Android: notifyDataSetChanged heißt aber Listenansicht nicht aktualisiert

Habe ich diese ListView, die ist bevölkert von einem JSON-Daten im web. Aber wenn ich aktualisiert, die JSON-Eintrag ein, beispielsweise das hinzufügen eines neuen Eintrags der ListView nicht mehr aktualisiert. Es zeigt nicht den neuen Eintrag auf der Liste obwohl ich bereits genannt, die notifyDataSetChanged().

Kann jemand mir helfen? Danke.

Hier ist mein code:

public class ProjectsList extends Activity {
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.projects_list);
        Intent serviceIntent = new Intent(this, LooserSync.class);
        startService(serviceIntent);
        ListView listView = (ListView) findViewById(R.id.lstText);
        MySimpleCursorAdapter projectAdapter = new MySimpleCursorAdapter(this, R.layout.listitems,
                managedQuery(Uri.withAppendedPath(LooserProvider.CONTENT_URI,
                        Database.Project.NAME), new String[] { BaseColumns._ID,
                        Database.Project.C_PROJECTTITLE, Database.Project.C_SMALLIMAGE }, null, null,
                        null), new String[] { Database.Project.C_PROJECTTITLE, Database.Project.C_SMALLIMAGE }, new int[] {
                        R.id.txt_title, R.id.image });
        listView.setAdapter(projectAdapter);
        projectAdapter.notifyDataSetChanged();


        listView.setOnItemClickListener(new OnItemClickListener() {
            public void onItemClick(AdapterView<?> parent, View view, int position, long id) {              

                Intent i = new Intent(ProjectsList.this, DetailsActivity.class);
                i.setData(Uri.withAppendedPath(Uri.withAppendedPath(
                        LooserProvider.CONTENT_URI, Database.Project.NAME), Long
                        .toString(id)));
                i.putExtra("spendino.de.ProjectDetail.position",position);
                startActivity(i);
            }
        });

    }

    class MySimpleCursorAdapter extends SimpleCursorAdapter {

        public MySimpleCursorAdapter(Context context, int layout, Cursor c,
                String[] from, int[] to) {
            super(context, layout, c, from, to);
            loader = new ImageLoaderCache(context);
            this.context = context;
        }
        Activity activity= ProjectsList.this;
        Context context=null;
        ImageLoaderCache loader = null;

        public void setViewImage(ImageView v, String value) {
            v.setTag(value);
            loader.displayImage(value, activity, v);
        }
    }


}

AKTUALISIERT, hier ist die LooserSync.java

public class LooserSync extends IntentService {

    public LooserSync() {
        super("LooserSyncService");
    }

    @Override
    protected void onHandleIntent(Intent intent) {
        Database.OpenHelper dbhelper = new Database.OpenHelper(getBaseContext());
        SQLiteDatabase db = dbhelper.getWritableDatabase();
        DefaultHttpClient httpClient = new DefaultHttpClient();
        db.beginTransaction();
        HttpGet request = new HttpGet(
                "http://liebenwald.spendino.net/admanager/dev/android/projects.json");
        try {
            HttpResponse response = httpClient.execute(request);
            if (response.getStatusLine().getStatusCode() == HttpStatus.SC_OK) {
                InputStream instream = response.getEntity().getContent();
                BufferedReader r = new BufferedReader(new InputStreamReader(
                        instream), 8000);
                StringBuilder total = new StringBuilder();
                String line;
                while ((line = r.readLine()) != null) {
                    total.append(line);
                }
                instream.close();
                String bufstring = total.toString();
                JSONArray arr = new JSONArray(bufstring);
                Database.Tables tab = Database.Tables.AllTables.get(Database.Project.NAME);
                tab.DeleteAll(db);
                for (int i = 0; i < arr.length(); i++) {
                    tab.InsertJSON(db, (JSONObject) arr.get(i));
                }
                db.setTransactionSuccessful();
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
        db.endTransaction();
        db.close();

    }

}