java - 当我将标记当前位置拖到另一个位置时，如何更新位置？

Question

当我将我的位置指针拖到另一个地方时更新位置。并且它显示在标记标题上，例如当前位置。目前，它显示标记标题，但显示标记放置的位置。

public class MapActivity extends FragmentActivity implements OnMapReadyCallback,GoogleApiClient.ConnectionCallbacks,GoogleApiClient.OnConnectionFailedListener,
    LocationListener, GoogleMap.OnMarkerClickListener, GoogleMap.OnMarkerDragListener {

public static final int MY_PERMISSIONS_REQUEST_LOCATION = 99;
TextView add;
Button button;
GoogleApiClient mGoogleApiClient;
Location mLastLocation;
Marker mCurrLocationMarker;
LocationRequest mLocationRequest;
String getbuildingname,locality,subLocality,current_state,current_country,postal_code;
double longitude,latitude;
double last_longitude,last_latitude;
private GoogleMap mMap;
String addrs;
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_map);
    button = findViewById(R.id.button);
    add = (TextView)findViewById(R.id.current_location);
    if (android.os.Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
        checkLocationPermission();
    }
    SupportMapFragment mapFragment = (SupportMapFragment)
            getSupportFragmentManager()
                    .findFragmentById(R.id.map);

    mapFragment.getMapAsync(this);
    add_location();


}
// Map ready method
@Override
public void onMapReady(GoogleMap googleMap) {
    mMap = googleMap;
    mMap.setMapType(GoogleMap.MAP_TYPE_HYBRID);
    mMap.getUiSettings().setZoomControlsEnabled(true);
    mMap.getUiSettings().setZoomGesturesEnabled(true);
    mMap.getUiSettings().setCompassEnabled(true);
    //Initialize Google Play Services
    if (android.os.Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
        if (ContextCompat.checkSelfPermission(this,
                Manifest.permission.ACCESS_FINE_LOCATION)
                == PackageManager.PERMISSION_GRANTED) {
            buildGoogleApiClient();
            mMap.setMyLocationEnabled(true);

        }
    } else {
        buildGoogleApiClient();
        mMap.setMyLocationEnabled(true);
    }
    mMap.setOnMarkerClickListener(this);
    mMap.setOnMarkerDragListener(this);
}
protected synchronized void buildGoogleApiClient() {
    mGoogleApiClient = new GoogleApiClient.Builder(this)
            .addConnectionCallbacks(MapActivity.this)
            .addOnConnectionFailedListener(this)
            .addApi(LocationServices.API)
            .build();
    mGoogleApiClient.connect();
}
@Override
public void onConnected(Bundle bundle) {
    mLocationRequest = new LocationRequest();
    mLocationRequest.setInterval(1000);
    mLocationRequest.setFastestInterval(1000);
    mLocationRequest.setPriority(LocationRequest.PRIORITY_BALANCED_POWER_ACCURACY);
    if (ContextCompat.checkSelfPermission(this,
            Manifest.permission.ACCESS_FINE_LOCATION)
            == PackageManager.PERMISSION_GRANTED) {
        LocationServices.FusedLocationApi.requestLocationUpdates(mGoogleApiClient,
                mLocationRequest, this);
    }
}
@Override
public void onConnectionSuspended(int i) {
}
@Override
public void onLocationChanged(Location location) {
    mLastLocation = location;
    if (mCurrLocationMarker != null) {
        mCurrLocationMarker.remove();
    }
     //Showing Current Location Marker on Map
    LatLng latLng = new LatLng(location.getLatitude(), location.getLongitude());
    MarkerOptions markerOptions = new MarkerOptions();
    markerOptions.position(latLng);
    LocationManager locationManager = (LocationManager)
            getSystemService(Context.LOCATION_SERVICE);
    assert locationManager != null;
    String provider = locationManager.getBestProvider(new Criteria(), true);
    if (ActivityCompat.checkSelfPermission(this,
            Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED &&
            ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION)
                    != PackageManager.PERMISSION_GRANTED) {
        return;
    }
    assert provider != null;
    Location locations = locationManager.getLastKnownLocation(provider);
    List<String> providerList = locationManager.getAllProviders();
    if (null != locations && providerList.size() > 0) {
        longitude = locations.getLongitude();
        latitude = locations.getLatitude();

        // Geo Coder access location via lat and long
        Geocoder geocoder = new Geocoder(getApplicationContext(),
                Locale.getDefault());
        try {
            List<Address> listAddresses = geocoder.getFromLocation(latitude,
                    longitude, 1);
            if (null != listAddresses && listAddresses.size() > 0) {
                getbuildingname = listAddresses.get(0).getAddressLine(0);
                locality = listAddresses.get(0).getLocality(); 
                subLocality = listAddresses.get(0).getSubLocality();  
                current_state = listAddresses.get(0).getAdminArea();  
                current_country = listAddresses.get(0).getCountryName();
                postal_code = listAddresses.get(0).getPostalCode();  
                markerOptions.title(""+latLng+","+subLocality+"," + locality + "," +
                        current_state + "," + current_country + "," + postal_code);

            }
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
    markerOptions.icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_CYAN));
    mCurrLocationMarker = mMap.addMarker(markerOptions);
    mMap.moveCamera(CameraUpdateFactory.newLatLng(latLng));
    mMap.animateCamera(CameraUpdateFactory.zoomTo(18));
    if (mGoogleApiClient != null) {
        LocationServices.FusedLocationApi.removeLocationUpdates(mGoogleApiClient,
                this);
    }
}
@Override
public void onConnectionFailed(@NonNull ConnectionResult connectionResult) {
}
public boolean checkLocationPermission() {
    if (ContextCompat.checkSelfPermission(this,
            Manifest.permission.ACCESS_FINE_LOCATION)
            != PackageManager.PERMISSION_GRANTED) {

        if (ActivityCompat.shouldShowRequestPermissionRationale(this,
                Manifest.permission.ACCESS_FINE_LOCATION)) {
            ActivityCompat.requestPermissions(this,
                    new String[]{Manifest.permission.ACCESS_FINE_LOCATION},
                    MY_PERMISSIONS_REQUEST_LOCATION);
        } else {
            ActivityCompat.requestPermissions(this,
                    new String[]{Manifest.permission.ACCESS_FINE_LOCATION},
                    MY_PERMISSIONS_REQUEST_LOCATION);
        }
        return false;
    } else {
        return true;
    }
}
@Override
public void onRequestPermissionsResult(int requestCode,
                                       String permissions[], int[] grantResults) {
    if (requestCode == MY_PERMISSIONS_REQUEST_LOCATION) {
        if (grantResults.length > 0
                && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
            if (ContextCompat.checkSelfPermission(this,
                    Manifest.permission.ACCESS_FINE_LOCATION)
                    == PackageManager.PERMISSION_GRANTED) {
                if (mGoogleApiClient == null) {
                    buildGoogleApiClient();
                }
                mMap.setMyLocationEnabled(true);
            }
        } else {
            Toast.makeText(this, "permission denied",
                    Toast.LENGTH_LONG).show();
        }
        return;
    }
}
// Click Listener with data insertion
private void add_location(){

    button.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {

            String lat = String.valueOf(latitude);
            String lng = String.valueOf(longitude);
            addrs = "Latitude - "+lat+" , "+"Longitude - "+lng+"\nAddress - "+getbuildingname;
            add.setText(addrs);
            add.setTypeface(null, Typeface.BOLD);
        }
    });
}

// New Methods
@Override
public boolean onMarkerClick(Marker marker) {
    marker.setDraggable(true);
    return false;
}

@Override
public void onMarkerDragStart(Marker marker) {

}

@Override
public void onMarkerDrag(Marker marker) {

}

@Override
public void onMarkerDragEnd(Marker marker) {
    last_latitude = marker.getPosition().latitude;
    last_longitude = marker.getPosition().longitude;

}

我可以获得我的当前位置并可以拖动标记。

没有错误，但我不知道如何更新位置？

Answer 1

您应该在 onMarkerDrag 方法中调用 marker.getPosition() 以获取标记在拖动时的当前位置。 (我明白这是你想做的，但如果不对请指正)。

作为引用，Google 关于 marker drag events 的文档状态:

You can use an OnMarkerDragListener to listen for drag events on a marker. To set this listener on the map, call GoogleMap.setOnMarkerDragListener.

When a marker is dragged, onMarkerDragStart(Marker) is called initially. While the marker is being dragged, onMarkerDrag(Marker) is called constantly. At the end of the drag onMarkerDragEnd(Marker) is called. You can get the position of the marker at any time by calling Marker.getPosition().

希望对你有帮助。