Introduction to singleton mode

The singleton pattern

Reexamine the singleton pattern .
Singleton mode is the simplest design model , When we write a game management class GameManager when , We want only one instance of this class in memory , Save this instance through the static members of the class

With unity The inherited monobehavior Class GameManager Class, for example , You only need to save an instance of this class by saving a static member variable , Every time you want to generate a new GameManager Class time , If it already exists , Delete

Generic singleton pattern Singleton.cs

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
//  Generic singleton pattern   Give Way  MouseManager  and  GameManager  All inherit this class 
public class Singleton<T> : MonoBehaviour where T : Singleton<T>
{
    
    private static T instance;
    public static T Instance
    {
    
        get {
     return instance; }
    }
    protected virtual void Awake()
    {
    
        if (instance != null)
        {
    
            Destroy(gameObject);
        }
        else
        {
    
            instance = (T)this;
        }
    }
    public static bool IsInitialized
    {
    
        get {
     return instance != null; }
    }
    protected virtual void OnDestory()
    {
    
        if (instance == this)
        {
    
            instance = null;
        }
    }
}