Question

我试图在地图活动中标记当前用户位置，但是LocationServices.FusedLocationApi.getLastLocation的调用始终返回null

public class MapsActivity extends AppCompatActivity implements OnMapReadyCallback,GoogleApiClient.ConnectionCallbacks,GoogleApiClient.OnConnectionFailedListener {

private GoogleMap mMap;
private GoogleApiClient mGoogleApiClient=null;
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_maps);
    // Obtain the SupportMapFragment and get notified when the map is ready to be used.
    SupportMapFragment mapFragment = (SupportMapFragment) getSupportFragmentManager()
            .findFragmentById(R.id.map);
    mapFragment.getMapAsync(this);

    if (mGoogleApiClient == null) {
        mGoogleApiClient = new GoogleApiClient.Builder(this)
                .addConnectionCallbacks(this)
                .addOnConnectionFailedListener(this)
                .addApi(LocationServices.API)
                .build();
    }
    mGoogleApiClient.connect();

}


@Override
public void onConnectionFailed(ConnectionResult connectionResult) {

}

@Override
public void onConnectionSuspended(int i) {

}

@Override
public void onConnected(Bundle bundle) {

}

@Override
protected void onStart() {
    if(mGoogleApiClient.isConnected())
        Toast.makeText(this,"Client Connect",Toast.LENGTH_SHORT).show();
    else
        mGoogleApiClient.connect();
    super.onStart();
}


@Override
public void onMapReady(GoogleMap googleMap) {
    mMap = googleMap;

    if (ContextCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION)
            == PackageManager.PERMISSION_GRANTED) {
        mLastLocation = LocationServices.FusedLocationApi.getLastLocation(
                mGoogleApiClient);
        LatLng myLocation = null;
        if(mLastLocation!=null) {
            myLocation = new LatLng(mLastLocation.getLatitude(),
                    mLastLocation.getLongitude());
            mMap.animateCamera(CameraUpdateFactory.newLatLngZoom(myLocation,
                    mMap.getMaxZoomLevel() - 5));
        }
    } else {
        // Show rationale and request permission.
    }


}
 }

此外，我已在清单文件中添加了权限

在检查mGoogleApiClient的连接时，它始终没有连接

Answer 1

您需要为位置事件注册一个监听器，并开始在很短的时间内收听所收到的几个位置，并比较它们的准确性，来源等，以确定哪个是最佳位置，然后使用该位置。

阅读Location strategies google文档，这非常有用，并提供了获取准确位置所需操作的代码示例。

同时将此权限添加到清单：

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

LocationServices.FusedLocationApi.getLastLocation始终为空

1 个答案: