02.继承MonoBehaviour的单例模式基类

一、基本写法

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class NewBehaviourScript : MonoBehaviour
{
    private static NewBehaviourScript instance;
    public static NewBehaviourScript GetInstance()
    {
        return instance;
    }
    private void Awake()
    {
        instance = this;//脚本挂载在游戏对象上，运行时赋值
    }
}

二、改进后

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class SingletonMono<T> : MonoBehaviour where T:MonoBehaviour
{
    // Start is called before the first frame update
    private static T instance;
    public static T GetInstance()
    {
        return instance;
    }
    protected virtual void Awake()
    {
        instance = this as T;
    }
}

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class NewBehaviourScript : SingletonMono<NewBehaviourScript>
{
    private void Start()
    {
        NewBehaviourScript.GetInstance();
    }

    protected override void Awake()
    {
        base.Awake();
    }
}

继承了MonoBehaviour的单例模式对象，需要我们自己保证它的唯一性，不要重复挂载一个脚本，否则它的唯一性就会被破坏。

三、自动创建对象并挂载脚本的方法，不用手动挂载脚本，防止重复挂载

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class SingletonAutoMono<T> : MonoBehaviour where T : MonoBehaviour
{
    // Start is called before the first frame update
    private static T instance;
    public static T GetInstance()
    {
        if (instance == null)
        {
            GameObject obj = new GameObject();
            //设置对象的名字为脚本名
            obj.name = typeof(T).ToString();
            GameObject.DontDestroyOnLoad(obj);
            instance = obj.AddComponent<T>();
        }
            
        return instance;
    }
    
}

测试脚本

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class NewBehaviourScript : SingletonAutoMono<NewBehaviourScript>
{
    public void Test()
    {
        Debug.Log(NewBehaviourScript.GetInstance().name);
    }
}

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class Test : MonoBehaviour
{
    // Start is called before the first frame update
    void Start()
    {
        NewBehaviourScript.GetInstance().Test();
    }

}