auth.currentUser?.uid.toString() 가 null 이 나와요

auth.currentUser?.uid.toString() 가 null 이 나와요

잘나왔었는데 몇시간뒤에 하니까 null 이 나옵니다.

로그인 -> 어플종료 -> 다시 어플 키면 uid가 나오는데

MypageActivity가면 uid가 null입니다.

firebase는 이상없이 작동합니다

package com.example.sogating.setting

import android.os.Bundle
import android.util.Log
import android.widget.ImageView
import android.widget.TextView
import androidx.activity.enableEdgeToEdge
import androidx.appcompat.app.AppCompatActivity
import androidx.core.view.ViewCompat
import androidx.core.view.WindowInsetsCompat
import com.example.sogating.R
import com.example.sogating.auth.UserDataModel
import com.example.sogating.utils.FirebaseAuthUtils
import com.example.sogating.utils.FirebaseRef
import com.google.firebase.database.DataSnapshot
import com.google.firebase.database.DatabaseError
import com.google.firebase.database.ValueEventListener

class MyPageActivity : AppCompatActivity() {

    private val TAG = "MyPageActivity"

    private val uid = FirebaseAuthUtils.getUid()

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_my_page)

        getMyData()
    }

    private fun getMyData() {

        val myImage = findViewById<ImageView>(R.id.myImage)
        val myUid = findViewById<TextView>(R.id.myUid)
        val myNickname = findViewById<TextView>(R.id.myNickname)
        val myAge = findViewById<TextView>(R.id.myAge)
        val myCity = findViewById<TextView>(R.id.myCity)
        val myGender = findViewById<TextView>(R.id.myGender)

        val postListener = object : ValueEventListener {
            override fun onDataChange(dataSnapshot: DataSnapshot) {
                // Get Post object and use the values to update the UI

                Log.d(TAG, dataSnapshot.toString())
                val data = dataSnapshot.getValue(UserDataModel::class.java)

//                myUid.text = data!!.uid
//                myNickname.text = data.nickname
//                myAge.text = data.age
//                myCity.text = data.city
//                myGender.text = data.gender

            }

            override fun onCancelled(databaseError: DatabaseError) {
                // Getting Post failed, log a message
                Log.w(TAG, "loadPost:onCancelled", databaseError.toException())
            }
        }
        
        // why null ?
        Log.d(TAG, uid)
        FirebaseRef.userinfoRef.child(uid).addValueEventListener(postListener)
    }
}

package com.example.sogating.utils

import com.google.firebase.auth.FirebaseAuth

class FirebaseAuthUtils {

    companion object {

        private lateinit var auth: FirebaseAuth

        fun getUid() : String {
            auth = FirebaseAuth.getInstance()

            return auth.currentUser?.uid.toString()
        }
    }
}

 자세한 소스 입니다.

https://github.com/dongmyoungLee/sogating_app