将来自 Firebase 的数据显示到自定义信息中 Window

Question

我试图在从数据库中检索到位置数据后，将来自 Firebase 的一些用户详细信息显示到自定义地图标记中，但我不知道我是否应该实施 FirebaseRecyclerAdapter 或普通的。我应该怎么做？

我试图至少检索用户的姓名、紧急情况类型和警报级别，并在单击标记时显示在信息 Window 上：

{
  "Blocked Users" : {
    "RCX2HZXIwlSmMHFgDytf1DgZBgi2" : 0,
    "vqP3H4maEfQxCBHEWqsH9q4O1M52" : 0
  },
  "User Location" : {
    "RCX2HZXIwlSmMHFgDytf1DgZBgi2" : {
      "latitude" : 15.506605,
      "longitude" : 120.86838
    },
    "vqP3H4maEfQxCBHEWqsH9q4O1M52" : {
      "latitude" : 37.3259633,
      "longitude" : -121.898475
    }
  },
  "Users" : {
    "RCX2HZXIwlSmMHFgDytf1DgZBgi2" : {
      "Alert Level" : "High",
      "Emergency Type" : "Natural Disaster",
      "address" : "Lapaz Tarlac",
      "emergencyNum" : "0981232387346",
      "name" : "Rafael Campos",
      "phoneNum" : "0981233445675"
    },
    "vqP3H4maEfQxCBHEWqsH9q4O1M52" : {
      "Alert Level" : "High",
      "Emergency Type" : "Natural Disaster",
      "address" : "Lapaz Tarlac",
      "emergencyNum" : "9876876650987",
      "name" : "Rafael Campos",
      "phoneNum" : "089098786876"
    }
  }
}

这是我的 onMapReady():

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

        DatabaseReference rootRef = FirebaseDatabase.getInstance().getReference();
        DatabaseReference locationRef = rootRef.child("User Location");



        locationRef.addChildEventListener(new ChildEventListener() {
            @Override
            public void onChildAdded(@NonNull DataSnapshot snapshot, @Nullable String previousChildName) {


                    LocationSend send = snapshot.getValue(LocationSend.class);
                    LatLng location = new LatLng(send.getLatitude(), send.getLongitude());
                    mMap.addMarker(new MarkerOptions().position(location).title(getCompleteAddress(send.getLatitude(), send.getLongitude())));
                    mMap.moveCamera(CameraUpdateFactory.newLatLng(location));
                    mMap.moveCamera(CameraUpdateFactory.newLatLngZoom(location, 14F));
                    mMap.setInfoWindowAdapter(new InfoWindowAdapter(Retrieve.this));
                    Log.d("TAG", "latitude, longitude");
                    notification();
            }

            @Override
            public void onChildChanged(@NonNull DataSnapshot snapshot, @Nullable String previousChildName) {
                LocationSend send = snapshot.getValue(LocationSend.class);
                notification();
            }

            @Override
            public void onChildRemoved(@NonNull DataSnapshot snapshot) {

            }

            @Override
            public void onChildMoved(@NonNull DataSnapshot snapshot, @Nullable String previousChildName) {

            }

            @Override
            public void onCancelled(@NonNull DatabaseError error) {

            }
        });
    }

我的适配器：

public class InfoWindowAdapter implements GoogleMap.InfoWindowAdapter{

    Context context;
    public InfoWindowAdapter(Context context){
        this.context = context;
    }

    @Nullable
    @Override
    public View getInfoWindow(@NonNull Marker marker) {
        View infoView = LayoutInflater.from(context).inflate(R.layout.infowindow, null);
        TextView title = infoView.findViewById(R.id.title);
        TextView alert = infoView.findViewById(R.id.alert);
        TextView type = infoView.findViewById(R.id.type);
        title.setText(marker.getTitle());
        alert.setText(marker.getSnippet());
        type.setText(marker.getSnippet());

        return infoView;
    }

    @Nullable
    @Override
    public View getInfoContents(@NonNull Marker marker) {
        return null;
    }
}

Answer 1

根据您最后的评论：

In the Users node, the Name, Emergency Type, and Alert Level

为了能够获取与特定用户相对应的指示字段的值并将它们添加到 Google 地图，请使用以下代码行：

String uid = FirebaseAuth.getInstance().getCurrentUser().getUid();
DatabaseReference rootRef = FirebaseDatabase.getInstance().getReference();
DatabaseReference userLocationRef = rootRef.child("User Location").child(uid);
userLocationRef.get().addOnCompleteListener(new OnCompleteListener<DataSnapshot>() {
    @Override
    public void onComplete(@NonNull Task<DataSnapshot> userLocationTask) {
        if (userLocationTask.isSuccessful()) {
            DataSnapshot userLocationSnapshot = userLocationTask.getResult();
            double latitude = userLocationSnapshot.child("latitude").getValue(Double.class);
            double longitude = userLocationSnapshot.child("longitude").getValue(Double.class);

            DatabaseReference uidRef = rootRef.child("Users").child(uid);
            uidRef.get().addOnCompleteListener(new OnCompleteListener<DataSnapshot>() {
                @Override
                public void onComplete(@NonNull Task<DataSnapshot> userTask) {
                    if (userTask.isSuccessful()) {
                        DataSnapshot userSnapshot = userTask.getResult();
                        String name = userSnapshot.child("Name").getValue(String.class);
                        String emergencyType = userSnapshot.child("Emergency Type").getValue(String.class);
                        String alertLevel = userSnapshot.child("Alert Level").getValue(String.class);

                        MarkerOptions markerOptions = new MarkerOptions();
                        LatLng latLng = new LatLng(latitude, longitude);
                        markerOptions.position(latLng);
                        markerOptions.title(name + "/" + emergencyType + "/" + alertLevel);
                        googleMap.addMarker(markerOptions);
                    } else {
                        Log.d("TAG", userTask.getException().getMessage()); //Don't ignore potential errors!
                    }
                }
            });
        } else {
            Log.d("TAG", userLocationTask.getException().getMessage()); //Don't ignore potential errors!
        }
    }
});

以下代码的结果将是添加一个与 Google 地图上的用户位置相对应的标记。标记的标题将包含名称、紧急类型和警报级别。

这确实适用于单个用户，如果您需要显示所有用户，则只需使用 getChildren() 方法遍历 DataSnapshot object，如下所示：

String uid = FirebaseAuth.getInstance().getCurrentUser().getUid();
DatabaseReference rootRef = FirebaseDatabase.getInstance().getReference();
DatabaseReference userLocationRef = rootRef.child(uid).child("User Location");
userLocationRef.get().addOnCompleteListener(new OnCompleteListener<DataSnapshot>() {
    @Override
    public void onComplete(@NonNull Task<DataSnapshot> userLocationTask) {
        if (userLocationTask.isSuccessful()) {
            for (DataSnapshot userLocationSnapshot : userLocationTask.getResult().getChildren()) {
                double latitude = userLocationSnapshot.child("latitude").getValue(Double.class);
                double longitude = userLocationSnapshot.child("longitude").getValue(Double.class);

                DatabaseReference usersRef = rootRef.child("Users").child(uid);
                usersRef.get().addOnCompleteListener(new OnCompleteListener<DataSnapshot>() {
                    @Override
                    public void onComplete(@NonNull Task<DataSnapshot> userTask) {
                        if (userTask.isSuccessful()) {
                            for (DataSnapshot userSnapshot : userTask.getResult().getChildren()) {
                                String name = userSnapshot.child("name").getValue(String.class);
                                String emergencyType = userSnapshot.child("Emergency Type").getValue(String.class);
                                String alertLevel = userSnapshot.child("Alert Level").getValue(String.class);

                                MarkerOptions markerOptions = new MarkerOptions();
                                LatLng latLng = new LatLng(latitude, longitude);
                                markerOptions.position(latLng);
                                markerOptions.title(name + "/" + emergencyType + "/" + alertLevel);
                                googleMap.addMarker(markerOptions);
                            }
                        } else {
                            Log.d("TAG", userTask.getException().getMessage()); //Don't ignore potential errors!
                        }
                    }
                });
            }
        } else {
            Log.d("TAG", userLocationTask.getException().getMessage()); //Don't ignore potential errors!
        }
    }
});

将来自 Firebase 的数据显示到自定义信息中 Window

Displaying data from Firebase into custom Info Window

java

android

google-maps

firebase

firebase-realtime-database