Firestore - How to know the id from a document?

Question

How I can know the ID from a document in firestore - android studio?

In this code, you can see, how I create a new account, here I want to create the new document with the user id, but he don't create with this id, he put other-one.

if (!confirmarCampos(nome,email,eNdata,id,password)){

        fAuth.createUserWithEmailAndPassword(email, password).addOnCompleteListener(new OnCompleteListener<AuthResult>() {

            @Override
            public void onComplete(@NonNull Task<AuthResult> task) {

                if (task.isSuccessful()) {
                    pessoa.put("nome", nome);
                    pessoa.put("email", email);
                    pessoa.put("ano", eNdata);
                    pessoa.put("idBicicleta", id);
                    pessoa.put("distancia", 0);
                    pessoa.put("pontos", 0);

                    db.collection("pessoa")
                            .document(user_id) //here i put the reference from user id
                            .set(pessoa)
                            .addOnCompleteListener(new OnCompleteListener<Void>() {
                                @Override
                                public void onComplete(@NonNull Task<Void> task) {

                                    if(task.isSuccessful()){
                                        Toast.makeText(Registar.this,"Perfil Criado com Sucesso", Toast.LENGTH_SHORT).show();


                                    }else{
                                        String erro = task.getException().getMessage();
                                        Toast.makeText(Registar.this,"ERRO :" + erro, Toast.LENGTH_SHORT).show();
                                    }
                                }
                            });
                    Intent iConfirmar = new Intent(Registar.this, Login.class);
                    startActivity(iConfirmar);
                    finish();
                }else{
                   Toast.makeText(Registar.this, "O email já existe", Toast.LENGTH_LONG).show();
                }
            }
        });
    }

Here you can see the id from the new user.

Here you can see the id from the new document it's different from the user id. And because of that, I can't work with the values inside of a document, because I want to set the values into a profile.xml .

Document id : Thank you for helping.

Answer 1

here, how did you get the user_id?

try to get user id like this way,

if (task.isSuccessful()) {
    // Sign up in success, update UI with the signed-in user's information
    FirebaseUser user = mAuth.getCurrentUser();
    if (user != null) {
        user_id = user.getUid();               
    }           
}