인프런 커뮤니티 질문&답변

강의 잘 보고 있습니다

다름이 아니라 로그인 로그아웃 버튼도 만들었고

수업에 나온 것처럼 똑같이 코드를 썼는데도

막상 작동하면 uid까진 출력되는데

문제는

1) 로그아웃 버튼을 누르면 null 메세지가 출력이 안 됩니다

2) 그렇다고 로그아웃 버튼을 누르고 로그인 되어있던 계정을 누르면 toast로 써둔 "로그인 성공"이라는 메세지가 안 뜸

일단 MainActivity.kt에 쓴 코드와

activity_main.xml에 쓴 코드를 올리겠습니다

//MainActivity.kt에 쓴 코드

package com.example.mysampleapp
import com.example.mysampleapp.databinding.ActivityMainBinding
import android.os.Bundle
import android.widget.Button
import android.widget.EditText
import android.widget.Toast
import androidx.activity.enableEdgeToEdge
import androidx.appcompat.app.AppCompatActivity
import androidx.core.view.ViewCompat
import androidx.core.view.WindowInsetsCompat
import androidx.databinding.DataBindingUtil
import com.google.firebase.auth.FirebaseAuth
import com.google.firebase.auth.ktx.auth
import com.google.firebase.ktx.Firebase

class MainActivity : AppCompatActivity() {

    private lateinit var auth: FirebaseAuth

    private lateinit var binding : ActivityMainBinding

    override fun onCreate(savedInstanceState: Bundle?) {
        // Initialize Firebase Auth
        auth = Firebase.auth
        super.onCreate(savedInstanceState)
        enableEdgeToEdge()
        setContentView(R.layout.activity_main)

        Toast.makeText(this, auth.currentUser?.uid.toString(),Toast.LENGTH_SHORT).show()

        binding = DataBindingUtil.setContentView(this, R.layout.activity_main)

        val joinBtnClicked = findViewById<Button>(R.id.joinBtn)
        joinBtnClicked.setOnClickListener {
//              첫번째 방법
//            val email = findViewById<EditText>(R.id.emailArea)
//            val pwd = findViewById<EditText>(R.id.pwdArea)

            //두번째 방법
            val email = binding.emailArea
            val pwd = binding.pwdArea

            auth.createUserWithEmailAndPassword(
                email.text.toString(),
                pwd.text.toString()

                )
                .addOnCompleteListener(this) { task ->
                    if (task.isSuccessful) {
                        Toast.makeText(this,"ok",Toast.LENGTH_SHORT).show()
                    } else {
                        Toast.makeText(this,"no",Toast.LENGTH_SHORT).show()
                    }
                }

                binding.logoutBtn.setOnClickListener{
                    auth.signOut()
                    Toast.makeText(this,auth.currentUser?.uid.toString(),Toast.LENGTH_SHORT).show()
                }

                binding.loginBtn.setOnClickListener{

                    val email = binding.emailArea
                    val pwd = binding.pwdArea

                    auth.signInWithEmailAndPassword(
                        email.text.toString(),
                        pwd.text.toString()
                    )
                        .addOnCompleteListener(this) { task ->
                            if (task.isSuccessful) {
                                //성공하면
                                Toast.makeText(this, "로그인 성공", Toast.LENGTH_SHORT).show()
                                //성공하면 UID 값을 띄워보자↓
                                Toast.makeText(this,auth.currentUser?.uid.toString(),Toast.LENGTH_SHORT).show()

                            } else {
                                //실패하면
                                Toast.makeText(this, "로그인 실패", Toast.LENGTH_SHORT).show()


                            }
                        }
                }
        }
    }
}

//activity_main.xml에 쓴 코드

<?xml version="1.0" encoding="utf-8"?>
<layout>
    <LinearLayout
        xmlns:android="http://schemas.android.com/apk/res/android"
        xmlns:app="http://schemas.android.com/apk/res-auto"
        xmlns:tools="http://schemas.android.com/tools"
        android:id="@+id/main"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        tools:context=".MainActivity"
        android:orientation="vertical">

        <EditText
            android:id="@+id/emailArea"
            android:hint="email"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"/>

        <EditText
            android:id="@+id/pwdArea"
            android:hint="pwd"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"/>

        <Button
            android:id="@+id/joinBtn"
            android:text="회원가입"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"/>
        
        <Button
            android:id="@+id/logoutBtn"
            android:text="LOGOUT"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"/>

        <Button
            android:id="@+id/loginBtn"
            android:text="LOGIN"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"/>



    </LinearLayout>
</layout>

긴 글 읽어주심에 감사합니다....😥😥