RaindropViewer/Assets/Plugins/ObjectPool/Singleton.cs

using UnityEngine;

public class Singleton<T> : MonoBehaviour where T : Singleton<T>
{
	public static T Instance
	{
		get
		{
			if (instance == null)
			{
				T[] managers = Object.FindObjectsOfType(typeof(T)) as T[];
				if (managers.Length != 0)
				{
					if (managers.Length == 1)
					{
						instance = managers[0];
						instance.gameObject.name = typeof(T).Name;
						return instance;
					}
					else
					{
						Debug.LogError("Class " + typeof(T).Name + " exists multiple times in violation of singleton pattern. Destroying all copies");
						foreach (T manager in managers)
						{
							Destroy(manager.gameObject);
						}
					}
				}
				var go = new GameObject(typeof(T).Name, typeof(T));
				instance = go.GetComponent<T>();
				DontDestroyOnLoad(go);
			}
			return instance;
		}
		set
		{
			instance = value as T;
		}
	}
	private static T instance;
}