Network location provider not giving location andr

问题:

I am developing a small android application in which I want to find out the user's current location by using the network provider. I tried this in following ways but it's not giving me any output :

networklocationManager = (LocationManager) this
        .getSystemService(Context.LOCATION_SERVICE);
// Define a listener that responds to location updates
LocationListener networklocationListener = new LocationListener() {

    public void onLocationChanged(Location location) {
        Log.i("********************************",
                "this is my network location " + location);
        String Location_text = "NETWORK LOCATION latitude:"
                + location.getLatitude() + " longitude:"
                + location.getLatitude();
        network_location.setText(Location_text);
    }

    public void onStatusChanged(String provider, int status,
            Bundle extras) {}

    public void onProviderEnabled(String provider) {}

    public void onProviderDisabled(String provider) {}
};
// Register the listener with the Location Manager to receive location
// updates
networklocationManager
        .requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 0, 0,
                networklocationListener);

I gave permissions in my manifest file like this

 <uses-permission 
    android:name="android.permission.INTERNET" />
<uses-permission
    android:name="android.permission.ACCESS_COARSE_LOCATION" />
 <uses-permission
    android:name="android.permission.ACCESS_FINE_LOCATION" /> 

Is there any thing which I am missing ? Is this the correct way? Need help. Thank you...

---

public class MainActivity extends Activity implements LocationListener {

    private TextView latituteField;
    private TextView longitudeField;
    private LocationManager gpslocationManager;
    private LocationManager networklocationManager;
    private LocationManager networklocationManager1;
    private String provider;
    private TextView gps_location;
    private TextView network_location;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        gps_location = (TextView) findViewById(R.id.gps_location);
        network_location = (TextView) findViewById(R.id.network_location);
        networkLocation();
    }

    public void networkLocation() {
        networklocationManager = (LocationManager) this
                .getSystemService(Context.LOCATION_SERVICE);
        LocationListener networklocationListener = new LocationListener() {

            public void onLocationChanged(Location location) {
                Log.i("********************************",
                        "this is my network location " + location);
                String Location_text = "NETWORK LOCATION latitude:"
                        + location.getLatitude() + " longitude:"
                        + location.getLatitude();
                network_location.setText(Location_text);
            }

            public void onStatusChanged(String provider, int status,
                    Bundle extras) {}

            public void onProviderEnabled(String provider) {}

            public void onProviderDisabled(String provider) {}
        };
        networklocationManager
                .requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 0, 0,
                        networklocationListener);
    }
}

回答1:

Make sure you enable Location Services in Settings! That should be the problem. It might be disabled (and this setting will usually be found in Location and Security in Settings)

Let me know if it works!

回答2:

Is your network provider enabled?

boolean network_enabled;
try {
    network_enabled = locManager.isProviderEnabled(LocationManager.NETWORK_PROVIDER);
} catch(Exception ex) {
   ex.printStackTrace();
}

回答3:

I hope this part of the code will help you extracted from vogella.

public class ShowLocationActivity extends Activity implements LocationListener {

    private TextView latituteField;
    private TextView longitudeField;
    private LocationManager locationManager;
    private String provider;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        latituteField = (TextView) findViewById(R.id.TextView02);
        longitudeField = (TextView) findViewById(R.id.TextView04);
        // Get the location manager
        locationManager = (LocationManager) 
                getSystemService(Context.LOCATION_SERVICE);
        // Define the criteria how to select the locatioin provider -> use
        // default
        Criteria criteria = new Criteria();
        provider = locationManager.getBestProvider(criteria, false);
        Location location = locationManager.getLastKnownLocation(provider);
        // Initialize the location fields
        if (location != null) {
            System.out.println("Provider " + provider + " has been selected.");
            onLocationChanged(location);
        } else {
            latituteField.setText("Location not available");
            longitudeField.setText("Location not available");
        }
    }

    /* Request updates at startup */
    @Override
    protected void onResume() {
        super.onResume();
        locationManager.requestLocationUpdates(provider, 400, 1, this);
    }

    /* Remove the locationlistener updates when Activity is paused */
    @Override
    protected void onPause() {
        super.onPause();
        locationManager.removeUpdates(this);
    }

    @Override
    public void onLocationChanged(Location location) {
        int lat = (int) (location.getLatitude());
        int lng = (int) (location.getLongitude());
        latituteField.setText(String.valueOf(lat));
        longitudeField.setText(String.valueOf(lng));
    }

    @Override
    public void onStatusChanged(String provider, int status, Bundle extras) {}

    @Override
    public void onProviderEnabled(String provider) {
        Toast.makeText(this, "Enabled new provider " + provider,
            Toast.LENGTH_SHORT).show();
    }

    @Override
    public void onProviderDisabled(String provider) {
        Toast.makeText(this, "Disabled provider " + provider,
            Toast.LENGTH_SHORT).show();
    }
}