有沒有辦法用派生類填充基類單例實例？

Question

我有一個基礎播放器類，其中包含一個Singleton聲明。 我想用derivedClass填充baseClass.Instance var，如果可能的話。

我當前的方法是，當derivedClass“喚醒”時，它會嘗試設置Instance = this; 我也試過調用base.Init（），然后設置Instance = this; 在base.Init（）方法中。 這將設置Instance！= null，但Instance！= derivedClass也是如此。

// Current approach
public abstract class BasePlayer : Entity, IPlayerBase
{
    // Singleton instance, to be populated by the derived class
    private static BasePlayer _i = null;
    private static object _lock = new object();
    private static bool _disposing = false; // Check if we're in the process of disposing this singleton

    public static BasePlayer Instance
    {
        get
        {
            if (_disposing)
                return null;
            else
                return _i;
        }

        protected set
        {
            lock (_lock)
            {
                if(_i == null && !_disposing)
                    _i = value;
            }
        }
    }

    protected void Init()
    {
        if (Instance == null)
        {
            Instance = this;
        }
        else if (Instance != null)
        {
            Active = false;
            Destroy(this.gameObject);
        }

        if (Instance == this)
        {
            Debug.Log("Successfully set BaseClass");
            ...
        }
    }
}

// Current approach
public class FPSPlayer : BasePlayer
{
    void OnEnable()
    {
        base.Init();
    }
}

// Also tried
public class FPSPlayer : BasePlayer
{
    void OnEnable()
    {
        if (Instance == null)
        {
            Instance = this;
        }
        else if (Instance != null)
        {
            Active = false;
            Destroy(this.gameObject);
        }

        if (Instance == this)
        {
            ...
        }
    }
}

Answer 1

使用工廠類返回單例實例。 例如

public static class PlayerFactory
{
   private static BasePlayer _instance;

   public static BasePlayer Instance 
   {
      get { return _instance; }
      protected set { _instance = value; }
   } 
}

它應該接受來自BasePlayer的任何對象作為單個實例。