInputData(inflater, container, savedInstanceState);    
  
      }
  
      private View onCreateViewManual(LayoutInflater inflater, ViewGroup container,
                                      Bundle savedInstanceState) {
          View rootView = inflater.inflate(R.layout.fragment_howto, container, false);
          return rootView;
      }
  
      private View onCreateViewInputData(LayoutInflater inflater, ViewGroup container,
                                         Bundle savedInstanceState) {
          View rootView = inflater.inflate(R.layout.fragment_list_data, container, false);
  
          findViewsByIdListItem(rootView);
          fillList();
  
          return rootView;
      }
  
      private View onCreateViewInputChart(LayoutInflater inflater, ViewGroup container,
                                          Bundle savedInstanceState) {
          View rootView = inflater.inflate(R.layout.fragment_chart, container, false);
          return rootView;
      }
      //listViewItems
      private void findViewsByIdListItem(View v) {
          listViewItem = (ListView) v.findViewById(R.id.listViewItems);
      }
  
      public void fillList(){
          Context activity = getActivity();
          DatabaseManipulation dm = new DatabaseManipulation(activity);
          ArrayList&lt;DialogDataModel&gt; aldm = dm.getItemsList();
          dm.destroy();
  
          ItemsAdapter innerAdapter = new ItemsAdapter(aldm, activity);
  
          listViewItem.setAdapter(innerAdapter);
          ( (BaseAdapter) listViewItem.getAdapter() ).notifyDataSetChanged();
      }
  
      @Override
      public void onAttach(Context activity) {
          super.onAttach(activity);
      }
  
      @Override
      public void onDetach(){
          super.onDetach();
      }
    }
  
  //SectionsPagerAdapter - just for your information
    public class SectionsPagerAdapter extends FragmentPagerAdapter {
  
      public SectionsPagerAdapter(FragmentManager fm) {
          super(fm);
      }
  
      @Override
      public Fragment getItem(int position) {
          // getItem is called to instantiate the fragment for the given page.
          return PlaceholderFragment.newInstance(position);
      }
  
      @Override
      public int getCount() {
          return 3;
      }
  
      @Override
      public CharSequence getPageTitle(int position) {
          switch (position) {
              case 0:
                  return "Enter your data";
              case 1:
                  return "Chart";
              case 2:
                  return "How to use it";
          }
          return null;
      }
    }
  
  //ItemsAdapter is placed higher
  </code></pre>
  
  <p>This did not work. Finally I found out that the bottleneck is in linking PlaceholderFragment and ListAdapter: listViewItem is null everywhere except <code>onCreateViewInputData</code>. I could not figure out why. Google didn't give me the answer and I took it as a magic. Btw due to this feature I cannot use PlaceholderFragment's onAttach and onDetach for saying ItemsAdapter to register/unregister for receiving the event. This:</p>
  
  <pre><code>    @Override
      public void onAttach(Context activity) {
          super.onAttach(activity);
          ( (ItemsAdapter) listViewItem.getAdapter() ).registerEventBus();
      }
  </code></pre>
  
  <p>doesn't work for the same reason listViewItem is null. <strong>Maybe there is some way to manage with this more accurately?</strong> </p>