在IntentService中使用LocationManager似乎不起作用

Question

我在我的IntentService中使用LocationManager时遇到问题。我正在开发一个应用程序来显示地图图像。我想要一个IntentService运行背景来检测位置更改。当检测到位置更新时，服务会将新位置写入SQLite数据库。 IntentService将发送一个广播给主Activity，让它知道一个新的位置已被存储。主应用程序提取数据库的位置并将图标移动到地图上的新位置。

下面是服务代码：

import java.util.List; 
import java.io.*; 

import android.os.AsyncTask; 
import android.os.Bundle; 

import android.app.IntentService; 
import android.content.Context; 
import android.content.Intent; 

import android.widget.Toast; 

import android.location.GpsStatus; 
import android.location.Location; 
import android.location.LocationListener; 
import android.location.GpsStatus.NmeaListener; 

import android.location.LocationManager; 

import android.database.*; 

import android.util.Log; 

// local imports 
import com.saic.MCAppActivity; 
import com.saic.db.*; 

public class SaService extends IntentService { 

    private static final String tag = "SaService"; 


    private Location loc = null; 
    private Intent updateMapIntent = null; 
    private LocationManager locMgr = null; 
    private boolean gps_provider = false; 
    private boolean net_provider = false; 

    public SaService() 
    { 
     super(tag); 
    } 

    public SaService(String name) 
    { 
     super(name); 
    } 

    @Override 
    protected void onHandleIntent(Intent intent) 
    { 
     updateMapIntent = new Intent(); 
     updateMapIntent.setAction("UPDATE_LOCATION"); 

     locMgr = MCAppActivity.getLocationManager(); 

     locMgr.requestLocationUpdates(LocationManager.GPS_PROVIDER, 60, 0, 
             locationListener); 
     locMgr.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 60, 0, 
             locationListener); 

     // loop until told to quit 
     while (!MCAppActivity.toQuit()) 
     { 
      try { 
      Thread.sleep(30000); 
      } 
      catch (InterruptedException e) {} 
      getBaseContext().sendBroadcast(updateMapIntent); 
     } 
     stopSelf(); 
    } 


    LocationListener locationListener = new LocationListener() { 
     public void onLocationChanged(Location location) { 
      double lat = 0.0; 
      double lon = 0.0; 

      // Called when a new location is found by the network location provider. 
      if (location.getProvider().equals(LocationManager.GPS_PROVIDER)) 
      { 
       lat = location.getLatitude(); 
       lon = location.getLongitude(); 
       Log.i(tag, "LocationListener(): gps_provider location update:\nlat: " + lat + 
               "\nlon: " + lon); 
       writeLocationToDB(location); 
      } 
      else if (location.getProvider().equals(LocationManager.NETWORK_PROVIDER)) 
      { 
       lat = location.getLatitude(); 
       lon = location.getLongitude(); 
       Log.i(tag, "LocationListener(): net_provider location update:\nlat: " + lat + 
         "\nlon: " + lon); 
       writeLocationToDB(location); 
      } 
      else 
      { 
       Log.i(tag, "LocationListener(): unknown provider found"); 
      } 
     } 

     // don't need them now. make them NO-OP 
     public void onStatusChanged (String provider, int status, Bundle extras) {} 
     public void onProviderEnabled (String provider) 
     { 
      Log.i(tag, "enable gps: "+ provider); 
     } 
     public void onProviderDisabled (String provider) 
     { 
      Log.w(tag, "disable gps: "+ provider); 
     } 

    }; 

} 

中的LocationManager在我MCAppActivity定义，并传递给服务。在手机上运行应用程序时，我没有遇到任何错误。但是，侦听器从不被调用。在服务中调用LocationManager与调用Activity相比是否存在问题？我知道我必须将minTime更改为更大的值以避免电池耗尽。现在，我只想看看我能否实现它。

在此先感谢。

Answer 1

对不起，重新启动线程。

为什么不直接使用一个普通的服务：

public class MyService extends Service { 

    private static final String TAG = "MyService"; 
    private LocationManager lm; // somewhere initialized 
    private LocationListener ll; // somewhere initialized 


    @Override 
    public void onCreate() { 
    super.onCreate(); 
    lm.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 0, 0, ll,Looper.getMainLooper()); 
    } 

    @Override 
    public void onDestroy() { 
    lm.removeUpdates(ll); 
    super.onDestroy(); 
    } 
}