从Firestore云数据库在地图视图上绘制多个标记

Question

我已经存储了经度&Firestore Collection中的纬度，并使用Marker I将其显示在地图上。但是在地图上仅显示一个标记。我想使用存储的经度和经度在地图上显示多个标记；Firestore Collection中的纬度。

这是我的java代码

package part.time.job.v2;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import androidx.annotation.NonNull;
import androidx.fragment.app.Fragment;
import androidx.fragment.app.FragmentTransaction;
import com.google.android.gms.maps.CameraUpdateFactory;
import com.google.android.gms.maps.GoogleMap;
import com.google.android.gms.maps.MapView;
import com.google.android.gms.maps.OnMapReadyCallback;
import com.google.android.gms.maps.model.LatLng;
import com.google.android.gms.maps.model.MarkerOptions;
import com.google.android.gms.tasks.OnSuccessListener;
import com.google.android.material.bottomnavigation.BottomNavigationView;
import com.google.firebase.firestore.CollectionReference;
import com.google.firebase.firestore.FirebaseFirestore;
import com.google.firebase.firestore.QueryDocumentSnapshot;
import com.google.firebase.firestore.QuerySnapshot;
public class LabourFragment extends Fragment implements OnMapReadyCallback {
GoogleMap mGoogleMap;
MapView mMapview;
public LabourFragment() {
// Required empty public constructor
}

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
View view = inflater.inflate(R.layout.fragment_labour, container, false);
return view;
}
@Override
public void onViewCreated(@NonNull View view, Bundle savedInstanceState) {
super.onViewCreated(view, savedInstanceState);
mMapview = (MapView) view.findViewById(R.id.mapView);
if (mMapview != null) {
mMapview.onCreate(null);
mMapview.onResume();
mMapview.getMapAsync(this);
}
}
@Override
public void onMapReady(final GoogleMap googleMap) {
FirebaseFirestore mDatabase = FirebaseFirestore.getInstance();
CollectionReference mOrderRef = mDatabase.collection("Job Post1");
mOrderRef.get().addOnSuccessListener(new OnSuccessListener < QuerySnapshot > () {
@Override
public void onSuccess(QuerySnapshot queryDocumentSnapshots) {
for (QueryDocumentSnapshot documentSnapshot: queryDocumentSnapshots) {
if (documentSnapshot.contains("lat") && documentSnapshot.contains("lon")) {
String lat = (String) documentSnapshot.get("lat");
String lon = (String) documentSnapshot.get("lon");
String title = (String) documentSnapshot.get("title");
if (lat != null && lon != null && !lat.isEmpty() && !lon.isEmpty()) {
double latitude = Double.parseDouble(lat.trim());
double longitude = Double.parseDouble(lon.trim());
LatLng latLng = new LatLng(latitude, longitude);
googleMap.addMarker(new MarkerOptions().position(latLng).title(title));
googleMap.moveCamera(CameraUpdateFactory.newLatLng(latLng));

}
}
}
}
});
}
}

这里我使用的是mapView和firebase Firestore云数据库

Answer 1

用于多个标记

if(lat != null && lon != null && !lat.isEmpty() && !lon.isEmpty()) {
double latitude = Double.parseDouble(lat.trim());
double longitude = Double.parseDouble(lon.trim());
addmarker(latitude,longitude );
}
private void addmarker(Float latitude, Float longitude) {
mgoogleMap.addMarker(new MarkerOptions().position(new LatLng(latitude, longitude)));
mgoogleMap.animateCamera(CameraUpdateFactory.newLatLngZoom(new LatLng(latitude, longitude), 12.0f));
}