GHZSDKXR/RokidSDK/com.rokid.ar.mrc/Runtime/Scripts/Utility/Singleton.cs

using UnityEngine;
using System.Collections;
using System;
namespace Rokid.MRC
{
    public abstract class Singleton<T> where T : class, new()
    {
        private static T instance;

        public static T Instance
        {
            get
            {
                if(instance == null)
                {
                    instance = new T();
                }
                return instance;
            }
        }

        //private Singleton()
        //{

        //}

        public virtual void Init()
        {

        }

        public virtual void OnDestroy()
        {

        }
    }

    public class UnitySingleton<T> : MonoBehaviour
        where T : Component
    {
        private static T _instance;
        public static T Instance
        {
            get
            {
                if(_instance == null)
                {
                    _instance = FindObjectOfType(typeof(T)) as T;
                    if(_instance == null)
                    {
                        GameObject obj = new GameObject();
                        //obj.hideFlags = HideFlags.HideAndDontSave;
                        _instance = (T)obj.AddComponent(typeof(T));
                    }
                }
                return _instance;
            }
        }

        public virtual void Awake()
        {
            DontDestroyOnLoad(this.gameObject);

            if(_instance == null)
            {
                _instance = this as T;
            }
        }
    }
}