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我正在實現一個ListActivity和ListFragment，並希望允許用戶使用短點擊和長點擊 - 短暫編輯/顯示該項目的詳細信息，然後長按以彈出一個上下文菜單並帶有刪除選項該項目。但是，我似乎無法觸發onCreateContextMenu。 onListItemClick工作正常，並捕獲所有的水龍頭，無論短期還是長期。 ListFragment使用稍微自定義的SimpleCursorAdaptor和LoaderManager來填充，而不是使用佈局文件。Android ListFragment：如何讓onListItemClick和onContextItemSelected？
是可能有兩個？
代碼...
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);
}
}
更新：我還沒有想通了這一點，我想知道，如果我不得不放棄這一策略，並在其他一些實現它，而不是用戶友好的方式。也許滑動查看細節和點擊刪除？