我的Android应用程序有问题，我无法检索设备的当前位置。从调试应用程序看来，我的LocationListener中的onLocationChange没有被触发。 我已经设置了requestLocationUpdates来处理我的LocationListener，以及输出到onLocationChange中的Log，但我什么也没收到。 我还注意到，当我使用应用程序时，手机顶部栏中没有GPS图标，但如果我切换到谷歌地图应用程序，图标会立即显示... 我现在正在努力解决这个问题，所以任何帮助都会受到赞赏。谢谢。
map fragment.Java:
public class MapFragment extends Fragment implements OnMapReadyCallback {
public static final int MY_PERMISSIONS_REQUEST_LOCATION = 99;
private OnFragmentInteractionListener mListener;
private SupportMapFragment mapFragment;
private GoogleMap googleMap;
LocationManager locationManager;
public MapFragment() {
// Required empty public constructor
}
public static MapFragment newInstance() {
MapFragment fragment = new MapFragment();
Bundle args = new Bundle();
fragment.setArguments(args);
return fragment;
}
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
if (getArguments() != null) {
}
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
return inflater.inflate(R.layout.fragment_map, container, false);
}
@Override
public void onViewCreated(@NonNull View view, @Nullable Bundle savedInstanceState) {
super.onViewCreated(view, savedInstanceState);
mapFragment = (SupportMapFragment) this.getChildFragmentManager().findFragmentById(R.id.map);
mapFragment.onCreate(savedInstanceState);
mapFragment.onResume();
mapFragment.getMapAsync(this);
}
@Override
public void onAttach(Context context) {
super.onAttach(context);
if (context instanceof OnFragmentInteractionListener) {
mListener = (OnFragmentInteractionListener) context;
} else {
throw new RuntimeException(context.toString()
+ " must implement OnFragmentInteractionListener");
}
}
@Override
public void onDetach() {
super.onDetach();
mListener = null;
}
public interface OnFragmentInteractionListener {
void onFragmentInteraction(Uri uri);
}
@Override
public void onMapReady(GoogleMap map) {
googleMap = map;
locationManager = (LocationManager) getActivity().getSystemService(Context.LOCATION_SERVICE);
checkLocationPermission();
}
@Override
public void onRequestPermissionsResult(int requestCode,
String permissions[], int[] grantResults) {
switch (requestCode) {
case MY_PERMISSIONS_REQUEST_LOCATION: {
// If request is cancelled, the result arrays are empty.
if (grantResults.length > 0
&& grantResults[0] == PackageManager.PERMISSION_GRANTED) {
// location-related task you need to do.
if (ContextCompat.checkSelfPermission(getActivity(),
Manifest.permission.ACCESS_FINE_LOCATION)
== PackageManager.PERMISSION_GRANTED) {
//Request location updates:
locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 0, mLocationListener);
locationManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 0, 0, mLocationListener);
}
} else {
// functionality that depends on this permission.
}
return;
}
}
}
private final LocationListener mLocationListener = new LocationListener() {
@Override
public void onLocationChanged(final Location location) {
//your code here
Log.v("LOCATION UPDATE", "IN ON LOCATION CHANGE, lat=" + location.getLatitude() + ", lon=" + location.getLongitude());
/*
LatLng userPosition = new LatLng(location.getLatitude(),location.getLongitude());
googleMap.addMarker(new MarkerOptions()
.position(userPosition)
.icon(BitmapDescriptorFactory.fromResource(R.drawable.ic_pin_fill))
.title("Test Pin"));*/
}
@Override
public void onStatusChanged(String provider, int status, Bundle extras) {
}
@Override
public void onProviderEnabled(String provider) {
}
@Override
public void onProviderDisabled(String provider) {
}
};
public boolean checkLocationPermission() {
if (ContextCompat.checkSelfPermission(getActivity(),
Manifest.permission.ACCESS_FINE_LOCATION)
!= PackageManager.PERMISSION_GRANTED) {
// Should we show an explanation?
if (ActivityCompat.shouldShowRequestPermissionRationale(getActivity(),
Manifest.permission.ACCESS_FINE_LOCATION)) {
//dialog to ask for permission
new AlertDialog.Builder(getActivity())
.setTitle("Permission")
.setMessage("Need permission")
.setPositiveButton("OK", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialogInterface, int i) {
//Prompt the user once explanation has been shown
ActivityCompat.requestPermissions(getActivity(),
new String[]{Manifest.permission.ACCESS_FINE_LOCATION},
MY_PERMISSIONS_REQUEST_LOCATION);
}
})
.create()
.show();
}
else {
ActivityCompat.requestPermissions(getActivity(),
new String[]{Manifest.permission.ACCESS_FINE_LOCATION},
MY_PERMISSIONS_REQUEST_LOCATION);
locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 0, mLocationListener);
locationManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 0, 0, mLocationListener);
}
return false;
} else {
return true;
}
}
}
不确定是否相关但是fragment_map.xml
<fragment xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:map="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/map"
android:name="com.google.android.gms.maps.SupportMapFragment"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MapFragment" />
你确定locationManager.requestLocationUpdates()正在执行吗？基于此代码，如果在启动时已经授予ACCESS_FINE_LOCATION，则checkLocationPermission()将返回true，并且没有任何内容调用requestLocationUpdates()。