how could this work with eclipse, but not in an actual phone?

 LocationManager locationManager;
    String context = Context.LOCATION_SERVICE;
    locationManager = (LocationManager)getSystemService(context);
    Criteria criteria = new Criteria();
    criteria.setAccuracy(Criteria.ACCURACY_FINE);
    criteria.setAltitudeRequired(false);
    criteria.setBearingRequired(false);
    criteria.setCostAllowed(true);
    criteria.setPowerRequirement(Criteria.POWER_LOW);

    String provider = locationManager.getBestProvider(criteria, true);
    Location location = locationManager.getLastKnownLocation(provider);
    double latitude = location.getLatitude();
    double longitude = location.getLongitude();

Just after that i take the latitude and the longitude to put in on a server, but it 开发者_开发技巧crash my phone.

Settings>Location and Security>My Location

service is not enabled into your Android device

hence yourlocationManager.getLastKnownLocation(provider) ( If the provider is currently disabled, null is returned.) is producing null value, Later then you are invoking double latitude = location.getLatitude(); double longitude = location.getLongitude(); with a null value object, so your application is crashing.