How to delete a Firebase user from Android App?

Question

I\'m trying to code a Delete User method in my Android App, but I have some issues each time I execute it. This method will be executed when a user pushes the D

Answer 1

First of all, you need to store the auth token or the password at the moment your user is logging in. If your app doesn't provide such as Google Sign-in, Facebook Sign-in or others, you just need to store the password.

//If there's any, delete all stored content from this user on Real Time Database. 
yourDatabaseReferenceNode.removeValue();

//Getting the user instance.
final FirebaseUser user = FirebaseAuth.getInstance().getCurrentUser();

if (user != null) {
    //You need to get here the token you saved at logging-in time.
    String token = "userSavedToken";
    //You need to get here the password you saved at logging-in time.
    String password = "userSavedPassword";

    AuthCredential credential;

    //This means you didn't have the token because user used like Facebook Sign-in method.
    if (token == null) {
       credential = EmailAuthProvider.getCredential(user.getEmail(), password);
    } else {
       //Doesn't matter if it was Facebook Sign-in or others. It will always work using GoogleAuthProvider for whatever the provider.
       credential = GoogleAuthProvider.getCredential(token, null);
    }

    //We have to reauthenticate user because we don't know how long 
    //it was the sign-in. Calling reauthenticate, will update the 
    //user login and prevent FirebaseException (CREDENTIAL_TOO_OLD_LOGIN_AGAIN) on user.delete()
    user.reauthenticate(credential)
            .addOnCompleteListener(new OnCompleteListener<Void>() {
                    @Override
                    public void onComplete(@NonNull Task<Void> task) {
                        //Calling delete to remove the user and wait for a result.
                        user.delete().addOnCompleteListener(new OnCompleteListener<Void>() {
                            @Override
                            public void onComplete(@NonNull Task<Void> task) {
                                if (task.isSuccessful()) {
                                    //Ok, user remove
                                } else {
                                    //Handle the exception
                                    task.getException();
                                }
                            }
                        });
                    }
                });    
}        

Answer 2

If you are using AuthUI or FirebaseAuth you can just do the following

 AuthUI.getInstance().delete(context).addOnSuccessListener {
           
 }.addOnFailureListener{

 }

OR

FirebaseAuth.getInstance().currentUser.delete().addOnSuccessListener...