在设备中安装Android应用后找不到位置

Question

I have a problem.

I want to develop simple LBS apps using Android SDK which could determine my current location. I already made one, and tried it using emulator in eclipse.

As I know I have to use DDMS to send Latitude and Longitude value to Emulator, and yes it works. Now, I'd like to install it on my Android Device to determine whether it works or not in my mobile phone. But, It couldn't get my location.

I wonder what's wrong with it. Does internet or my cellphone provider determine my location (in exchange of using DDMS in eclipse) ? Or I need to add some lines of code to make it works or another configuration ?

This is my code :

public class PilihFitur extends Activity implements OnClickListener {

    private double mylat = 0.0;
    private double mylon = 0.0;
    private LocationManager locationManager = null;
    private Location location = null;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.pilihfitur);

        View goToMapsButton = findViewById(R.id.toMapsButton);
        goToMapsButton.setOnClickListener(this);
        View goToOrderButton = findViewById(R.id.toOrderButton);
        goToOrderButton.setOnClickListener(this);
    }

    @Override
    public void onClick(View v) {
        // TODO Auto-generated method stub
        switch (v.getId()) {
        case R.id.toMapsButton:
            onChangeLocation();
            break;
        default:
            break;
        }
    }

    private void onChangeLocation(){
        locationManager = (LocationManager)getSystemService(Context.LOCATION_SERVICE);
        locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 100, 10, new myLocationListener());
        location = locationManager.getLastKnownLocation(LocationManager.GPS_PROVIDER);
        if(location != null){
            mylat = location.getLatitude();
            mylon = location.getLongitude();
            Toast.makeText(PilihFitur.this, "Lokasi Anda: \nLat: "+mylat+" Lon: "+mylon, Toast.LENGTH_LONG).show();
        }
        else
            Toast.makeText(PilihFitur.this, "Lokasi Tidak Ditemukan", Toast.LENGTH_SHORT).show();
    }

    //Location Listener
    private class myLocationListener implements LocationListener{

        @Override
        public void onLocationChanged(Location arg0) {
            // TODO Auto-generated method stub

        }

        @Override
        public void onProviderDisabled(String arg0) {
            // TODO Auto-generated method stub

        }

        @Override
        public void onProviderEnabled(String arg0) {
            // TODO Auto-generated method stub

        }

        @Override
        public void onStatusChanged(String arg0, int arg1, Bundle arg2) {
            // TODO Auto-generated method stub

        }
            }
}

It works on emulator, I wonder how to make it work on my mobile phone. Thank you.

Answer 1

you check for location in the following method of location listener. try adding the code to this method, and check if you get location updates. sometimes, last known location can be null.

@Override
    public void onLocationChanged(Location location) {
    mylat = location.getLatitude();
    mylon = location.getLongitude();
    Toast.makeText(PilihFitur.this, "Lokasi Anda: \nLat: "+mylat+" Lon: "+mylon, Toast.LENGTH_LONG).show();


    }