Cannot send a string to another class

i am working with android program here i have two classes PlaceMapActivity and AddItemizedOverlay i want to send a string from PlaceMapActivity to the AddItemizedOverlay class can any one help me to solve this and here is my two classes

AddItemizedOverlay

public class AddItemizedOverlay extends ItemizedOverlay<OverlayItem> {

       private ArrayList<OverlayItem> mapOverlays = new ArrayList<OverlayItem>();

       private Context context;
       String reference;
       private Activity activity;

       String p_u_name;
       String username;
       public AddItemizedOverlay(Drawable defaultMarker) {
            super(boundCenterBottom(defaultMarker));
       }

       public AddItemizedOverlay(Drawable defaultMarker, Context context) {
            this(defaultMarker);
            this.context = context;
       }



       @Override
       public boolean onTouchEvent(MotionEvent event, MapView mapView)
       {   
               if (event.getAction() == 1) {
               GeoPoint geopoint = mapView.getProjection().fromPixels(
                   (int) event.getX(),
                   (int) event.getY());
               // latitude
               double lat = geopoint.getLatitudeE6() / 1E6;
               // longitude
               double lon = geopoint.getLongitudeE6() / 1E6;
               //Toast.makeText(context, "Lat: " + lat + ", Lon: "+lon, Toast.LENGTH_SHORT).show();
           }
           return false;
       } 

       @Override
       protected OverlayItem createItem(int i) {
          return mapOverlays.get(i);
       }
       @Override
       public int size() {
          return mapOverlays.size();
       }

      @Override
       protected boolean onTap(int index) {
         OverlayItem item = mapOverlays.get(index);
         AlertDialog.Builder dialog = new AlertDialog.Builder(this.context);
         dialog.setTitle(item.getTitle());
         dialog.setMessage("Do you want ot park here ?");
         reference = item.getSnippet();
         dialog.setPositiveButton("Yes", new DialogInterface.OnClickListener() {
            public void onClick(DialogInterface dialog, int which) {


                SharedPreferences prefs = context.getSharedPreferences("myprefs", 0);
                SharedPreferences.Editor editor =prefs.edit();
                editor.putString("KEY_REFERENCE", reference);
                editor.commit();                

                Intent intent = new Intent(context, SinglePlaceActivity.class);
                intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
                context.startActivity(intent);
            }
         })
            .setNegativeButton("No",new DialogInterface.OnClickListener() {
                public void onClick(DialogInterface dialog,int id) {
                    // if this button is clicked, just close
                    // the dialog box and do nothing
                    dialog.cancel();
//                  MainActivity.this.finish();
                }
            });
         dialog.show();
         return true;
       }

       public void addOverlay(OverlayItem overlay) {
          mapOverlays.add(overlay);
       }

       public void populateNow(){
           this.populate();
       }

    }

and the second class is here

PlacesMapActivity.java

public class PlacesMapActivity extends MapActivity {
    // Nearest places
    PlacesList nearPlaces;

    // Map view
    MapView mapView;

    // Map overlay items
    List<Overlay> mapOverlays;

    AddItemizedOverlay itemizedOverlay;

    GeoPoint geoPoint;
    // Map controllers
    MapController mc;

    double latitude;
    double longitude;
    OverlayItem overlayitem,wma;

    String p_u_name;
    Place reference;



    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.map_places);

        // Getting intent data
        Intent i = getIntent();

        p_u_name = i.getExtras().getString("KEY_USERNAME");

//      AddItemizedOverlay its_obj = new AddItemizedOverlay(null);
//      its_obj.getstring(p_u_name);

        System.out.println("place map activity :got username"+p_u_name);

        reference = (Place) i.getSerializableExtra("place_reference");

        // Users current geo location
        String user_latitude = i.getStringExtra("user_latitude");
        String user_longitude = i.getStringExtra("user_longitude");

        System.out.println("sarath"+user_latitude + user_longitude);

        // Nearplaces list
        nearPlaces = (PlacesList) i.getSerializableExtra("near_places");

        mapView = (MapView) findViewById(R.id.mapView);
        mapView.setBuiltInZoomControls(true);

        mapOverlays = mapView.getOverlays();

        // Geopoint to place on map
        geoPoint = new GeoPoint((int) (Double.parseDouble(user_latitude) * 1E6),(int) (Double.parseDouble(user_longitude) * 1E6));

        // Drawable marker icon
        Drawable drawable_user = this.getResources().getDrawable(R.drawable.mark_red);

        itemizedOverlay = new AddItemizedOverlay(drawable_user, this);

        // Map overlay item
        overlayitem = new OverlayItem(geoPoint, "Your Location","That is you!");

        itemizedOverlay.addOverlay(overlayitem);

        mapOverlays.add(itemizedOverlay);
        itemizedOverlay.populateNow();

        // Drawable marker icon
        Drawable drawable = this.getResources().getDrawable(R.drawable.mark_blue);

        itemizedOverlay = new AddItemizedOverlay(drawable, this);

        mc = mapView.getController();

        // These values are used to get map boundary area
        // The area where you can see all the markers on screen
        int minLat = Integer.MAX_VALUE;
        int minLong = Integer.MAX_VALUE;
        int maxLat = Integer.MIN_VALUE;
        int maxLong = Integer.MIN_VALUE;

        // check for null in case it is null
        if (nearPlaces.results != null) {
            // loop through all the places
            for (Place place : nearPlaces.results) {

                latitude = place.geometry.location.lat; // latitude
                longitude = place.geometry.location.lng; // longitude

                // Geopoint to place on map
                geoPoint = new GeoPoint((int) (latitude * 1E6),
                        (int) (longitude * 1E6));

                // Map overlay item
                overlayitem = new OverlayItem(geoPoint,place.name,place.reference);

                itemizedOverlay.addOverlay(overlayitem);

                // calculating map boundary area
                minLat  = (int) Math.min( geoPoint.getLatitudeE6(), minLat );
                minLong = (int) Math.min( geoPoint.getLongitudeE6(), minLong);
                maxLat  = (int) Math.max( geoPoint.getLatitudeE6(), maxLat );
                maxLong = (int) Math.max( geoPoint.getLongitudeE6(), maxLong );
            }
            mapOverlays.add(itemizedOverlay);

            // showing all overlay items
            itemizedOverlay.populateNow();
        }

        // Adjusting the zoom level so that you can see all the markers on map
        mapView.getController().zoomToSpan(Math.abs( minLat - maxLat ), Math.abs( minLong - maxLong ));

        // Showing the center of the map
        mc.animateTo(new GeoPoint((maxLat + minLat)/2, (maxLong + minLong)/2 ));
        mapView.postInvalidate();

    }

    @Override
    protected boolean isRouteDisplayed() {
        return false;
    }
}

Semd String when you create AddItemizedOverlay class object.

Write this in your activity class

  itemizedOverlay = new AddItemizedOverlay(drawable_user, this,StringData);

Write this in your OverLay class

private String StringData;

public AddItemizedOverlay(Drawable defaultMarker, Context context,String StringData) {
            this(defaultMarker);
            this.context = context;
this.StringData=StringData;
       }

Try this way....

Thanks