Unity3D：如何在没有 spawner 单例的情况下进行对象池

Question

通常，如果你使用对象池，你会像this 视频中那样制作一个单例。 看了this 的视频后，我才发现单身狗有多乱。有没有其他方法可以在不使用单例的情况下进行对象池？我想改用事件。

Answer 1

您需要将池保存在一个非单例类中，并根据您的事件处理您的游戏对象池。 关于用事件调用它们，“我想使用事件”不是一个非常具体的问题。您需要将事件设置为监听（方法订阅）并在代码中调用它们应该发生的任何地方，这就是调用方法。我建议如果您对此不清楚，请尝试使用统一事件（Update 中的 OnTriggerEnter、if(Input.GetMouseButtonDown(0)) 等），直到您深入研究主题以理解它们并让您拥有 c# 事件或需要时UnityEvents。

找到两个模板脚本，一个池和一个事件处理程序来处理场景中的对象。您可以在一个空场景中使用您各自的两个游戏对象来附加它们，以及您想要在池中的对象，分别按“空格”和“A”从池中创建并返回到池中。

泳池管理员：

using System.Collections.Generic;
using UnityEngine;

public class PoolManager : MonoBehaviour
{
    private Queue<GameObject> objPool;
    private Queue<GameObject> activeObj;
    private int poolSize = 10;
    public GameObject objPrefab;

    void Start()
    {
        //queues init
        objPool = new Queue<GameObject>();  
        activeObj = new Queue<GameObject>();
        //pool init
        for (int i = 0; i < poolSize; i++) 
        {
            GameObject newObj = Instantiate(objPrefab);
            objPool.Enqueue(newObj);   
            newObj.SetActive(false);    
        }
    }

    public GameObject GetRandomActiveGO() {
        GameObject lastActive = default;
        if (activeObj.Count > 0)
            lastActive = activeObj.Dequeue();
        else {
            Debug.LogError("Active object queue is empty");
        }
        return lastActive;
    }

    //get from pool
    public GameObject GetObjFromPool(Vector3 newPosition, Quaternion newRotation)
    {
        GameObject newObject = objPool.Dequeue();
        newObject.SetActive(true);
        newObject.transform.SetPositionAndRotation(newPosition, newRotation);

        //keep actives to be retrieved
        activeObj.Enqueue(newObject);
        return newObject;
    }

    //return to pool
    public void ReturnObjToPool(GameObject go)
    {
        go.SetActive(false);
        objPool.Enqueue(go);
    }
}

事件处理程序：

using UnityEngine;

public class EventHandler : MonoBehaviour
{
    public delegate GameObject OnSpacePressed(Vector3 newPosition, Quaternion newRotation);
    public OnSpacePressed onSpacePressed;

    public delegate void OnAKeyPressed(GameObject go);
    public OnAKeyPressed onAKeyPressed;

    public PoolManager poolManager;

    void Start()
    {
        onSpacePressed = poolManager.GetObjFromPool;
        onAKeyPressed = poolManager.ReturnObjToPool;
    }

    void Update()
    {
        if (Input.GetKeyDown(KeyCode.Space))
        {
            onSpacePressed?.Invoke(new Vector3(0, 0, 0), Quaternion.identity);
        }

        //here I get a random active, however this would be called in the specific objects remove circumstances, 
        //so you should have a reference to that specific gameobje when rerunrning it to the pool.
        if (Input.GetKeyDown(KeyCode.A))
        { 
            GameObject go = poolManager.GetRandomActiveGO();
            onAKeyPressed?.Invoke(go);
        }
    }
}

编辑：单例模式

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class Singleton<T> : MonoBehaviour where T : MonoBehaviour
{
    protected static T _instance;
    public static T instance
    {
        get
        {
            if (_instance == null)
            {
                _instance = GameObject.FindObjectOfType<T>();
                if (_instance == null)
                {
                    _instance = new GameObject(typeof(T).Name).AddComponent<T>();
                }

            }
            return _instance;
        }
    }
}