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Всем привет..Я поражен здесь, я должен отображать новости в отдельном виде списка с веб-сайта со ссылкой на новости, но при отладке курсор становится нулевым. Как мне это решить? Вот мой код

 package adn.GoMizzou.NB;

import java.io.IOException;
import java.io.UnsupportedEncodingException;
import java.net.URI;
import java.net.URISyntaxException;

import javax.xml.parsers.ParserConfigurationException;
import javax.xml.parsers.SAXParser;
import javax.xml.parsers.SAXParserFactory;

import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.entity.BufferedHttpEntity;
import org.apache.http.entity.StringEntity;
import org.apache.http.impl.client.DefaultHttpClient;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;
import org.xml.sax.XMLReader;

import android.app.ListActivity;
import android.app.ProgressDialog;
import android.content.Context;
import android.content.Intent;
import android.content.SharedPreferences;
import android.database.Cursor;
import android.net.Uri;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.view.View;
import android.widget.ListView;
import android.widget.SimpleCursorAdapter;
import android.widget.TextView;
import android.widget.Toast;



public class NB extends ListActivity {
    public static final String URL = "http://nbsubscribe.missouri.edu/news-releases/feed/atom/";

    private String msg;
    private boolean success;
    private int scrollIndex;
    private int scrollTop;
    private HttpClient httpClient;
    private NBDBAdapter dbAdapter;
    private ProgressDialog pDialog;
    private Context ctx = this;
    private SharedPreferences prefs;
    private SharedPreferences.Editor prefsEditor;
    //private Cursor cur;
    private Cursor q;

    private Handler handler = new Handler() {
        @Override
        public void handleMessage(Message msg){
            pDialog.dismiss();
            fillList();
        }
    };

    /*  ACTIVITY METHODS    */
    @Override
    public void onCreate(Bundle savedInstanceState){
        super.onCreate(savedInstanceState);
        setContentView(R.layout.nb);
        setTitle("News");
        q=null;
        scrollIndex = 0;
        dbAdapter = new NBDBAdapter(this);
        dbAdapter.open();

        registerForContextMenu(getListView());

        getData();
    }

    public void getData(){
        pDialog = ProgressDialog.show(this, "", "Loading. Please wait...", true);
        new Thread(){
            public void run(){
                dbAdapter.deleteAll();
                dbAdapter.close();

                doPost(URL, "");

                dbAdapter.open();
                handler.sendEmptyMessage(0);
            }
        }.start();
    }

    public boolean doPost(String url, String postMsg){
        HttpResponse response = null;

        createHttpClient();
        try {
            URI uri = new URI(url);
            HttpPost httppost = new HttpPost(uri);
            StringEntity postEntity = new StringEntity(postMsg);
            httppost.setHeader("Content-Type", "application/x-www-form-urlencoded");
            postEntity.setContentType("application/x-www-form-urlencoded");
            httppost.setEntity(postEntity);
            response = httpClient.execute(httppost);
        } catch (UnsupportedEncodingException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (ClientProtocolException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        } catch (URISyntaxException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }

        if(response == null){
            msg = "No internet connection.";
            return false;
        }

        if(response.getStatusLine().getStatusCode()!= 200){
            msg = "Server error.";
            return false;
        }

        return doParse(response);
    }

    public void createHttpClient(){
        if(httpClient == null){
            httpClient = new DefaultHttpClient();
        }
    }

    public boolean doParse(HttpResponse response){
        try {
            SAXParserFactory spf = SAXParserFactory.newInstance();
            SAXParser sp = spf.newSAXParser();
            XMLReader xr = sp.getXMLReader();

            NBParser respHandler = new NBParser(ctx);
            xr.setContentHandler(respHandler);

            HttpEntity entity = response.getEntity();
            BufferedHttpEntity buffEntity = new BufferedHttpEntity(entity);

            xr.parse(new InputSource(buffEntity.getContent()));
        } catch (ParserConfigurationException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (SAXException e) {
            e.printStackTrace();
            if(e.getMessage().toString().contains("nothing found")){
                msg = e.getMessage().toString();
                return false;
            }
        } catch (IOException e) {
            e.printStackTrace();
        }

        return true;
    }
    protected void onListItemClick(ListView l, View v, int position, long id) {
        super.onListItemClick(l, v, position, id);
         Cursor c = q;
        q.moveToPosition(position);
        //Intent i = new Intent(this, NB.class);
        //i.putExtra("link",  c.getString(c.getColumnIndexOrThrow(NBDBAdapter.NB_LINK)));
        String newsLinkString = q.getString(q.getColumnIndexOrThrow(NBDBAdapter.NB_LINK));

        TextView linkTV = (TextView) v.findViewById(R.id.rowlink);
        newsLinkString = linkTV.getText().toString();

        if (newsLinkString.startsWith("http://")){
            Uri uri = Uri.parse(newsLinkString);
            Intent i = new Intent(this, NB.class);
            //  Save ListView position 
           i.putExtra("link",  c.getString(c.getColumnIndexOrThrow(NBDBAdapter.NB_LINK)));

            startActivity(i);
        }
    }       

        //else {
            //showLinkError();
       //}
//      Sends an error message to the user if the news item link is malformed
        //public void showLinkError() {
            //Toast.makeText(getApplicationContext(), "Error - Link to story unavailable with news source could not load the News Story", Toast.LENGTH_SHORT).show();
        //}


    private void showLinkError() {
        // TODO Auto-generated method stub
        Toast.makeText(getApplicationContext(), "Error - Link to story unavailable with news source could not load the News Story", Toast.LENGTH_SHORT).show();

    }

    public void fillList(){
        if(!success) {
            TextView emptyView = (TextView) findViewById(android.R.id.empty);
            emptyView.setText(msg);
            msg = "";
        }
        if(!dbAdapter.isOpen()) dbAdapter.open();
        Cursor cursor = dbAdapter.fetchAll();
        startManagingCursor(cursor);

        String [] from = new String[] { dbAdapter.NB_AUTHOR, dbAdapter.NB_TITLE,dbAdapter.NB_LINK };
        int[] to = new int[] { R.id.rowAuthor, R.id.rowTitle, R.id.rowlink };

        SimpleCursorAdapter list = new SimpleCursorAdapter(this, R.layout.row, cursor, from, to);
        setListAdapter(list);
    }


}
  

О каком курсоре вы говорите?

Если это происходит при нажатии на элемент, это потому, что вы присваиваете курсору q null в onCreate, а затем вызываете moveToPosition для него в onListItemClick.