java - 地图显示起点。起点和终点是一样的。

Question

地图显示起点。为什么不显示来自数据库的调用标记。我不明白。或者编写代码显示数据库错误？

这段代码 Map.java

public class Map extends FragmentActivity implements LocationListener {

    SQLiteDatabase SQL;
    GoogleMap map;
    myDBClass DB;
    Cursor cursor;
    ArrayList<LatLng> MarkerPoint = new ArrayList<LatLng>();
    double latitude = 0;
    double longtitude = 0;
    GMapV2Direction md = new GMapV2Direction();
    Document document;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        // TODO Auto-generated method stub
        super.onCreate(savedInstanceState);
        setContentView(R.layout.show_map);
        if (android.os.Build.VERSION.SDK_INT > 9) {
            StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder().permitAll().build();
            StrictMode.setThreadPolicy(policy);
        }


        int status = GooglePlayServicesUtil.isGooglePlayServicesAvailable(getBaseContext());

        if (status != ConnectionResult.SUCCESS) {

            int requestCode = 10;
            Dialog dialog = GooglePlayServicesUtil.getErrorDialog(status, this,
                    requestCode);
            dialog.show();

        } else {

            //map = ((SupportMapFragment) getSupportFragmentManager().findFragmentById(R.id.map)).getMap();
            SupportMapFragment fm = (SupportMapFragment)getSupportFragmentManager().findFragmentById(R.id.map);
            map = fm.getMap();
            map.setMapType(GoogleMap.MAP_TYPE_NORMAL);
            map.setMyLocationEnabled(true);

            LocationManager locationManager = (LocationManager) getSystemService(LOCATION_SERVICE);
            Criteria criteria = new Criteria();
            String provider = locationManager.getBestProvider(criteria, true);
            Location location = locationManager.getLastKnownLocation(provider);

            if (location != null) {
                onLocationChanged(location);
            }
            locationManager.requestLocationUpdates(provider, 20000, 0, this);


            // Destination Marker from Database SQLite
            if (MarkerPoint.size() > 1) {
                String Name = getIntent().getStringExtra("Name");
                DB = new myDBClass(this);
                SQL = DB.getWritableDatabase();

                cursor = SQL.rawQuery("SELECT *" + " FROM "
                        + myDBClass.TABLE_NAME + " WHERE " + myDBClass.NAME
                        + " ='" + Name + "'", null);

                cursor.moveToFirst();
                /**String name = cursor.getString(cursor.getColumnIndex(myDBClass.NAME));
                double lat_db = cursor.getDouble(cursor.getColumnIndex(myDBClass.LAT));
                double lng_db = cursor.getDouble(cursor.getColumnIndex(myDBClass.LNG));
                map.addMarker(new MarkerOptions() 
                .position(new LatLng(lat_db, lng_db)) .title(name));**/
                latitude = cursor.getDouble(cursor.getColumnIndex(myDBClass.LAT));
                longtitude = cursor.getDouble(cursor.getColumnIndex(myDBClass.LNG));
                cursor.moveToNext();
                //MarkerPoint.clear();
                //map.clear();
                LatLng strpoint = new LatLng(latitude, longtitude);
                drawMarker(strpoint);
            }

        }


        DrawRouteTask drawroute = new DrawRouteTask();
        drawroute.execute();

    }

    private class DrawRouteTask extends AsyncTask<String, Void, String> {

        private ProgressDialog Dialog;
        String response = "";

        @Override
        protected void onPreExecute() {

            Dialog = new ProgressDialog(Map.this);
            Dialog.setMessage("Loading");
            Dialog.show();
        }

        @Override
        protected String doInBackground(String... urls) {

            // Get All Route values
            if (MarkerPoint.size() >= 2) {
                LatLng Start = MarkerPoint.get(0);
                LatLng End = MarkerPoint.get(1);
            document = md.getDocument(Start, End,GMapV2Direction.MODE_DRIVING);
            response = "Success";
            }
            return response;
        }

        @Override
        protected void onPostExecute(String result) {

            try {
                if (response.equalsIgnoreCase("Success")) {
                    ArrayList<LatLng> directionPoint = md.getDirection(document);
                    PolylineOptions rectLine = new PolylineOptions().width(10).color(Color.RED);
                    for (int i = 0; i < directionPoint.size(); i++) {
                        rectLine.add(directionPoint.get(i));
                    }
                    // Adding route on the map
                    map.addPolyline(rectLine);
                }
            } catch (Exception e) {
                // TODO:ERROR TRACE ROUTE
            }
            Dialog.dismiss();
        }
    }

    private void drawMarker(LatLng point) {
        MarkerPoint.add(point);

        MarkerOptions options = new MarkerOptions();

        options.position(point);

        if (MarkerPoint.size() == 1) {
            options.icon(BitmapDescriptorFactory
                    .defaultMarker(BitmapDescriptorFactory.HUE_GREEN));
        } else if (MarkerPoint.size() == 2) {
            options.icon(BitmapDescriptorFactory
                    .defaultMarker(BitmapDescriptorFactory.HUE_RED));
        }
        map.addMarker(options);
    }

    @Override
    public void onLocationChanged(Location location) {
        // TODO Auto-generated method stub
        if (MarkerPoint.size() < 2) {

            latitude = location.getLatitude();
            longtitude = location.getLongitude();
            LatLng point = new LatLng(latitude, longtitude);

            map.moveCamera(CameraUpdateFactory.newLatLng(point));
            map.animateCamera(CameraUpdateFactory.zoomTo(6));

            drawMarker(point);
        }
    }

    @Override
    public void onProviderDisabled(String provider) {
        // TODO Auto-generated method stub

    }

    @Override
    public void onProviderEnabled(String provider) {
        // TODO Auto-generated method stub

    }

    @Override
    public void onStatusChanged(String provider, int status, Bundle extras) {
        // TODO Auto-generated method stub

    }

http://i.stack.imgur.com/SXq5P.jpg

地图显示起点。为什么不显示来自数据库的调用标记。我不明白。或者编写代码显示数据库错误？