GameObjectPooler

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

public class GameObjectPooler
{
    public int maxPoolSize = 5;

    private GameObject poolObject;
    private List<GameObject> pooledObjects;

    /// <summary>
    /// Creates a new instance of GameObjectPooler and
    /// Instantiates the maximum number of GameObjects.
    /// </summary>
    /// <param name="t">Original copy of GameObject to pool.</param>
    public GameObjectPooler(GameObject newPooledObject)
    {
        poolObject = newPooledObject;

        for (int i = 0; i < maxPoolSize; i++)
        {
            GameObject newObject = Object.Instantiate(poolObject);
            newObject.gameObject.SetActive(false);
            pooledObjects.Add(newObject);
        }
    }

    /// <summary>
    /// Retrieves the first inactive pooled GameObject and
    /// returns it.
    /// </summary>
    /// <returns>First inactive pooled GameObject.</returns>
    public GameObject GetPooledObject()
    {
        for (int i = 0; i < pooledObjects.Count; i++)
        {
            if (!pooledObjects[i].gameObject.activeInHierarchy)
            {
                return pooledObjects[i];
            }
        }

        return null;
    }

    /// <summary>
    /// Returns an active pooled GameObject to inactive state.
    /// </summary>
    /// <param name="toPoolObject">Pooled GameObject to be returned.</param>
    public void ReturnPooledObject(GameObject toPoolObject)
    {
        toPoolObject.gameObject.SetActive(false);
    }
}