嗨我想从扩展内容提供商的活动中获取光标 当我试图在主要活动中得到它 我需要给：
Cursor cursor = theprovider.query(Uri uri, String[] projection, String selection, String[] selectionArgs, String sortOrder);
我不明白在查询中要提供什么
这是主要活动：
public class MainActivity extends ActionBarActivity implements LoaderManager.LoaderCallbacks<Cursor> {
SimpleCursorAdapter adapter;
private TheProvider theprovider;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
theprovider = new TheProvider();
Cursor cursor = theprovider.query(Uri uri, String[] projection, String selection, String[] selectionArgs, String sortOrder);
startManagingCursor(cursor);
String [] from = {ConContract.PlacesCons.NAME,ConContract.PlacesCons.ADDRESS,
ConContract.PlacesCons.DISTANCE};
int[] to = {R.id.title_name,R.id.title_address,R.id.title_distance};
adapter = new SimpleCursorAdapter(this,R.layout.abc_list_menu_item_layout,cursor,
from,to,0);
ListView loc_list = (ListView) findViewById(R.id.Loc_list);
loc_list.setAdapter(adapter);
getLoaderManager().initLoader(1,null,null);
if (isInSingleFragment()) {
if (savedInstanceState == null) {
FragmentA fragmentA = new FragmentA();
FragmentManager fm = getFragmentManager();
FragmentTransaction ft = fm.beginTransaction();
ft.add(R.id.fragmnetContainer,fragmentA,"A");
ft.commit();
}
} else {
if (savedInstanceState == null) {
FragmentA fragmentA = new FragmentA();
FragmentB fragmentB = new FragmentB();
FragmentManager fm = getFragmentManager();
FragmentTransaction ft = fm.beginTransaction();
ft.add(R.id.fragmnetContainerA, fragmentA, "A");
ft.add(R.id.fragmnetContainerB, fragmentB, "B");
ft.commit();
}
}
}
private boolean isInSingleFragment() {
View layout = findViewById(R.id.layout_singleLayout);
if(layout!=null){
return true;
}
else{
return false;
}
}
@Override
public Loader<Cursor> onCreateLoader(int id, Bundle bundle) {
Uri uri = ConContract.PlacesCons.CONTENT_URI;
String[] projection = {
ConContract.PlacesCons.NAME,
ConContract.PlacesCons.ADDRESS,
ConContract.PlacesCons.DISTANCE
};
String selection = null;
String sortOrder = ConContract.PlacesCons.NAME + " desc" ;
return new CursorLoader(this,uri,projection,selection,null,sortOrder);
}
@Override
public void onLoadFinished(Loader<Cursor> loader, Cursor cursor) {
adapter.swapCursor(cursor);
}
@Override
public void onLoaderReset(Loader<Cursor> loader) {
adapter.swapCursor(null);
}
}