How to return a DocumentSnapShot as a result of a method?

Question

A custom object that takes a parameter of (DocumentSnapShot documentsnapShot). also is an inner object from Firebase that retrieves a snapshot and set the values to my custo

Answer 1

Use LiveData as return type and observe the changes of it's value to execute desired operation.

private MutableLiveData userSettingsMutableLiveData = new MutableLiveData<>();

public MutableLiveData getUserSettings(DocumentSnapshot documentSnapshot){

    DocumentReference mSettings = mFirebaseFirestore.collection("user_account_settings").document(userID);
    mSettings.get().addOnSuccessListener(new OnSuccessListener() {
        @Override
        public void onSuccess(DocumentSnapshot documentSnapshot) {
            UserAccountSettings settings = documentSnapshot.toObject(UserAccountSettings.class);
            settings.setDisplay_name(documentSnapshot.getString("display_name"));
            settings.setUsername(documentSnapshot.getString("username"));
            settings.setWebsite(documentSnapshot.getString("website"));
            settings.setProfile_photo(documentSnapshot.getString("profile_photo"));
            settings.setPosts(documentSnapshot.getLong("posts"));
            settings.setFollowers(documentSnapshot.getLong("followers"));
            settings.setFollowing(documentSnapshot.getLong("following"));

            userSettingsMutableLiveData.setValue(settings);
        }
    });

    return userSettingsMutableLiveData;
}

Then from your Activity/Fragment observe the LiveData and inside onChanged do your desired operation.

getUserSettings().observe(this, new Observer() {
    @Override
    public void onChanged(UserAccountSettings userAccountSettings) {
        //here, do whatever you want on `userAccountSettings`
    }
});