Having problem with R.menu

[arash.moeen]

I've been trying to learn about menus in android and just got this example.

package de.vogella.android.menuitem;

import android.app.Activity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuInflater;





public class MainActivity extends Activity {
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
    }
    
    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        MenuInflater inflater = getMenuInflater();
        inflater.inflate(R.menu.game_menu, menu);
        return true;
    }
}

but somehow for some unknown reason to me the R.menu gives me an error on the word menu and it say it can't be resolved, any idea ? thnx in advance