Question

我正在使用Nexus 6p和Android 7.1.2。我将设备位置精度设置为HIGH_ACCURACY。在我的代码中，我使用FusedLocation API为位置更新提供了后台服务。如您所见，我还将位置请求优先级设置为HIGH_ACCURACY。现在我已经测试了它，当设备在我的桌面上没有任何动作时，大多数时候我都有相同的LAT / LONG值，有时我看到LAT / LONG值的微小变化，即使设备不是不动了。所以我使用getAccuracy方法打印了位置精度。文档说如果getAccuracy方法返回值> = 68，那么这意味着设备（用户）很可能在此位置。所以我尝试使用此方法（下面代码的另一个版本）并检查getAccuracy是否返回值＆gt; = 68然后打印位置详细信息。你猜怎么着？它没那么帮助..

我接下来尝试的是旋转设备，我看到当设备处于landsacpe模式时背对着我，位置lat / long被改变了（即使我没有去任何地方）和准确性增加了，在某些情况下达到了180.

所以我不明白这一点：

为什么有时设备的纬度/经度值会有所不同，即使设备躺在桌面上并且不移动？

轮换如何影响定位精度？！

我的代码：

 public class LocationUpdateService extends Service implements
        GoogleApiClient.ConnectionCallbacks, 
        GoogleApiClient.OnConnectionFailedListener,
        LocationListener
{

    private GoogleApiClient googleApiClient;
    private LocationRequest locationRequest;

    private boolean playsServiceAvailable;

    private String TAG = getClass().getSimpleName();

    @Override
    public void onCreate()
    {
        Log.d(TAG,"onCreate");
        super.onCreate();

        initRequestLocation();

        playsServiceAvailable = checkPlayServicesConnection();

        setupLocationApiClient();
    }

    @Nullable
    @Override
    public IBinder onBind(Intent intent)
    {
        return null;
    }

    @Override
    public int onStartCommand(Intent intent, int flags, int startId)
    {
        Log.d(TAG, "onStartCommand");
        super.onStartCommand(intent,flags,startId);

        if (!playsServiceAvailable || googleApiClient.isConnected())            
        {

            return START_STICKY;
        }

        setupLocationApiClient();

        if (!googleApiClient.isConnected() || !googleApiClient.isConnecting())
        {
            Log.d(TAG, "onStartCommand: googleApiclient.connect()");
            googleApiClient.connect();
        }

        return START_STICKY;
    }

    @Override
    public void onDestroy()
    {
        Log.d(TAG, "onDestroy");

        if (this.playsServiceAvailable && this.googleApiClient != null)
        {
            this.googleApiClient.unregisterConnectionCallbacks(this);
            this.googleApiClient.unregisterConnectionFailedListener(this);
            this.googleApiClient.disconnect();
            this.googleApiClient = null;
        }

        super.onDestroy();
    }

    @Override
    public void onConnected(@Nullable Bundle bundle)
    {
        try
        {
            LocationServices.FusedLocationApi.requestLocationUpdates(this.googleApiClient, locationRequest, this);
        }
        catch (SecurityException e)
        {
            e.printStackTrace();
        }
    }

    @Override
    public void onConnectionSuspended(int i)
    {
        googleApiClient = null;
    }

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

    @Override
    public void onLocationChanged(Location currentLocation)
    {
        Log.d(TAG, "onLocationChanged:\n\t\t\t" +
                "CurrentLocation:\n\t\t\t\t" +
                "ACCURACY: " + currentLocation.getAccuracy() + "\n\t\t\t\t" +
                "LAT: " + currentLocation.getLatitude() + "\n\t\t\t\t" +
                "LONG: " + currentLocation.getLongitude() + "\n\t\t\t\t" +
                "TIME: " + currentLocation.getTime());

    }

    private boolean checkPlayServicesConnection ()
    {
        int resultCode = GoogleApiAvailability.getInstance().isGooglePlayServicesAvailable(context);

        if (resultCode != ConnectionResult.SUCCESS)
        {
            return false;
        }
        return true;
    }

    private void initRequestLocation()
    {
        locationRequest = LocationRequest.create();
        locationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY)
                .setInterval(5000)
                .setFastestInterval(1000);
    }

    private void setupLocationApiClient()
    {
        Log.d(TAG,"setupLocationApiClient");
        if (googleApiClient == null)
            initGoogleApiClient();
    }

    private synchronized void initGoogleApiClient()
    {
        Log.d(TAG,"initGoogleApiClient");
        googleApiClient = new GoogleApiClient.Builder(this)
                .addApi(LocationServices.API)
                .addOnConnectionFailedListener(this)
                .addConnectionCallbacks(this)
                .build();
    }
}

Answer 1

这是GPS In-accuracy，这不是设备的问题。它试图获取确切的位置，这就是为什么它在这里移动尝试提高gps的准确性。尝试设置最小的位移和间隔，以获得更准确的结果。

 mLocationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);
 mLocationRequest.setSmallestDisplacement(27);//27 meter
 mLocationRequest.setInterval(5000); // Update location every 5 seconds
 LocationServices.FusedLocationApi.requestLocationUpdates(mGoogleApiClient, 
 mLocationRequest, this);

出错位置lat / long

1 个答案: