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import android.os.Bundle;
import android.support.design.widget.Snackbar;
import android.support.v7.app.AppCompatActivity;
import android.view.View;

import androidx.navigation.NavController;
import androidx.navigation.Navigation;
import androidx.navigation.ui.AppBarConfiguration;
import androidx.navigation.ui.NavigationUI;

import com.example.myapplication.go.databinding.MainBinding;

import com.example.myapplication.R;

public class HiddenActivity extends AppCompatActivity {

private AppBarConfiguration appBarConfiguration;
 private MainBinding binding;

 @Override
 protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);

 binding = MainBinding.inflate(getLayoutInflater());
 setContentView(binding.getRoot());

 setSupportActionBar(binding.toolbar);

 NavController navController = Navigation.findNavController(this, R.id.nav_host_fragment_content_hidden);
 appBarConfiguration = new AppBarConfiguration.Builder(navController.getGraph()).build();
 NavigationUI.setupActionBarWithNavController(this, navController, appBarConfiguration);

 binding.fab.setOnClickListener(new View.OnClickListener() {
@Override
 public void onClick(View view) {
Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
.setAction("Action", null).show();
 }
});
 }

@Override
 public boolean onSupportNavigateUp() {
NavController navController = Navigation.findNavController(this, R.id.nav_host_fragment_content_hidden);
 return NavigationUI.navigateUp(navController, appBarConfiguration)
|| super.onSupportNavigateUp();
 }
}