我可以在距離達到之前停止位置更新嗎？

Question

   LocationManager lm = (LocationManager) getSystemService(Context.LOCATION_SERVICE); 

      LocationListener ll = new mylocationlistener(); 


       lm.requestLocationUpdates(LocationManager.GPS_PROVIDER, ????, 20, ll); 

1.如果只應用minDistance（20m），應輸入什麼minTime參數？ 0，-1或100000000？順便說一下，我想提示用戶已經到達距離原來地點20米的距離，但是當程序啓動並調用位置改變功能時，請求立即更新，我可以忽略位置改變功能，直到距離達到了？

Answer 1

試試這個（未經測試，而是基於the docs）：

final LocationManager locationManager = LocationManager lm = (LocationManager) getSystemService(Context.LOCATION_SERVICE); 
class implements LocationListener { 
    Location storedLocation; 
    public void onLocationChanged(Location newLocation) { 
     if (storedLocation.equals(null)) { 
      storedLocation = newLocation; 
     } 
     if ((newLocation.distanceTo(storedLocation) > 20.0) { 
      locationManager.removeUpdates(self); 
      return; 
     } 
     storedLocation = newLocation; 
    } 
    public void onProviderDisabled(String provider) { } 
    public void onProviderEnabled(String provider) { } 
    public void onStatusChanged(String provider, int status, Bundle extras) { } 
}