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I'm making a blackjack game where a card needs to be shown a second after the last card. I've googled it and saw Thread.Sleep - but people said timers would be better for that. How can I do this with timers? Thanks!

Tom
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    You shouldn't use either (*especially* don't use `Thread.Sleep`). Accumulate the `gameTime.ElapsedGameTime` when `Game.Update` is called. – Andrew Russell Aug 23 '11 at 05:52
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    @Andrew Russel +1 Thread.Sleep should be avoided in 99.9% of cases where you might be tempted to use it! – MattDavey Aug 23 '11 at 08:05
  • Can you give an example? – Tom Aug 23 '11 at 08:43
  • @Matt - why? One of the reasons for implementing functionality in seperate threads is that such actions can be simply taken 'in-line' - if a protocol needs a two second delay, sleep(2000), is a one-liner that does not adversely affect any other thread or require any timer-driven state-machine. Sleep() can, of course be misused, like almost anything. – Martin James Aug 23 '11 at 08:45
  • @Martin James there is much discussion on the subject.. http://stackoverflow.com/questions/1096794/is-sleep-evil – MattDavey Aug 23 '11 at 13:32

2 Answers2

11
float WaitTimeToShowCard = 0;


public void Update(GameTime gametime)
{

    if (HasToShowCard ()) 
    {
         WaitTimeToShowCard = 1;
    }

    if (WaitTimeToShowCard >0)
    {
         WaitTimeToShowCard -= (float) gametime.Elapsed.TotalSeconds;
         if (WaitTimeToShowCard <=0)
         {
             WaitTimeToShowCard = 0;
             ShowCard();
         } 
    }
}

or

public class Timer
{
    public Action Trigger;
    public float Interval;
    float Elapsed;

    Timer() {}

    public void Update(float Seconds)
    {
        Elapsed+= Seconds;
        if (Elapsed>= Interval)
        {
             Trigger.Invoke();
             Destroy();
        }
    }

    public void Destroy()
    {
        TimerManager.Remove(this);
    }

    public static void Create(float Interval, Action Trigger)
    {
        Timer Timer = new Timer() { Interval = Interval, Trigger = Trigger }
        TimerManager.Add(this);
    }
}


public class TimerManager : GameComponent
{
     List<Timer> ToRemove = new List<Timer>();
     List<Timer> Timers = new List<Timer>();

     public static TimerManager Instance;

     public static void Add(Timer Timer) { Instance.Timers.Add( Timer ); }
     public static void Remove(Timer Timer) { Instance.ToRemove.Add(Timer); }

     public void Update(GameTime gametime)
     {
         foreach (Timer timer in ToRemove) Timers.Remove(timer);
         ToRemove.Clear();
         foreach (Timer timer in Timers) timer.Update( (float) gametime.Elapsed.Totalseconds); 

     }
}


public class Game
{
     public void Initialize() { Components.Add(new TimerManager(this);}
     public Update()
     {
          if (HasToShowCard(out card)) 
          {
              Timer.Create(1, () => card.Show());
          }
     }
}   
Blau
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0
using System.Timers;
.
.
.    
public class Game1 : Microsoft.Xna.Framework.Game
{
    GraphicsDeviceManager graphics;
    SpriteBatch spriteBatch;
    Timer t = new Timer(1000);
    //The number is the interval in miliseconds

    public Game1()
    {
        graphics = new GraphicsDeviceManager(this);
        Content.RootDirectory = "Content";
        t.Elapsed += new ElapsedEventHandler(t_Elapsed);
        t.Enabled = true;
    }

    void t_Elapsed(object sender, ElapsedEventArgs e)
    {
        //code
    }

.
.
.
}

I copied some of the bits of code to show the positioning of the added code... Also, after typing "t.Elapsed +=" press TAB twice, to create the event handler. If you want to stop the timer, set the "Enabled" property to false. ('t' is a bad variable name)

NBcode
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  • Is System.Timers.Timer available in the compact framework? Might be worth letting the OP know he's sacrificing Xbox and phone support by using it.. – MattDavey Aug 23 '11 at 08:04
  • Hmm.. I don't know if it is.. but I can't comment on his original question to notify him. (If you see this, and want Xbox or phone support, use the suggestion by Andrew Russel – NBcode Aug 23 '11 at 08:45
  • Eventhough the OP asked for timers, it really isnt the best solution in game development. – TJHeuvel Aug 23 '11 at 09:07