在Android中的谷歌地图上绘制多个标记

Question

我是android领域的新手。我编写了一个 android App1 ，它将从网络提供程序中检索纬度和经度值，并将其存储在我的本地服务器（LAMP）中。

我还创建了一个MYSQL数据库表，它有3列（lat，lon，id），它们具有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。

我创建了JSON对象，用于在 Android App2

中使用PHP脚本从MYSQL DB获取这些值

所有这些都很好。我现在要做的是创建一个MapActivity，它将使用Marker在地图上绘制那些lat和lon值。我试图在地图上绘制它，但我在地图上只得到我的最后一个位置（我的表中的最后一个lat和lon值）。

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

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;

        }  
  }
      }

Answer 1

This可能有所帮助。 SO上也有很多例子。