XNAGameStudio/Samples/NGSMSample_4_0/NetworkStateManagement/Networking/AvailableSessionMenuEntry.cs

#region File Description
//-----------------------------------------------------------------------------
// AvailableSessionMenuEntry.cs
//
// Microsoft XNA Community Game Platform
// Copyright (C) Microsoft Corporation. All rights reserved.
//-----------------------------------------------------------------------------
#endregion

#region Using Statements
using System;
using Microsoft.Xna.Framework;
using Microsoft.Xna.Framework.Net;
#endregion

namespace NetworkStateManagement
{
    /// <summary>
    /// Helper class customizes the standard MenuEntry class
    /// for displaying AvailableNetworkSession objects.
    /// </summary>
    class AvailableSessionMenuEntry : MenuEntry
    {
        #region Fields

        AvailableNetworkSession availableSession;
        bool gotQualityOfService;

        #endregion

        #region Properties


        /// <summary>
        /// Gets the available network session corresponding to this menu entry.
        /// </summary>
        public AvailableNetworkSession AvailableSession
        {
            get { return availableSession; }
        }


        #endregion

        #region Initialization


        /// <summary>
        /// Constructs a menu entry describing an available network session.
        /// </summary>
        public AvailableSessionMenuEntry(AvailableNetworkSession availableSession)
            : base(GetMenuItemText(availableSession))
        {
            this.availableSession = availableSession;
        }


        /// <summary>
        /// Formats session information to create the menu text string.
        /// </summary>
        static string GetMenuItemText(AvailableNetworkSession session)
        {
            int totalSlots = session.CurrentGamerCount +
                             session.OpenPublicGamerSlots;

            return string.Format("{0} ({1}/{2})", session.HostGamertag,
                                                  session.CurrentGamerCount,
                                                  totalSlots);
        }


        #endregion

        #region Update


        /// <summary>
        /// Updates the menu item text, adding information about the network
        /// quality of service as soon as that becomes available.
        /// </summary>
        public override void Update(MenuScreen screen, bool isSelected,
                                                       GameTime gameTime)
        {
            base.Update(screen, isSelected, gameTime);

            // Quality of service data can take some time to query, so it will not
            // be filled in straight away when NetworkSession.Find returns. We want
            // to display the list of available sessions straight away, and then
            // fill in the quality of service data whenever that becomes available,
            // so we keep checking until this data shows up.
            if (screen.IsActive && !gotQualityOfService)
            {
                QualityOfService qualityOfService = availableSession.QualityOfService;

                if (qualityOfService.IsAvailable)
                {
                    TimeSpan pingTime = qualityOfService.AverageRoundtripTime;

                    Text += string.Format(" - {0:0} ms", pingTime.TotalMilliseconds);

                    gotQualityOfService = true;
                }
            }
        }


        #endregion
    }
}