How to use httpUtils in a Service module?

'Service module
Sub Process_Globals
   'These global variables will be declared once when the application starts.
   'These variables can be accessed from all modules.
   Dim SQL As SQL
   Dim gps1 As GPS
   Dim pid As PhoneId
      Dim domainName As String
   Dim servicePath As String
   Dim serviceName As String
   Dim StrUtils As StringUtils
End Sub
Sub Service_Create
   Dim s As String
   s=DBUtils.CopyDBFromAssets("gpsdb.db")
   SQL.Initialize(s,"gpsdb.db",False)
   gps1.Initialize("GPS")
      domainName = "192.168.7.5:9022"
   httpUtils.CallbackActivity="GPSService"
   httpUtils.CallbackJobDoneSub="JobDone"
   httpUtils.CallbackUrlDoneSub="UrlDone"
'   domainName = manager.GetString("key1") 
   servicePath = "/datasnap/rest/TService/"
   serviceName = "http://"&domainName&servicePath
End Sub

Sub Service_Start (StartingIntent As Intent)
   
   If GPS1.GPSEnabled = False Then
      ToastMessageShow("Please enable the GPS device.", True)
      StartActivity(GPS1.LocationSettingsIntent) 'Will open the relevant settings screen.
   Else
      GPS1.Start(1000*60, 0) '参数1：间隔的毫秒，参数2：间隔的米
   End If

End Sub

Sub Service_Destroy
   gps1.Stop
   Log("GPS Stop")
End Sub

Sub GPS_LocationChanged (Location1 As Location)

   
   Log("Latiitude="&Location1.Latitude)
   Log("Longitude="&Location1.Longitude)
   Log("Time="&Location1.Time)
   Log( "Speed = " & Location1.Speed)
   Log("Now="&DateTime.Now)
   Log("IMSI="&pid.GetSubscriberId)
   
   Dim ListOfMaps As List
   ListOfMaps.Initialize
   'Dim id As Int
   Dim m As Map
   m.Initialize
   m.Put("Long", Location1.Longitude)
   m.Put("Lat", Location1.Latitude)
   m.Put("GetTime",DateTime.Now)
   m.Put("IMSI",pid.GetSubscriberId)
   ListOfMaps.Add(m)
   DBUtils.InsertMaps(SQL, "gpsInfo", ListOfMaps)
   Dim s As String
   DateTime.DateFormat = "yyyy-MM-dd"
   s = serviceName&"getMapPosition/"&StrUtils.EncodeUrl(Location1.Longitude, "UTF8")&"/"&StrUtils.EncodeUrl(Location1.Latitude, "UTF8")&"/"&StrUtils.EncodeUrl(DateTime.Date(DateTime.Now), "UTF8")&"/"&StrUtils.EncodeUrl(pid.GetSubscriberId, "UTF8")
   httpUtils.PostString(s, s, ListOfMaps)
End Sub


Sub JobDone(Job As String)
   Dim s As String
   
   If HttpUtils.IsSuccess(job) Then
      s = httpUtils.GetString(job)
      Log(s)   
   End If 
End Sub
Sub UrlDone(Url As String)
   Log(Url & "done")
End Sub