無法使用GPS

Question

我是新來的android編程。我有一個線程，我已經請求位置更新。問題是onLocationChanged(Location loc)中的代碼從未得到執行。請解釋我如何解決這個問題。

public void run() { 

    Looper.prepare(); 

     while (isMyServiceRunning()) { 

      try { 
       Thread.sleep(3000); 

      } catch (InterruptedException e) { 

       e.printStackTrace(); 
      } 


      try { 
       Log.d("spt", "read status started"); 
       if ((Connectivity.isConnected(getApplicationContext()))) { 
        URL urlreadstatus = new URL("http://asd.fgh.com/status.txt"); 
       // Log.d("spt",String.valueOf(URLUtil.isValidUrl("http://asd.fgh.com/status.txt"))); 
        BufferedReader in = new BufferedReader(new InputStreamReader(urlreadstatus.openStream())); 
        str = in.readLine(); 
        if(!str.equals(null)){ 
         Log.d("spt", str); 
        } 
        in.close(); 
        Log.d("spt", "read status complete"); 
       } else { 
        Log.d("spt", "not connected"); 
        break; 
       } 

      } catch (MalformedURLException e1) { 

       e1.printStackTrace(); 
      } catch (IOException e) { 

       Log.d("spt", "IO exception"); 
       str = "11"; 
       e.printStackTrace(); 
      } catch(NullPointerException e){ 
       str="11"; 
      } 
      if (str.equals(null)) { 
       str = "11";    
      } 
      if (str.length() == 1) { 
       loststatus++; 
       LocationManager l; 
       l=(LocationManager) getSystemService(Context.LOCATION_SERVICE); 
       Criteria criteria = new Criteria(); 
       provider = l.getBestProvider(criteria, false); 
       l.requestLocationUpdates("gps", 400, 1, this); 
       Log.d("spt", "lost status=1 requesting location updates"); 

      } else { 
       loststatus = 0; 
      } 

     } 

    } 
@Override 
    public void onLocationChanged(Location loc) { 
     // TODO Auto-generated method stub 
     Log.d("spt", "in loc changed"); 
     double longi = loc.getLongitude(); 
     double lati = loc.getLatitude(); 
     double acc=loc.getAccuracy(); 
     Log.d("spt", String.valueOf(acc)); 
     if (loststatus > 0) { 

      HttpPost httpPost = new HttpPost(
        "http://asd.fgh.com/writegps.php?value=" 
          + String.valueOf(lati) + "," 
          + String.valueOf(longi)); 
      // output is the variable you used in your program 
      try { 
       DefaultHttpClient httpClient = new DefaultHttpClient(); 

       httpClient.execute(httpPost); 
       Log.d("spt", "writing coord to file"); 

      } catch (ClientProtocolException e) { 
       // TODO Auto-generated catch block 
       e.printStackTrace(); 
      } catch (IOException e) { 
       // TODO Auto-generated catch block 
       e.printStackTrace(); 
      } 

      Toast.makeText(this, String.valueOf(lati) + String.valueOf(longi), 
       Toast.LENGTH_SHORT).show(); 

     } 
    } 

Answer 1

嘗試建立一個位置監聽器如下，作爲並列在您的類實現一個（我假設你沒有在外面的視線代碼）：

private void setupLocationUpdates() { 

    // Acquire a reference to the system Location Manager 
    mLocationManager = (LocationManager) this.getSystemService(Context.LOCATION_SERVICE); 
    // Define a listener that responds to location updates 
    mLocationListener = new LocationListener() { 
     // Called when the location has changed. 
     public void onLocationChanged(Location location) { 
      mLocation = location; 
      // DO SOMETHING HERE 
     } 
     }; 
    mlocationProvider = LocationManager.GPS_PROVIDER; 
    // Register for location updates 
    mLocationManager.requestLocationUpdates(mlocationProvider, 0, 0, mLocationListener); 
}