如何获取Google Maps Android API v2中的当前位置？

Question

Using

mMap.setMyLocationEnabled(true)

can set the myLocation layer enable.
But the problem is how to get the myLocation when the user clicks on the button? I want to get the longitude and latitude.

Answer 1

The Google Maps API location now works, even has listeners, you can do it using that, for example:

private GoogleMap.OnMyLocationChangeListener myLocationChangeListener = new GoogleMap.OnMyLocationChangeListener() {
    @Override
    public void onMyLocationChange(Location location) {
        LatLng loc = new LatLng(location.getLatitude(), location.getLongitude());
        mMarker = mMap.addMarker(new MarkerOptions().position(loc));
        if(mMap != null){
            mMap.animateCamera(CameraUpdateFactory.newLatLngZoom(loc, 16.0f));
        }
    }
};

and then set the listener for the map:

mMap.setOnMyLocationChangeListener(myLocationChangeListener);

This will get called when the map first finds the location.

No need for LocationService or LocationManager at all.

OnMyLocationChangeListener interface is deprecated. use com.google.android.gms.location.FusedLocationProviderApi instead. FusedLocationProviderApi provides improved location finding and power usage and is used by the "My Location" blue dot. See the MyLocationDemoActivity in the sample applications folder for example example code, or the Location Developer Guide.

Answer 2

At the moment GoogleMap.getMyLocation() always returns null under every circumstance.

There are currently two bug reports towards Google, that I know of, Issue 40932 and Issue 4644 .

Implementing a LocationListener as brought up earlier would be incorrect because the LocationListener would be out of sync with the LocationOverlay within the new API that you are trying to use.

Following the tutorial on Vogella's Site, linked earlier by Pramod J George, would give you directions for the Older Google Maps API.

So I apologize for not giving you a method to retrieve your location by that means. For now the locationListener may be the only means to do it, but I'm sure Google is working on fixing the issue within the new API.

Also sorry for not posting more links, StackOverlow thinks I'm spam because I have no rep.

---- Update on February 4th, 2013 ----

Google has stated that the issue will be fixed in the next update to the Google Maps API via Issue 4644 . I am not sure when the update will occur, but once it does I will edit this post again.

---- Update on April 10th, 2013 ----

Google has stated the issue has been fixed via Issue 4644 . It should work now.

Answer 3

try this

LocationManager service = (LocationManager) getSystemService(LOCATION_SERVICE);
Criteria criteria = new Criteria();
String provider = service.getBestProvider(criteria, false);
Location location = service.getLastKnownLocation(provider);
LatLng userLocation = new LatLng(location.getLatitude(),location.getLongitude());

Answer 4

Ensure that you have turned ON the location services on the device. Else you won't get any location related info.

This works for me,

    map = ((MapFragment)getFragmentManager().findFragmentById(R.id.map)).getMap();
    map.setMyLocationEnabled(true);
    GoogleMap.OnMyLocationChangeListener myLocationChangeListener = new GoogleMap.OnMyLocationChangeListener() {
        @Override
        public void onMyLocationChange (Location location) {
           LatLng loc = new LatLng (location.getLatitude(), location.getLongitude());
           map.animateCamera(CameraUpdateFactory.newLatLngZoom(loc, 16.0f));
        }
    };
    map.setOnMyLocationChangeListener(myLocationChangeListener);

}

Answer 5

To get the location when the user clicks on a button call this method in the onClick-

void getCurrentLocation() {
    Location myLocation  = mMap.getMyLocation();
    if(myLocation!=null)
    {
        double dLatitude = myLocation.getLatitude();
        double dLongitude = myLocation.getLongitude();
        Log.i("APPLICATION"," : "+dLatitude);
        Log.i("APPLICATION"," : "+dLongitude);
        mMap.addMarker(new MarkerOptions().position(
                new LatLng(dLatitude, dLongitude)).title("My Location").icon(BitmapDescriptorFactory.fromBitmap(Utils.getBitmap("pointer_icon.png"))));
        mMap.moveCamera(CameraUpdateFactory.newLatLngZoom(new LatLng(dLatitude, dLongitude), 8));

    }
    else
    {
        Toast.makeText(this, "Unable to fetch the current location", Toast.LENGTH_SHORT).show();
    }

}

Also make sure that the

setMyLocationEnabled

is set to true .

Try and see if this works...

Answer 6

你试过GoogleMap.getMyLocation()吗？

Answer 7

I just found this code snippet simple and functional, try :

public class MainActivity extends ActionBarActivity implements
    ConnectionCallbacks, OnConnectionFailedListener {
...
@Override
public void onConnected(Bundle connectionHint) {
    mLastLocation = LocationServices.FusedLocationApi.getLastLocation(
            mGoogleApiClient);
    if (mLastLocation != null) {
        mLatitudeText.setText(String.valueOf(mLastLocation.getLatitude()));
        mLongitudeText.setText(String.valueOf(mLastLocation.getLongitude()));
    }
}}

here's the link of the tutorial : Getting the Last Known Location

Answer 8

try this

if (ContextCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION)
                == PackageManager.PERMISSION_GRANTED) {
    mMap.setMyLocationEnabled(true);
} else {
    // Show rationale and request permission.
}

Answer 9

Try This

public class MyLocationListener implements LocationListener
{

 @Override

public void onLocationChanged(Location loc)
{

loc.getLatitude();

loc.getLongitude();

String Text = “My current location is: ” +

“Latitud = ” + loc.getLatitude() +

“Longitud = ” + loc.getLongitude();

Toast.makeText( getApplicationContext(),Text,   Toast.LENGTH_SHORT).show();



tvlat.setText(“”+loc.getLatitude());

tvlong.setText(“”+loc.getLongitude());

this.gpsCurrentLocation();

}

Answer 10

It will give the current location.

mMap.setMyLocationEnabled(true);
Location userLocation = mMap.getMyLocation();
        LatLng myLocation = null;
        if (userLocation != null) {
            myLocation = new LatLng(userLocation.getLatitude(),
                    userLocation.getLongitude());
            mMap.animateCamera(CameraUpdateFactory.newLatLngZoom(myLocation,
                    mMap.getMaxZoomLevel()-5));

Answer 11

只有一个条件，我测试它不是null，如果你有足够的时间用户触摸“获取我的位置”图层按钮，那么它将不会获得null值。

Answer 12

the accepted answer works but some of the used methods are now deprecated so I think it is best if I answer this question with updated methods.

this is answer is completely from this guide on google developers

so here is step by step guide:

1. implement all this in your map activity

   MapActivity extends FragmentActivity implements OnMapReadyCallback, GoogleApiClient.OnConnectionFailedListener, GoogleApiClient.ConnectionCallbacks

2. in your onCreate :

    private GoogleMap mMap; private Context context; private TextView txtStartPoint,txtEndPoint; private GoogleApiClient mGoogleApiClient; private Location mLastKnownLocation; private LatLng mDefaultLocation; private CameraPosition mCameraPosition; private boolean mLocationPermissionGranted; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_maps); context = this; mGoogleApiClient = new GoogleApiClient.Builder(this) .enableAutoManage(this /* FragmentActivity */, this /* OnConnectionFailedListener */) .addConnectionCallbacks(this) .addApi(LocationServices.API) .addApi(Places.GEO_DATA_API) .addApi(Places.PLACE_DETECTION_API) .build(); mGoogleApiClient.connect(); } 

3. in your onConnected :

    SupportMapFragment mapFragment = (SupportMapFragment) getSupportFragmentManager() .findFragmentById(map); mapFragment.getMapAsync(this); 

4. in your onMapReady :

    @Override public void onMapReady(GoogleMap googleMap) { mMap = googleMap; // Do other setup activities here too, as described elsewhere in this tutorial. // Turn on the My Location layer and the related control on the map. updateLocationUI(); // Get the current location of the device and set the position of the map. getDeviceLocation(); } 

5. and these two are methods in onMapReady :

    private void updateLocationUI() { if (mMap == null) { return; } if (ContextCompat.checkSelfPermission(this.getApplicationContext(), android.Manifest.permission.ACCESS_FINE_LOCATION) == PackageManager.PERMISSION_GRANTED) { mLocationPermissionGranted = true; } if (mLocationPermissionGranted) { mMap.setMyLocationEnabled(true); mMap.getUiSettings().setMyLocationButtonEnabled(true); } else { mMap.setMyLocationEnabled(false); mMap.getUiSettings().setMyLocationButtonEnabled(false); mLastKnownLocation = null; } } private void getDeviceLocation() { if (ContextCompat.checkSelfPermission(this.getApplicationContext(), android.Manifest.permission.ACCESS_FINE_LOCATION) == PackageManager.PERMISSION_GRANTED) { mLocationPermissionGranted = true; } if (mLocationPermissionGranted) { mLastKnownLocation = LocationServices.FusedLocationApi .getLastLocation(mGoogleApiClient); } // Set the map's camera position to the current location of the device. float DEFAULT_ZOOM = 15; if (mCameraPosition != null) { mMap.moveCamera(CameraUpdateFactory.newCameraPosition(mCameraPosition)); } else if (mLastKnownLocation != null) { mMap.moveCamera(CameraUpdateFactory.newLatLngZoom( new LatLng(mLastKnownLocation.getLatitude(), mLastKnownLocation.getLongitude()), DEFAULT_ZOOM)); } else { Log.d("pouya", "Current location is null. Using defaults."); mMap.moveCamera(CameraUpdateFactory.newLatLngZoom(mDefaultLocation, DEFAULT_ZOOM)); mMap.getUiSettings().setMyLocationButtonEnabled(false); } } 

this is very fast , smooth and effective. hope this helps

Answer 13

I would rather use FusedLocationApi since OnMyLocationChangeListener is deprecated.

First declare these 3 variables:

private LocationRequest  mLocationRequest;
private GoogleApiClient  mGoogleApiClient;
private LocationListener mLocationListener;

Define methods:

private void initGoogleApiClient(Context context)
{
    mGoogleApiClient = new GoogleApiClient.Builder(context).addApi(LocationServices.API).addConnectionCallbacks(new GoogleApiClient.ConnectionCallbacks()
    {
        @Override
        public void onConnected(Bundle bundle)
        {
            mLocationRequest = LocationRequest.create();
            mLocationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);
            mLocationRequest.setInterval(1000);

            setLocationListener();
        }

        @Override
        public void onConnectionSuspended(int i)
        {
            Log.i("LOG_TAG", "onConnectionSuspended");
        }
    }).build();

    if (mGoogleApiClient != null)
        mGoogleApiClient.connect();

}

private void setLocationListener()
{
    mLocationListener = new LocationListener()
    {
        @Override
        public void onLocationChanged(Location location)
        {
            String lat = String.valueOf(location.getLatitude());
            String lon = String.valueOf(location.getLongitude());
            Log.i("LOG_TAG", "Latitude = " + lat + " Longitude = " + lon);
        }
    };

    LocationServices.FusedLocationApi.requestLocationUpdates(mGoogleApiClient, mLocationRequest, mLocationListener);
}

private void removeLocationListener()
{
    LocationServices.FusedLocationApi.removeLocationUpdates(mGoogleApiClient, mLocationListener);
}

• initGoogleApiClient() is used to initialize GoogleApiClient object
• setLocationListener() is used to setup location change listener
• removeLocationListener() is used to remove the listener

Call initGoogleApiClient method to start the code working :) Don't forget to remove the listener ( mLocationListener ) at the end to avoid memory leak issues.