Question

此代码是有效的，但我有标记的问题，当我运行我的应用程序它确实显示标记，但当我走路改变我的位置，旧位置标记仍然出现在应用程序上，我的最新位置也出现了，怎么能我删除旧的位置标记？

这是我的Activity.java

package stmikbumigoramataram.intro;

import android.Manifest;
import android.content.pm.PackageManager;
import android.location.Address;
import android.location.Geocoder;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;
import android.support.v4.app.ActivityCompat;
import android.support.v4.app.FragmentActivity;
import android.os.Bundle;
import android.util.Log;

import com.google.android.gms.maps.CameraUpdateFactory;
import com.google.android.gms.maps.GoogleMap;
import com.google.android.gms.maps.OnMapReadyCallback;
import com.google.android.gms.maps.SupportMapFragment;
import com.google.android.gms.maps.model.CameraPosition;
import com.google.android.gms.maps.model.LatLng;
import com.google.android.gms.maps.model.Marker;
import com.google.android.gms.maps.model.MarkerOptions;

import java.io.IOException;
import java.util.List;

public class MapsActivity extends FragmentActivity implements OnMapReadyCallback {

private GoogleMap mMap;
private LocationManager locationManager;
private LocationListener locationListener;
Marker currLocationMarker;
@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);

    locationManager = (LocationManager) getSystemService(LOCATION_SERVICE);

    if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
        // TODO: Consider calling
        //    ActivityCompat#requestPermissions
        // here to request the missing permissions, and then overriding
        //   public void onRequestPermissionsResult(int requestCode, String[] permissions,
        //                                          int[] grantResults)
        // to handle the case where the user grants the permission. See the documentation
        // for ActivityCompat#requestPermissions for more details.
        return;
    }

    locationListener = new LocationListener() {
        @Override
        public void onLocationChanged(Location location) {
            double latitude = location.getLatitude();
            double longitude = location.getLongitude();

           if(currLocationMarker != null){
               currLocationMarker.remove();
           }

            LatLng latLng = new LatLng(latitude, longitude);
            Geocoder geocoder = new Geocoder(getApplicationContext());
            try {
                List<Address> addressList = geocoder.getFromLocation(latitude, longitude, 1);
                String str = addressList.get(0).getLocality()+", ";
                str += addressList.get(0).getCountryName();
                currLocationMarker = mMap.addMarker(new MarkerOptions().position(latLng).title(str));

            } catch (IOException e) {
                e.printStackTrace();
            }
            CameraPosition cameraPosition = new CameraPosition.Builder().target(new LatLng(latLng.latitude, latLng.longitude)).zoom(15).build();
            mMap.animateCamera(CameraUpdateFactory.newCameraPosition(cameraPosition));
        }

        @Override
        public void onStatusChanged(String provider, int status, Bundle extras) {

        }

        @Override
        public void onProviderEnabled(String provider) {

        }

        @Override
        public void onProviderDisabled(String provider) {

        }
    };


    locationManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 0, 0, locationListener);
}

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

}

protected void onPause() {
    super.onPause();
    locationManager.removeUpdates(locationListener);
    Log.i("onPause...","paused");
}
}

You can see result of my code here

Answer 1

首先应清除Google地图，然后添加一个新标记，显示为上一个标记删除和新标记添加。

使用此行：

googleMap.clear();

并在Google地图上添加新标记后。

如何在谷歌地图，Android Studio中删除新位置的旧位置标记？

1 个答案: