在android中的谷歌地图上绘制多个标记

我是android领域的新手。我写了一个安卓应用1将从网络提供商检索纬度和经度值并将其存储在我的本地服务器（LAMP）中。

我还创建了一个 MYSQL DB 表，该表有 3 列（lat、lon、id），其中包含使用网络提供程序检索的值（lat 和 lon）。目前我的表中有超过 10 个值。

我已经创建了 JSON 对象，用于使用 PHP 脚本从 MYSQL DB 获取这些值安卓应用2

所有这些都运行良好。我现在要做的是创建一个 MapActivity，它将使用 Marker 在地图上绘制这些纬度和经度值。我试图将其绘制在地图上，但我在地图上只得到了我的最后一个位置（表中的最后一个纬度和经度值）。

如何在地图上绘制我的所有点。以下是我尝试过的代码，但它无法正常工作。请帮助我纠正我的错误。

public class ShowMapActivity extends MapActivity {
String returnString;
String returnString1;
double aa1 ;
double  aa2;

  private MapController mapController;
  private MapView mapView;
  private LocationManager locationManager;
  private MyOverlay itemizedoverlay;
  private MyLocationOverlay myLocationOverlay;

  public void onCreate(Bundle bundle) {

    super.onCreate(bundle);
    setContentView(R.layout.main); // bind the layout to the activity


    // Configure the Map
    mapView = (MapView) findViewById(R.id.mapview);
    mapView.setBuiltInZoomControls(true);
    //mapView.setSatellite(true);
    mapController = mapView.getController();
    mapController.setZoom(14); // Zoon 1 is world view
    locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);


    myLocationOverlay = new MyLocationOverlay(this, mapView);
    mapView.getOverlays().add(myLocationOverlay);

    myLocationOverlay.runOnFirstFix(new Runnable() {
      public void run() {
        mapView.getController().animateTo(myLocationOverlay.getMyLocation());
      }
    });

    Drawable drawable = this.getResources().getDrawable(R.drawable.ic_launcher);
    itemizedoverlay = new MyOverlay(this, drawable);
    createMarker();
  }

  @Override
  protected boolean isRouteDisplayed() {
    return false;
  }
      private void createMarker() {
    GeoPoint p = mapView.getMapCenter();
    OverlayItem overlayitem = new OverlayItem(p, "", "");
    itemizedoverlay.addOverlay(overlayitem);
    if (itemizedoverlay.size() > 0) {
      mapView.getOverlays().add(itemizedoverlay);
    }
  }

  @Override
  protected void onResume() {
    super.onResume();
    myLocationOverlay.enableMyLocation();
    myLocationOverlay.enableCompass();
  }

  @Override
  protected void onPause() {
    super.onPause();
    myLocationOverlay.disableMyLocation();
    myLocationOverlay.disableCompass();
  }



  public class GetMethodEx {

        public String getInternetData() throws Exception {

            BufferedReader in = null;
            String data = "";

            //String returnString = null;

            // httpGet

            try {

                HttpClient client = new DefaultHttpClient();
                URI website = new URI("http://192.168.1.15/latlonret1.php");
                HttpGet request = new HttpGet();
                request.setURI(website);
                HttpResponse response = client.execute(request);
                in = new BufferedReader(new InputStreamReader(response
                        .getEntity().getContent()));
                StringBuffer sb = new StringBuffer("");
                String l = "";
                String nl = System.getProperty("line.separator");

                while ((l = in.readLine()) != null) {
                    sb.append(l + nl);
                }
                in.close();
                data = sb.toString();
                // return data;
            } catch (Exception e) {
                Log.e("log_tag", "Error converting result " + e.toString());
            }


            // parse json data
            try {

                JSONArray jArray = new JSONArray(data);


                for (int i = 0; i < jArray.length(); i++) {
                    JSONObject json_data = jArray.getJSONObject(i);
                    JSONObject json_data1 = jArray.getJSONObject(i);


                    returnString =json_data.getString("lat") + "\n";
                    returnString1 =json_data1.getString("lon") + "\n";
                    System.out.println(returnString);
                    System.out.println(returnString1);
              }

         Bundle bundle = new Bundle();
         bundle.putString("stuff", returnString); 
         bundle.putString("stuff1", returnString1); 

         try
         {
             aa1=Double.valueOf(returnString);
             aa2=Double.valueOf(returnString1);
         }
         catch(Exception e)
         {

         }

           System.out.println(returnString);
           System.out.println(returnString1);
            }



            catch (JSONException e) {
                Log.e("log_tag", "Error parsing data " + e.toString());
            }

            return returnString;

        }  
  }
      }

This可能有帮助。 SO 上也有很多例子。