Android Studio Google Maps 无法获取 latlng 或找不到蓝点

Question

我正在尝试在我的应用上使用 Google 地图。到目前为止，我能够将地图加载到 SupportMapFragment 上，该 SupportMapFragment 作为片段调用到我的 MainActivity 上。但是，尽管启用了位置，但我看不到蓝点。我也无法获得显示在日志中的纬度或经度。有人可以帮我弄这个吗？我很迷茫。可能是我设置的权限吗？我还在清单中添加了必要的权限。 这是我的代码

public class MapFragment extends SupportMapFragment implements LocationListener,OnMapReadyCallback, GoogleApiClient.ConnectionCallbacks, GoogleApiClient.OnConnectionFailedListener{

    private GoogleMap googleMap;
    private GoogleApiClient googleApiClient;
    private LocationRequest locationRequest;
    public static final int MY_PERMISSIONS_REQUEST_LOCATION = 99;
    Location location;
    Marker locationMarker;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
    }

    protected synchronized void buildGoogleAPIClient(){
        googleApiClient = new GoogleApiClient.Builder(getActivity())
                .addConnectionCallbacks(this)
                .addOnConnectionFailedListener(this)
                .addApi(LocationServices.API)
                .build();
        googleApiClient.connect();
    }

    @Override
    public void onLocationChanged(Location location) {
        LatLng currentLocation = new LatLng(location.getLatitude(),location.getLongitude());
        Double latitude = currentLocation.latitude;
        Double longitude = currentLocation.longitude;
        this.location = location;
        if(locationMarker!=null){
            locationMarker.remove();
        }
        MarkerOptions markerOptions = new MarkerOptions();
        markerOptions.position(currentLocation);
        markerOptions.title("Current Position");
        markerOptions.icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_AZURE));
        locationMarker = googleMap.addMarker(markerOptions);

        if(googleApiClient!=null){
            LocationServices.FusedLocationApi.removeLocationUpdates(googleApiClient,this);
        }
    }

    @Override
    public void onMapReady(GoogleMap googleMap) {
        this.googleMap = googleMap;
        if(Build.VERSION.SDK_INT >= Build.VERSION_CODES.M){
            if(ContextCompat.checkSelfPermission(getActivity(), Manifest.permission.ACCESS_FINE_LOCATION)== PackageManager.PERMISSION_GRANTED){
                buildGoogleAPIClient();
                this.googleMap.setMyLocationEnabled(true);
            }else{
                checkLocationPermission();
            }
        }else{
            buildGoogleAPIClient();
            this.googleMap.setMyLocationEnabled(true);
        }
    }

    @Override
    public void onPause() {
        super.onPause();
        if(googleApiClient!=null){
            LocationServices.FusedLocationApi.removeLocationUpdates(googleApiClient,this);
        }
    }

    @Override
    public void onConnected(@Nullable Bundle bundle) {
        locationRequest = new LocationRequest();
        locationRequest.setInterval(1000);
        locationRequest.setFastestInterval(1000);
        locationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);
        if(ContextCompat.checkSelfPermission(getActivity(),Manifest.permission.ACCESS_FINE_LOCATION)==PackageManager.PERMISSION_GRANTED){
            LocationServices.FusedLocationApi.requestLocationUpdates(googleApiClient,locationRequest,this);
        }
    }

    private void checkLocationPermission(){
        if(ContextCompat.checkSelfPermission(getActivity(),Manifest.permission.ACCESS_FINE_LOCATION)!=PackageManager.PERMISSION_GRANTED){
            //Ask for permission again once the user sees the explanation
            if(ActivityCompat.shouldShowRequestPermissionRationale(getActivity(),Manifest.permission.ACCESS_FINE_LOCATION)){
                new AlertDialog.Builder(getActivity())
                        .setTitle("Location Permission required")
                        .setMessage("This app requires location permissions in order to function")
                        .setPositiveButton("Allow", new DialogInterface.OnClickListener() {
                            @Override
                            public void onClick(DialogInterface dialog, int which) {
                                ActivityCompat.requestPermissions(getActivity(),new String[]{Manifest.permission.ACCESS_FINE_LOCATION},MY_PERMISSIONS_REQUEST_LOCATION);
                            }
                        })
                        .create()
                        .show();
            }else{
                //No explanation required. Just request for permissions
                ActivityCompat.requestPermissions(getActivity(),new String[]{Manifest.permission.ACCESS_FINE_LOCATION},MY_PERMISSIONS_REQUEST_LOCATION);
            }
        }
    }

    @Override
    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
        super.onRequestPermissionsResult(requestCode, permissions, grantResults);
        switch (requestCode){
            case MY_PERMISSIONS_REQUEST_LOCATION: {
                if(grantResults.length>0 && grantResults[0]==PackageManager.PERMISSION_GRANTED){
                    if(googleApiClient==null){
                        buildGoogleAPIClient();
                    }
                    if(ContextCompat.checkSelfPermission(getActivity(), Manifest.permission.ACCESS_FINE_LOCATION)== PackageManager.PERMISSION_GRANTED){
                        this.googleMap.setMyLocationEnabled(true);
                    }
                }else{
                    Toast.makeText(getActivity(),"Permission denied",Toast.LENGTH_LONG).show();
                }
                return;
            }
        }
    }

    @Override
    public void onConnectionSuspended(int i) {

    }

    @Override
    public void onConnectionFailed(@NonNull ConnectionResult connectionResult) {

    }

希望有人可以帮助我。谢谢

Answer 1

记得添加以下权限：

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

Answer 2

在您显示的代码中，您永远不会在 SupportMapFragment 上调用 getMapAsync，所以基本上您只是在显示地图。

将getMapAsync 添加到您的onCreate：

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    getMapAsync(this);
}