我使用第一个代码开始创建方法isLocationEnabled

 private LocationManager locationManager ;

protected boolean isLocationEnabled(){
        String le = Context.LOCATION_SERVICE;
        locationManager = (LocationManager) getSystemService(le);
        if(!locationManager.isProviderEnabled(LocationManager.NETWORK_PROVIDER)){
            return false;
        } else {
            return true;
        }
    }

和我检查条件，如果true打开地图和false给意图ACTION_LOCATION_SOURCE_SETTINGS

    if (isLocationEnabled()) {
        SupportMapFragment mapFragment = (SupportMapFragment) getSupportFragmentManager()
                .findFragmentById(R.id.map);
        mapFragment.getMapAsync(this);

        locationClient = getFusedLocationProviderClient(this);
        locationClient.getLastLocation()
                .addOnSuccessListener(new OnSuccessListener<Location>() {
                    @Override
                    public void onSuccess(Location location) {
                        // GPS location can be null if GPS is switched off
                        if (location != null) {
                            onLocationChanged(location);

                            Log.e("location", String.valueOf(location.getLongitude()));
                        }
                    }
                })
                .addOnFailureListener(new OnFailureListener() {
                    @Override
                    public void onFailure(@NonNull Exception e) {
                        Log.e("MapDemoActivity", e.toString());
                        e.printStackTrace();
                    }
                });


        startLocationUpdates();

    }
    else {
        new AlertDialog.Builder(this)
                .setTitle("Please activate location")
                .setMessage("Click ok to goto settings else exit.")
                .setPositiveButton(android.R.string.yes, new DialogInterface.OnClickListener() {
                    public void onClick(DialogInterface dialog, int which) {
                        Intent intent = new Intent(Settings.ACTION_LOCATION_SOURCE_SETTINGS);
                        startActivity(intent);
                    }
                })
                .setNegativeButton(android.R.string.no, new DialogInterface.OnClickListener() {
                    public void onClick(DialogInterface dialog, int which) {
                        System.exit(0);
                    }
                })
                .show();
    }

要检查网络提供者，你只需要将传递给isProviderEnabled的字符串更改为LocationManager。NETWORK_PROVIDER如果你检查GPS提供者和网络提供者的返回值-两个false都表示没有位置服务

在Android 8.1或更低的版本上，用户可以开启“省电”模式 >位置>模式>节电。 这种模式只使用WiFi、蓝牙或移动数据，而不是GPS来确定用户的位置。

这就是为什么你必须检查网络提供者是否已启用，locationManager.isProviderEnabled(LocationManager.GPS_PROVIDER)是否不够。

如果你正在使用androidx，这段代码将检查你正在运行的SDK版本，并调用相应的提供商:

public boolean isLocationEnabled(Context context) {
    LocationManager manager = (LocationManager) context.getSystemService(Context.LOCATION_SERVICE);
    return manager != null && LocationManagerCompat.isLocationEnabled(manager);
}

能用最简单的方法做吗

private boolean isLocationEnabled(Context context){
int mode =Settings.Secure.getInt(context.getContentResolver(), Settings.Secure.LOCATION_MODE,
                        Settings.Secure.LOCATION_MODE_OFF);
                final boolean enabled = (mode != android.provider.Settings.Secure.LOCATION_MODE_OFF);
return enabled;
}

You can also use extension function.
------------------------------------

fun Context.isLocationEnabled(): Boolean{
val locationManager = getSystemService(Context.LOCATION_SERVICE) as LocationManager
return LocationManagerCompat.isLocationEnabled(locationManager)}

你可以请求位置更新并同时显示对话框，就像GoogleMaps一样。代码如下:

googleApiClient = new GoogleApiClient.Builder(getActivity())
                .addApi(LocationServices.API)
                .addConnectionCallbacks(this)
                .addOnConnectionFailedListener(this).build();
googleApiClient.connect();

LocationRequest locationRequest = LocationRequest.create();
locationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);
locationRequest.setInterval(30 * 1000);
locationRequest.setFastestInterval(5 * 1000);
LocationSettingsRequest.Builder builder = new LocationSettingsRequest.Builder()
                    .addLocationRequest(locationRequest);

builder.setAlwaysShow(true); //this is the key ingredient

PendingResult<LocationSettingsResult> result = LocationServices.SettingsApi.checkLocationSettings(googleApiClient, builder.build());
result.setResultCallback(new ResultCallback<LocationSettingsResult>() {
    @Override
    public void onResult(LocationSettingsResult result) {
        final Status status = result.getStatus();
        final LocationSettingsStates state = result.getLocationSettingsStates();
        switch (status.getStatusCode()) {
            case LocationSettingsStatusCodes.SUCCESS:
                // All location settings are satisfied. The client can initialize location
                // requests here.
                break;
            case LocationSettingsStatusCodes.RESOLUTION_REQUIRED:
                // Location settings are not satisfied. But could be fixed by showing the user
                // a dialog.
                try {
                    // Show the dialog by calling startResolutionForResult(),
                    // and check the result in onActivityResult().
                    status.startResolutionForResult(getActivity(), 1000);
                } catch (IntentSender.SendIntentException ignored) {}
                break;
            case LocationSettingsStatusCodes.SETTINGS_CHANGE_UNAVAILABLE:
                // Location settings are not satisfied. However, we have no way to fix the
                // settings so we won't show the dialog.
                break;
            }
        }
    });
}

如果需要更多信息，请检查LocationRequest类。