SimpleCursorTreeAdapter and CursorLoader for ExpandableListView

So i figured out that I needed to map loaderids to groupPositions and this solved my issue:

Here is my Fragment class which implements the CursorLoader

public class GroupsListFragment extends ExpandableListFragment implements
  LoaderManager.LoaderCallbacks<Cursor> {

  private final String DEBUG_TAG = getClass().getSimpleName().toString();      

  private static final String[] CONTACTS_PROJECTION = new String[] {
    ContactsContract.Contacts._ID,
    ContactsContract.Contacts.DISPLAY_NAME };  

  private static final String[] GROUPS_PROJECTION = new String[] {
    ContactsContract.Groups.TITLE, ContactsContract.Groups._ID };

  GroupsAdapter mAdapter;

  @Override
  public void onActivityCreated(Bundle savedInstanceState) {
    super.onActivityCreated(savedInstanceState);

    populateContactList();

    // Prepare the loader. Either re-connect with an existing one,
    // or start a new one.
    Loader loader = getLoaderManager().getLoader(-1);
    if (loader != null && !loader.isReset()) {
      getLoaderManager().restartLoader(-1, null, this);
    } else {
      getLoaderManager().initLoader(-1, null, this);
    }
  } 

  public Loader<Cursor> onCreateLoader(int id, Bundle args) {
    // This is called when a new Loader needs to be created.
    Log.d(DEBUG_TAG, "onCreateLoader for loader_id " + id);
    CursorLoader cl;
    if (id != -1) {
      // child cursor
      Uri contactsUri = ContactsContract.Data.CONTENT_URI;
      String selection = "((" + ContactsContract.Contacts.DISPLAY_NAME
        + " NOTNULL) AND ("
        + ContactsContract.Contacts.HAS_PHONE_NUMBER + "=1) AND ("
        + ContactsContract.Contacts.DISPLAY_NAME + " != '') AND ("
        + ContactsContract.CommonDataKinds.GroupMembership.GROUP_ROW_ID
        + " = ? ))";
      String sortOrder = ContactsContract.Contacts.DISPLAY_NAME
        + " COLLATE LOCALIZED ASC";
      String[] selectionArgs = new String[] { String.valueOf(id) };

      cl = new CursorLoader(getActivity(), contactsUri,
        CONTACTS_PROJECTION, selection, selectionArgs, sortOrder);
    } else {
      // group cursor
      Uri groupsUri = ContactsContract.Groups.CONTENT_URI;
      String selection = "((" + ContactsContract.Groups.TITLE
        + " NOTNULL) AND (" + ContactsContract.Groups.TITLE
        + " != '' ))";
      String sortOrder = ContactsContract.Groups.TITLE
        + " COLLATE LOCALIZED ASC";
      cl = new CursorLoader(getActivity(), groupsUri,
        GROUPS_PROJECTION, selection, null, sortOrder);
    }

    return cl;
  }

  public void onLoadFinished(Loader<Cursor> loader, Cursor data) {
    // Swap the new cursor in. 
    int id = loader.getId();
    Log.d(DEBUG_TAG, "onLoadFinished() for loader_id " + id);
    if (id != -1) {
      // child cursor
      if (!data.isClosed()) {
        Log.d(DEBUG_TAG, "data.getCount() " + data.getCount());

        HashMap<Integer,Integer> groupMap = mAdapter.getGroupMap();
        try {
          int groupPos = groupMap.get(id);
          Log.d(DEBUG_TAG, "onLoadFinished() for groupPos " + groupPos);
          mAdapter.setChildrenCursor(groupPos, data);
        } catch (NullPointerException e) {
          Log.w("DEBUG","Adapter expired, try again on the next query: "
            + e.getMessage());
        }
      }
    } else {
      mAdapter.setGroupCursor(data);
    }

  }

  public void onLoaderReset(Loader<Cursor> loader) {
    // This is called when the last Cursor provided to onLoadFinished()
    // is about to be closed.
    int id = loader.getId();
    Log.d(DEBUG_TAG, "onLoaderReset() for loader_id " + id);
    if (id != -1) {
      // child cursor
      try {
        mAdapter.setChildrenCursor(id, null);
      } catch (NullPointerException e) {
        Log.w("TAG", "Adapter expired, try again on the next query: "
          + e.getMessage());
      }
    } else {
      mAdapter.setGroupCursor(null);
    }
  }

  /**
  * Populate the contact list
  */
  private void populateContactList() {
    // Set up our adapter
    mAdapter = new GroupsAdapter(getActivity(),this,
      android.R.layout.simple_expandable_list_item_1,
      android.R.layout.simple_expandable_list_item_1,
      new String[] { ContactsContract.Groups.TITLE }, // Name for group layouts
      new int[] { android.R.id.text1 },
      new String[] { ContactsContract.Contacts.DISPLAY_NAME }, // Name for child layouts
      new int[] { android.R.id.text1 });

    setListAdapter(mAdapter);
  }
}

And here is my adapter which subclasses SimpleCursorTreeAdapter

public class GroupsAdapter extends SimpleCursorTreeAdapter {

  private final String DEBUG_TAG = getClass().getSimpleName().toString();

  private ContactManager mActivity;
  private GroupsListFragment mFragment;

  protected final HashMap<Integer, Integer> mGroupMap;

  // Note that the constructor does not take a Cursor. This is done to avoid
  // querying the database on the main thread.
  public GroupsAdapter(Context context, GroupsListFragment glf,
    int groupLayout, int childLayout, String[] groupFrom,
    int[] groupTo, String[] childrenFrom, int[] childrenTo) {

    super(context, null, groupLayout, groupFrom, groupTo, childLayout,
      childrenFrom, childrenTo);
    mActivity = (ContactManager) context;
    mFragment = glf;
    mGroupMap = new HashMap<Integer, Integer>();
  }

  @Override
  protected Cursor getChildrenCursor(Cursor groupCursor) {
    // Given the group, we return a cursor for all the children within that group
    int groupPos = groupCursor.getPosition();
    int groupId = groupCursor.getInt(groupCursor
      .getColumnIndex(ContactsContract.Groups._ID));
    Log.d(DEBUG_TAG, "getChildrenCursor() for groupPos " + groupPos);
    Log.d(DEBUG_TAG, "getChildrenCursor() for groupId " + groupId);

    mGroupMap.put(groupId, groupPos);

    Loader loader = mActivity.getLoaderManager().getLoader(groupId); 
    if ( loader != null && !loader.isReset() ) { 
      mActivity.getLoaderManager().restartLoader(groupId, null, mFragment); 
    } else { 
      mActivity.getLoaderManager().initLoader(groupId, null, mFragment); 
    } 

    return null;    
  }

  //Accessor method
  public HashMap<Integer, Integer> getGroupMap() {
    return mGroupMap;
  }

}

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