Android ListFragment: how to have both onListItemClick and onContextItemSelected?

android, android-listfragment, contextmenu

Solution

I've found my answer in the Android source code for the native Email app. https://android.googlesource.com/platform/packages/apps/Email/

The ListFragment must implement listeners:

public class MessageListFragment extends SherlockListFragment
    implements LoaderManager.LoaderCallbacks<Cursor>, AdapterView.OnItemLongClickListener

    private static final int DELETE_ID = Menu.FIRST + 1;    

    private SimpleCursorAdapter adapter;

    // The LoaderManager needs initializing
    @Override
    public void onCreate(Bundle savedInstanceState) {

       super.onCreate(savedInstanceState);

       // Fields from the database (projection)
       // Must include the _id column for the adapter to work
       String[] from = new String[] { BookmarksTable.BOOKMARK_NAME, 
            BookmarksTable.BOOKMARK_PHONE_NAME };
       // Fields on the UI to which we map
       int[] to = new int[] { R.id.titleText, R.id.phoneText };

       // connect to the database
       getLoaderManager().initLoader(0, null, this);
       adapter = new BookmarkCursorAdapter(getActivity(), 
            R.layout.bookmark_row, null, from, to, 0);

       setListAdapter(adapter);
    }

    // register to put up the context menu
    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
        Bundle savedInstanceState) {
       View root = super.onCreateView(inflater, container, savedInstanceState); 
       registerForContextMenu(root);
       return root;
    }

    // set the listeners for long click
    @Override
    public void onViewCreated(View view, Bundle savedInstanceState) {
        super.onViewCreated(view, savedInstanceState);
        getListView().setChoiceMode(ListView.CHOICE_MODE_SINGLE);
        getListView().setOnItemLongClickListener(this);
    }

The called methods are:

 /**
  * Called when a message is clicked.
  */
 @Override
 public void onListItemClick(ListView parent, View view, int position, long id) {
        // do item click stuff; show detailed view in my case

 }


@Override
public boolean onItemLongClick(AdapterView<?> parent, View view, int position, long id) {
    return false; // let the system show the context menu
  }

// Context menu
@Override
public void onCreateContextMenu(ContextMenu menu, View v,
        ContextMenuInfo menuInfo) {
    super.onCreateContextMenu(menu, v, menuInfo);
    menu.add(0, DELETE_ID, 0, R.string.menu_delete);
}

    // respond to the context menu tap
@Override
public boolean onContextItemSelected(android.view.MenuItem item) {
    switch (item.getItemId()) {
    case DELETE_ID:
        AdapterContextMenuInfo info = (AdapterContextMenuInfo) item
                .getMenuInfo();
        Uri uri = Uri.parse(DatabaseContentProvider.BOOKMARK_ID_URI + Long.toString(info.id));
        getActivity().getContentResolver().delete(uri, null, null);
        return true;
    }
    return super.onContextItemSelected(item);
}

For completeness, here's the loader code

// Loader code
// Creates a new loader after the initLoader () call
@Override
public Loader<Cursor> onCreateLoader(int id, Bundle args) {
    String[] projection = { BookmarksTable.KEY_ID, BookmarksTable.BOOKMARK_NAME, BookmarksTable.BOOKMARK_PHONE_NAME };
    CursorLoader cursorLoader = new CursorLoader(getActivity(),
            DatabaseContentProvider.BOOKMARKS_URI, projection, null, null, null);
    return cursorLoader;
}

@Override
public void onLoadFinished(Loader<Cursor> loader, Cursor data) {
    adapter.swapCursor(data);
}

@Override
public void onLoaderReset(Loader<Cursor> loader) {
    // data is not available anymore, delete reference
    adapter.swapCursor(null);
}

Problem

I'm implementing a ListActivity and ListFragment and would like to allow the user to use short taps and long taps - short being to edit/show the details of the item and long tap to bring up a context menu with the option to delete the item. I don't seem to be able to trigger the onCreateContextMenu, however. onListItemClick works fine and captures all taps, short or long. The ListFragment is populated using a slightly custom SimpleCursorAdaptor and LoaderManager, not using a layout file. Is is possible to have both? Code... ``` LocationsListFragment.java package com.level3.connect.locations; //import removed for brevity public class LocationsListFragment extends SherlockListFragment implements LoaderManager.LoaderCallbacks<Cursor>{ private static final int DELETE_ID = Menu.FIRST + 1; private SimpleCursorAdapter adapter; private OnLocationSelectedListener locationSelectedListener; // the activity attaching to this fragment should implement this interface public interface OnLocationSelectedListener { public void onLocationSelected(String locationId); } @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); // Fields from the database (projection) // Must include the _id column for the adapter to work String[] from = new String[] { LocationsTable.LOCATION_NAME, LocationsTable.LOCATION_PHONE_NAME }; // Fields on the UI to which we map int[] to = new int[] { R.id.titleText, R.id.phoneText }; // connect to the database getLoaderManager().initLoader(0, null, this); adapter = new LocationCursorAdapter(getActivity(), R.layout.location_row, null, from, to, 0); setListAdapter(adapter); } @Override public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) { View root = super.onCreateView(inflater, container, savedInstanceState); registerForContextMenu(root); //this is called fine return root; } // hook up listening for the user selecting a location in the list @Override public void onAttach(Activity activity) { super.onAttach(activity); try { locationSelectedListener = (OnLocationSelectedListener) activity; } catch (ClassCastException e) { throw new ClassCastException(activity.toString() + " must implement OnLocationSelectedListener"); } } // handle user tapping a location - show a detailed view - this works fine @Override public void onListItemClick(ListView l, View v, int position, long id) { String projection[] = { LocationsTable.KEY_ID }; Cursor locationCursor = getActivity().getContentResolver().query( Uri.withAppendedPath(DatabaseContentProvider.CONTENT_URI, String.valueOf(id)), projection, null, null, null); if (locationCursor.moveToFirst()) { String locationUrl = locationCursor.getString(0); locationSelectedListener.onLocationSelected(locationUrl); } locationCursor.close(); } // Context menu - this is never called @Override public void onCreateContextMenu(ContextMenu menu, View v, ContextMenuInfo menuInfo) { super.onCreateContextMenu(menu, v, menuInfo); menu.add(0, DELETE_ID, 0, R.string.menu_delete); } @Override - this is never called public boolean onContextItemSelected(android.view.MenuItem item) { switch (item.getItemId()) { case DELETE_ID: AdapterContextMenuInfo info = (AdapterContextMenuInfo) item .getMenuInfo(); Uri uri = Uri.parse(DatabaseContentProvider.CONTENT_URI + "/" + info.id); getActivity().getContentResolver().delete(uri, null, null); return true; } return super.onContextItemSelected(item); } // Loader code // Creates a new loader after the initLoader () call @Override public Loader<Cursor> onCreateLoader(int id, Bundle args) { String[] projection = { LocationsTable.KEY_ID, LocationsTable.LOCATION_NAME, LocationsTable.LOCATION_PHONE_NAME }; CursorLoader cursorLoader = new CursorLoader(getActivity(), DatabaseContentProvider.CONTENT_URI, projection, null, null, null); return cursorLoader; } @Override public void onLoadFinished(Loader<Cursor> loader, Cursor data) { adapter.swapCursor(data); } @Override public void onLoaderReset(Loader<Cursor> loader) { // data is not available anymore, delete reference adapter.swapCursor(null); } } ``` UPDATE: I still have not figured this out and am wondering if I have to abandon this strategy and implement it in some other, not as user-friendly manner. Perhaps a swipe to view details and a tap to delete?

Original source