/// <summary>
        /// Responds to user input, changing the selected entry and accepting
        /// or cancelling the menu.
        /// </summary>
        public override void HandleInput(InputState input)
        {
            // Move to the previous menu entry?
            if (input.IsMenuUp(ControllingPlayer))
            {
                selectedEntry--;

                if (selectedEntry < 0)
                    selectedEntry = menuEntries.Count - 1;
            }

            // Move to the next menu entry?
            if (input.IsMenuDown(ControllingPlayer))
            {
                selectedEntry++;

                if (selectedEntry >= menuEntries.Count)
                    selectedEntry = 0;
            }

            // Accept or cancel the menu? We pass in our ControllingPlayer, which may
            // either be null (to accept input from any player) or a specific index.
            // If we pass a null controlling player, the InputState helper returns to
            // us which player actually provided the input. We pass that through to
            // OnSelectEntry and OnCancel, so they can tell which player triggered them.
            PlayerIndex playerIndex;

            if (input.IsMenuSelect(ControllingPlayer, out playerIndex))
            {
                OnSelectEntry(selectedEntry, playerIndex);
            }
            else if (input.IsMenuCancel(ControllingPlayer, out playerIndex))
            {
                OnCancel(playerIndex);
            }
        }
        /// <summary>
        /// Responds to user input, accepting or cancelling the message box.
        /// </summary>
        public override void HandleInput(InputState input)
        {
            PlayerIndex playerIndex;

            // We pass in our ControllingPlayer, which may either be null (to
            // accept input from any player) or a specific index. If we pass a null
            // controlling player, the InputState helper returns to us which player
            // actually provided the input. We pass that through to our Accepted and
            // Cancelled events, so they can tell which player triggered them.
            if (input.IsMenuSelect(ControllingPlayer, out playerIndex))
            {
                // Raise the accepted event, then exit the message box.
                if (Accepted != null)
                    Accepted(this, new PlayerIndexEventArgs(playerIndex));

                ExitScreen();
            }
            else if (input.IsMenuCancel(ControllingPlayer, out playerIndex))
            {
                // Raise the cancelled event, then exit the message box.
                if (Cancelled != null)
                    Cancelled(this, new PlayerIndexEventArgs(playerIndex));

                ExitScreen();
            }
        }