package one.nem.lacerta; import androidx.appcompat.app.AppCompatActivity; import androidx.fragment.app.FragmentManager; import androidx.navigation.NavController; import androidx.navigation.fragment.NavHostFragment; import androidx.navigation.ui.NavigationUI; import android.os.Bundle; import com.google.android.material.bottomnavigation.BottomNavigationView; public class MainActivity extends AppCompatActivity { @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); // Debug FragmentManager supportFragmentManager = getSupportFragmentManager(); NavHostFragment navHostFragment = (NavHostFragment) supportFragmentManager.findFragmentById(R.id.nav_host_fragment); NavController navController = navHostFragment.getNavController(); BottomNavigationView bottomNavigationView = findViewById(R.id.bottom_nav); NavigationUI.setupWithNavController(bottomNavigationView, navController); } }