在作为后台进程的时间间隔内对webservice进行LocationListener和更新

Question

我的Andoid应用程序包含许多活动。我想运行一个独立于这些活动的后台进程(无论哪个活动在UI上运行)。在这个后台进程中，我希望使用LocationListener捕获位置更新，并希望调用web服务将捕获的位置存储在数据库中。并且此webservice调用必须仅在2分钟间隔内发生。有没有人可以帮我实现这个。

谢谢。Android开发者

Answer 1

看看这个

public class LocationUpdator extends Service{
    Location location;
    private int normallocationwait = 2000;
        Timer timer = new Timer();
        private final Handler handler = new Handler();
    Intent intent;

    public void  onCreate(){
        super.onCreate();
        intent = new Intent(BROADCAST_ACTION);  
        updateNotification();
    }

    //int onStartCommand(Intent intent, int flags, int startId) 
    public void onStart(Intent intent,int startId){
        super.onStart(intent, startId);
        handler.removeCallbacks(sendUpdatesToUI);
            handler.postDelayed(sendUpdatesToUI, 1000); // 1 second
        Log.v("Location Servics", "Start Service");
    }

    public void onDestroy(){
        super.onDestroy();
        Log.v("Location Servics", "Destroy Service");
    }


    protected void updateNotification() {
             LocationManager lm = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
             LocationListener locationListener = new MyLocationlistener();

             lm.requestLocationUpdates(LocationManager.GPS_PROVIDER, normallocationwait, 0.250f, locationListener);
             location = lm.getLastKnownLocation(LocationManager.GPS_PROVIDER);
        }

    private class MyLocationlistener implements LocationListener {

            public void onLocationChanged(Location location){
                 if(location!=null){
                           dumpLocation(location);
             } 
            }

         public void onProviderDisabled(String provider){
             Log.v("Loc Update","\nProvider disabled: " + provider);
         }

         public void onProviderEnabled(String provider){
             Log.v("Loc Update","\nProvider enabled: " + provider);
         }

         public void onStatusChanged(String provider, int status, Bundle extras){
             Log.v("Loc Update","\nProvider status changed: " + provider + ", status="
                        + status + ", extras=" + extras);
         }

         private void dumpLocation(Location location) {
                         Log.v("Loc Update","\n" + location.toString());
                     Log.v("Demo", location.toString());
                     if(GlobalValues.whereRegister == 1){
                             String url  = TaxiUrls.taxiLocationUpdate_url  + "taxi_device_id="+ GlobalValues.deviceID +
                                    "&lat="+ location.getLatitude() + "&lng=" + location.getLongitude();
                             Toast.makeText(getBaseContext(), "Location Update", Toast.LENGTH_SHORT).show();
                             HttpClient httpclient = new DefaultHttpClient();
                     HttpPost httppost = new HttpPost(url);
                     try {
                        HttpResponse response = httpclient.execute(httppost);
                            Log.v("Message", response.toString());
                     } catch (ClientProtocolException e) {
                        Log.e("Sending Message",e.getMessage().toString());
                     } catch (IOException e) {
                        Log.e("Sending Message",e.getMessage().toString());
                     }
                } 
            }

     }

}

Answer 2

也许值得在后台启动一个简单的AsyncTask来做这件事。