Menu de contexto não responde ao clique

package pizzaria.lafornalha.fragment.dialog;

import pizzaria.lafornalha.R;
import pizzaria.lafornalha.activity.CardapioActivity;
import pizzaria.lafornalha.modelo.adapter.PedidosAdapter;
import android.os.Bundle;
import android.support.v4.app.DialogFragment;
import android.view.ContextMenu;
import android.view.ContextMenu.ContextMenuInfo;
import android.view.LayoutInflater;
import android.view.MenuInflater;
import android.view.MenuItem;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.ViewGroup;
import android.widget.AdapterView.AdapterContextMenuInfo;
import android.widget.Button;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.Toast;

public class PedidosDialog extends DialogFragment implements OnClickListener {

	@Override
	public View onCreateView(LayoutInflater inflater, ViewGroup container,
			Bundle savedInstanceState) {
		View v = inflater.inflate(R.layout.dialog_pedidos, container);

		getDialog().getWindow().requestFeature(STYLE_NO_TITLE);

		ListView listview = (ListView) v.findViewById(R.id.listview_pedidos);
		listview.setAdapter(new PedidosAdapter(CardapioActivity.pedidos,
				getActivity()));
		registerForContextMenu(listview);

		Button botao = (Button) v.findViewById(R.id.botao_pedir_dialog);
		TextView valor = (TextView) v.findViewById(R.id.valor_total_pedido);

		botao.setOnClickListener(this);

		return v;

	}

	@Override
	public void onClick(View arg0) {
		// TODO Auto-generated method stub

	}

	@Override
	public void onCreateContextMenu(ContextMenu menu, View v,
			ContextMenuInfo menuInfo) {
		MenuInflater inflater = getActivity().getMenuInflater();
		inflater.inflate(R.menu.menu_contexto_pedido, menu);
	}

	@Override
	public boolean onContextItemSelected(MenuItem item) {
		AdapterContextMenuInfo info = (AdapterContextMenuInfo) item
				.getMenuInfo();
		Toast.makeText(getActivity(), "Menu de Contexto Clicado",
				Toast.LENGTH_SHORT).show();
		return true;
	}
}