How to update specific fields in Firebase JSON node

Question

I'm working on Geo location Android application which is using Firebase for back end and database.

Here is my structure for the data in my database.

Here is mu User.java class.

@IgnoreExtraProperties
public class User {

    public String fullName;
    public String email;
    public String longitude;
    public String latitude;

    public String getLongitude() {
        return longitude;
    }

    public void setLongitude(String longitude) {
        this.longitude = longitude;
    }

    public String getLatitude() {
        return latitude;
    }

    public void setLatitude(String latitude) {
        this.latitude = latitude;
    }


    public User() {

    }

    public String getFullName() {
        return fullName;
    }

    public void setFullName(String fullName) {
        this.fullName = fullName;
    }

    public String getEmail() {
        return email;
    }

    public void setEmail(String email) {
        this.email = email;
    }

What I want to do.

• I want my application to be updating the JSON node of the user which I'm using at the moment. Those are the two fields shown on the picture Longitude and Latitude.

How I'm doing it now?

• I'm now creating user from the User.java class and then by setLongitude and setLatidude I'm adding the data and then call the setValue method.

• Here is the code sniped for it.

  dbRef = FirebaseDatabase.getInstance().getReference();
  mAuth = FirebaseAuth.getInstance();
  User user = new User();
  String currentUserId = mAuth.getCurrentUser().getUid();
  user.setLatitude(String.valueOf(userLocation.latitude));
  user.setLongitude(String.valueOf(userLocation.longitude));
  dbRef.child("users").child(currentUserId).setValue(user).addOnCompleteListener(new OnCompleteListener<Void>() {
      @Override
      public void onComplete(@NonNull Task<Void> task) {
          if (task.isSuccessful()) {
              Log.i("Info", "updateUser:success");
          } else {
              Log.i("Info", "updateUser:failure");
          }
      }
  });
  

What is wrong?

• At this moment I don't have my database updated and instead of that I end up with the fields deleted and then longitude and latitude fields added. That is also shown on the image above.

Answer 1

The problem is that you're not setting fullName and email when setting latitude and longitude, then those field are null. setValue() will erase the old object and add the new one with the fields null. You should be doing an updateChildren instead of setValue.

Map<String, Object> latLong = new HashMap<>();
latLong.put("latitude", "123");
latLong.put("longitude", "123");

dbRef.child("users").child(currentUserId).updateChildren(latLong).addOnCompleteListener(new OnCompleteListener<Void>() {
            @Override
            public void onComplete(@NonNull Task<Void> task) {
                if (task.isSuccessful()) {
            Log.i("Info", "updateUser:success");
        } else {
            Log.i("Info", "updateUser:failure");
        }
            }
        });

You can keep using your code if you set the email and fullName alongside with latitude and longitude.