Android LocationManager.getLastKnownLocation（）在Android 4.1.1上返回null

Question

我正在开发Android应用程序。我陷入了困境。 getLastKnownLocation(provider)为Android版本4.1.1返回null，而对于其他版本则可以。提供商已启用，其余的都可以。我不知道问题出在哪里。这是代码。

LocationManager locationManager = (LocationManager) getSystemService(LOCATION_SERVICE);
    Criteria criteria = new Criteria();
    String provider = locationManager.getBestProvider(criteria, true);
    location = locationManager.getLastKnownLocation(provider);
    double latitude = location.getLatitude();
    double longitude = location.getLongitude();
    LatLng latLng = new LatLng(latitude, longitude);
    mMap.clear();
    System.out.println("Current Location = "+latLng); 

Answer 1

如果禁用了提供程序，

locationManager.getLastKnownLocation将返回null，这里是文档

  

http://developer.android.com/reference/android/location/LocationManager.html#getLastKnownLocation(java.lang.String)

Answer 2

试试这个为我工作......

  mGoogleMap.setOnMyLocationButtonClickListener(new OnMyLocationButtonClickListener() {

                    @Override
                    public boolean onMyLocationButtonClick()
                        {

                            Location myLocation = mGoogleMap.getMyLocation();
                            onLocationChanged(myLocation);
                            return false;
                        }
                });