位置管理器对于在Android中的Oreo +设备中启用了GPS的签入始终返回false

Question

当我检查gps是否打开时，

LocationManager在oreo及更高版本的设备中始终返回false，即使我将其打开也仍然返回false。 如何检查oreo和更高版本的设备中的gps是否已打开？

这里是我的代码：

Location manager;

  manager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);

if (!manager.isProviderEnabled(LocationManager.GPS_PROVIDER)) {

           //this if check is always false even when gps is on    
 startActivity(new Intent(Settings.ACTION_LOCATION_SOURCE_SETTINGS));
            }


void onRestart(){
if (!manager.isProviderEnabled(LocationManager.GPS_PROVIDER)) {

         //still returning false when i come back to app from settings screen after turning on gps, but it returns true in android Nougat devices perfectly
            }
}

Answer 1

请使用融合位置客户端
Documentation
它具有高电池效率且易于使用，并且几乎是基于位置的应用程序中的标准。
A youtube tutorial

我的一个应用程序中的一个示例：

@Override
public void onStart() {
    super.onStart();
    fusedLocationProviderClient = LocationServices.getFusedLocationProviderClient(getActivity());
}

@Override
public void onMapReady(GoogleMap googleMap) {
    if (googleMap == null) return;// GUARD
    map = googleMap;
    getDeviceLocationUpdates();
}  



/**
 * Start listening to location changes
 */
private void getDeviceLocationUpdates() {
    if (ActivityCompat.checkSelfPermission(getActivity(), Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(getActivity(), Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
        return;
    }
    locationRequest = new LocationRequest();

    locationRequest.setInterval(Constants.DRIVING_TIME_INTERVAL);
    locationRequest.setFastestInterval(Constants.DRIVING_TIME_INTERVAL);
    locationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);

    fusedLocationProviderClient.requestLocationUpdates(locationRequest, locationCallback, Looper.myLooper());

}  



LocationCallback locationCallback = new LocationCallback() {
    @Override
    public void onLocationResult(LocationResult locationResult) {
        List<Location> locationList = locationResult.getLocations();
        if (locationList.size() > 0) {
            //The last location in the list is the newest
            Location location = locationList.get(locationList.size() - 1);
            Log.i(TAG, "Location: " + location.getLatitude() + " " + location.getLongitude());
            lastLocation = location;

            if (currentLocationMarker != null) {
                currentLocationMarker.remove();
            }

            if (mapPin == null) {
                mapPin = GraphicUtils.resizeImage(getActivity(), Constants.MAP_MARKER_IMAGE_NAME, 100, 100);
            }

            LatLng latLng = new LatLng(location.getLatitude(), location.getLongitude());
            placeCurrentLocationMarker(latLng);

            //move map camera
            map.moveCamera(CameraUpdateFactory.newLatLngZoom(latLng, Constants.DEFAULT_ZOOM));
        }
    }
};  



/**
 * Places a marker with user image on the map on given location
 *
 * @param location GPS Location
 */
private void placeCurrentLocationMarker(LatLng location) {
    Bitmap bitmap = GraphicUtils.createContactBitmap(getActivity(), BitmapFactory.decodeResource(
            getActivity().getResources(),
            Integer.valueOf(((MainActivity) getActivity()).currentUser.getImgUrl())));
    MarkerOptions markerOptions = new MarkerOptions();
    markerOptions.position(location);
    markerOptions.title(getString(R.string.you_are_here));
    markerOptions.icon((bitmap == null) ?
            BitmapDescriptorFactory.fromBitmap(mapPin) :
            BitmapDescriptorFactory.fromBitmap(bitmap));
    currentLocationMarker = map.addMarker(markerOptions);
}

Answer 2

还有另一种可能性与该设备是否为Oreo无关，但是在通过startActivity(new Intent(Settings.ACTION_LOCATION_SOURCE_SETTINGS));重定向的设置活动中，您可能未启用GPS提供商本身。另外，由于您说过 Oreo及以上，我认为您在运行时和清单中都已经授予android.manifest.Permission.ACCESS_FINE_LOCATION的许可。

如果您注意到了，则有3个提供程序：GPS_PROVIDER，NETWORK_PROVIDER和PASSIVE_PROVIDER。您正在使用GPS_PROVIDER来获取您的位置，但是如果未通过设置启用该位置，则该位置可能会返回false。尝试此操作时，可能只选择了网络提供商。

这里是我在说什么的图片（来自HUAWEI-P20 Lite-Android 8.0.0 API 26）：