Android：Google Fused Location 在位置关闭时不起作用

Question

getLastLocation() returns NULL 而 phone location 在我的 6.0 Nexus 7 平板电脑上关闭，但在另一台设备上它可以在没有 GPS 的情况下工作。为什么会这样，有什么办法可以解决吗？我想关闭 GPS，只使用网络获取位置。

下面是我用来获取位置的class：

public class GPSCenter {
public static GoogleApiClient mGoogleApiClient;
public static Location mLastLocation;
private static Context mContext;

static GoogleApiClient.ConnectionCallbacks ccb = new GoogleApiClient.ConnectionCallbacks() {

    @Override
    public void onConnectionSuspended(int arg0) {
    }

    @Override
    public void onConnected(Bundle arg0) {

        if (ActivityCompat.checkSelfPermission(mContext, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
            return;
        }

        LocationRequest mLocationRequest = LocationRequest.create();
        mLocationRequest.setPriority(LocationRequest.PRIORITY_NO_POWER);

        mLastLocation = LocationServices.FusedLocationApi.getLastLocation(mGoogleApiClient);
    }
};
static GoogleApiClient.OnConnectionFailedListener odfl = new GoogleApiClient.OnConnectionFailedListener() {
    @Override
    public void onConnectionFailed(ConnectionResult arg0) {
    }
};

public static synchronized void buildGoogleApiClient(Context c) {
    try {

        mContext = c;
        mGoogleApiClient = new GoogleApiClient.Builder(c)
                .addConnectionCallbacks(ccb)
                .addOnConnectionFailedListener(odfl)
                .addApi(LocationServices.API)
                .build();

        mGoogleApiClient.connect();
    } catch (Exception ex) {
        Log.i("location", "error " + ex.toString());
        ex.printStackTrace();
    }
}

public static double getLatitude(Context c) {
    try {
        return mLastLocation.getLatitude();
    } catch (Exception ex) {
        return 0.0;
    }
}

public static double getLongitude(Context c) {
    try {
        return mLastLocation.getLongitude();
    } catch (Exception ex) {
        return 0.0;
    }
}
}

Answer 1

Through Google Api i think it's not possible. for that you need to use some api for ip geolocation or you may use MNC-Mobile network location or MCC-Mobile country code through this you can get. It may help you.

Answer 2

下面解释不返回任何位置值部分：
LocationRequest.PRIORITY_NO_POWER:

No locations will be returned unless a different client has requested location updates in which case this request will act as a passive listener to those locations.

对于FusedLocationProvider、

no explicitly unique source is specified anywhere within documentation.

因此，为了在不启用 GPS 的情况下获取位置，您可以相信 PRIORITY_BALANCED_POWER_ACCURACY. From what i have observed, only PRIORITY_HIGH_ACCURACY 以强制方式使用 GPS。

平板电脑可能只有 wifi 或没有 sim 卡，这与其他设备不同，排除了其他应用程序获取位置的情况——可能使用网络。

Answer 3

这不是因为 GPS 问题，而是 Location Settings 尚未在设备中启用，它位于您的设备设置>Google>服务>位置或设置>隐私和安全> 位置，或只是设置> 位置。我很困惑，因为在某些设备中，下拉状态栏显示 GPS 启用按钮，有些显示位置启用按钮。有一种方法可以自动启用位置设置（无需将用户导航到设备设置），它解决了我的问题，希望对您有所帮助：

连接 GoogleApiClient 后，进行位置设置检查，如下所示：

public static GoogleApiClient mGoogleApiClient;
private static PendingResult<LocationSettingsResult> result;
private static LocationSettingsRequest.Builder builder;
public static Location mLastLocation;
public static boolean isLocationON = false;

public static synchronized void buildGoogleApiClient(Activity a, Context c) {

    try {

        mActivity = a;
        mContext = c;
        mGoogleApiClient = new GoogleApiClient.Builder(c)
                .addConnectionCallbacks(ccb)
                .addOnConnectionFailedListener(odfl)
                .addApi(LocationServices.API)
                .build();

        builder = new LocationSettingsRequest.Builder()
                .addLocationRequest(locationRequest);
        builder.setAlwaysShow(true);

        mGoogleApiClient.connect();

    } catch (Exception ex) {
        ex.printStackTrace();
    }
}

private static GoogleApiClient.ConnectionCallbacks ccb = new GoogleApiClient.ConnectionCallbacks() {

    @Override
    public void onConnected(Bundle arg0) {
        checkLocationSettings();
    }

    @Override
    public void onConnectionSuspended(int arg0) {
    }
};

private static void checkLocationSettings() {

    result = LocationServices.SettingsApi.checkLocationSettings(mGoogleApiClient, builder.build());

    result.setResultCallback(new ResultCallback<LocationSettingsResult>() {

        @Override
        public void onResult(@NonNull LocationSettingsResult locationSettingsResult) {
            final Status status = locationSettingsResult.getStatus();
            switch (status.getStatusCode()) {
                case LocationSettingsStatusCodes.SUCCESS:

                    isLocationON = true;

                    if (ActivityCompat.checkSelfPermission(mContext, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
                        return;
                    }
                    mLastLocation = LocationServices.FusedLocationApi.getLastLocation(mGoogleApiClient);

                    if (mLocationSettingsListener != null) {
                        mLocationSettingsListener.onLocationON();
                    }

                    break;

                case LocationSettingsStatusCodes.RESOLUTION_REQUIRED:

                    isLocationON = false;

                    try {
                        // This line will check the result and prompt a dialog if the device location settings is not enabled
                        status.startResolutionForResult(mActivity, REQUEST_CHECK_SETTINGS);

                    } catch (IntentSender.SendIntentException e) {
                    }
                    break;

                case LocationSettingsStatusCodes.SETTINGS_CHANGE_UNAVAILABLE:
                    isLocationON = false;
                    // Location settings are unavailable so not possible to show any dialog now
                    if (mLocationSettingsListener != null) {
                        mLocationSettingsListener.onLocationError();
                    }
                    break;
            }
        }
    });
}

Answer 4

您必须在模拟器中将位置精度设置为“仅设备”。模拟器中的 FusedLocationProviderApi 无法使用高精度或省电模式。

Android：Google Fused Location 在位置关闭时不起作用

Android: Google Fused Location doesn't work while location is turned off

android

location

nexus-7

fusedlocationproviderapi

android-fusedlocation