java - Android Firebase通过重新登录删除所有用户数据

Question

我正在尝试在 Firebase 实时数据库中创建用户表。但是，每次用户重新登录时，他之前输入的数据都会被删除或覆盖。无法理解应该如何更改它。

  private void firebaseAuthWithGoogle(GoogleSignInAccount account) {





    AuthCredential credential = GoogleAuthProvider.getCredential(account.getIdToken(), null);
    mAuth.signInWithCredential(credential)
            .addOnCompleteListener(this, new OnCompleteListener<AuthResult>() {
                @Override
                public void onComplete(@NonNull Task<AuthResult> task) {
                    if (task.isSuccessful()) {



                        Toast.makeText(RegisterActivity.this,"Registration Is Succesfull",Toast.LENGTH_LONG).show();
                        // Sign in success, update UI with the signed-in user's information
                        Log.d(TAG, "signInWithCredential:success");

                        FirebaseUser user=mAuth.getCurrentUser();

                        final String databaseUserName=user.getDisplayName();


                        String name=mAuth.getCurrentUser().getDisplayName();

                        DatabaseReference myRootRef = FirebaseDatabase.getInstance().getReference().child("Users");


                        DatabaseReference userNameRef =  myRootRef.child(databaseUserName);


                    //after that user is redirected to the main account activity.
                        Intent accountIntent = new Intent(RegisterActivity.this,UserAccountActivity.class);
                        accountIntent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
                        startActivity(accountIntent);


                    } else {
                        // If sign in fails, display a message to the user.
                        Log.w(TAG, "signInWithCredential:failure", task.getException());
                        Toast.makeText(RegisterActivity.this, "Authentication failed.",
                                Toast.LENGTH_SHORT).show();

                        // if signing up task is unsuccesfull we do make a error indication pretty much.
                        FirebaseAuthException e = (FirebaseAuthException )task.getException();
                        Toast.makeText(RegisterActivity.this, "Failed Registration: "+e.getMessage(), Toast.LENGTH_SHORT).show();

                        Log.e("LoginActivity", "Failed Registration", e);

                    }


                }
            });



}

因此，一旦我运行代码，第一次它工作得很好，并说我编辑并添加了其他用户信息，但一旦用户注销并重新输入，所有内容都会被清除，并再次创建节点。

Answer 1

这里您将数据保存在数据库中:

DatabaseReference myRootRef = FirebaseDatabase.getInstance().getReference().child("Users");
DatabaseReference userNameRef =  myRootRef.child(databaseUserName);

现在第二次，数据没有被删除或清除，它不能被神奇地删除，数据被覆盖。您需要做的就是添加一个 push() ，它将为每次登录创建一个随机 ID。

就像这样:

DatabaseReference myRootRef = FirebaseDatabase.getInstance().getReference().child("Users").push();
DatabaseReference userNameRef =  myRootRef.child(databaseUserName)

编辑:

auth.createUserWithEmailAndPassword(email, password)
                    .addOnCompleteListener(Activity_name_here.this, new OnCompleteListener<AuthResult>() {
                        @Override
                        public void onComplete(@NonNull Task<AuthResult> task) {
                            Toast.makeText(getApplicationContext(), "createUserWithEmail:onComplete:" + task.isSuccessful(), Toast.LENGTH_SHORT).show();
                            // If sign in fails, display a message to the user. If sign in succeeds
                            // the auth state listener will be notified and logic to handle the
                            // signed in user can be handled in the listener.
                            if (!task.isSuccessful()) {
                                Toast.makeText(getApplicationContext(), "Authentication failed." + task.getException(),
                                        Toast.LENGTH_SHORT).show();
                            } else {