the id name is also the same id in the menu setting file; it is the same ID name and also imports the R; but also shows errors.... please give the reason and solution with R.id..... statement; the R.id.action_home always has errors although I import the R; please provide the solution with R.id..... statements; package com.example.dropdown; import static com.example.dropdown.R.*; import com.example.dropdown.R; import android.content.SharedPreferences; import android.os.Bundle; import android.view.MenuItem; import android.view.View; import android.widget.Toast; import androidx.appcompat.app.AppCompatActivity; import androidx.appcompat.widget.PopupMenu; private boolean onMenuItemClick(MenuItem menuItem) { switch (menuItem.getItemId()) { case R.id.action_home: Toast.makeText(this, "Home clicked", Toast.LENGTH_SHORT).show(); break; case R.id.action_light_mode: Toast.makeText(this, "Light Mode activated", Toast.LENGTH_SHORT).show(); setLightMode(); break; case R.id.action_dark_mode: Toast.makeText(this, "Dark Mode activated", Toast.LENGTH_SHORT).show(); setDarkMode(); break; default: return false; } return true; }