Zhuinden

    public class MyFragment
            extends Fragment {
    
        public MyFragment() {
            super(R.layout.my_fragment);
        }
    
        private int selectedIndex = 0;
    
        private FirstFragment firstFragment;

stevdza-san

package com.example.protodatastoretest

import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import android.util.Log
import androidx.lifecycle.ViewModelProvider
import kotlinx.android.synthetic.main.activity_main.*

class MainActivity : AppCompatActivity() {