Unity3D 中DontDestroyOnLoad单例模式的使用DDOL

墨蓝 2023-07-24 03:22 13阅读 0赞

## 1. 继承于MonoBehaviour（不随着场景切换而销毁） ##

基类代码：

![复制代码][aHR0cHM6Ly9jb21tb24uY25ibG9ncy5jb20vaW1hZ2VzL2NvcHljb2RlLmdpZg]

1 using System.Collections;
     2 using System.Collections.Generic;
     3 using UnityEngine;
     4 
     5 /// <summary>
     6 /// 单例模式基类，继承于 MonoBehaviour，不随场景切换而销毁
     7 /// 在场景中新建空物体 DDOL，挂载 T 类继承 DDOLSingleton<T> 即可
     8 /// </summary>
     9 /// <typeparam name="T"></typeparam>
    10 public abstract class DDOLSingleton<T> : MonoBehaviour where T : DDOLSingleton<T>
    11 {
    12     protected static T _instance = null;
    13 
    14     public static T Instance
    15     {
    16         get
    17         {
    18             if (null == _instance)
    19             {
    20                 GameObject go = GameObject.Find("DDOL");
    21                 if (null == go)
    22                 {
    23                     go = new GameObject("DDOL");
    24                     DontDestroyOnLoad(go);
    25                 }
    26                 _instance = go.GetComponent<T>();
    27                 if (null == _instance)
    28                 {
    29                     _instance = go.AddComponent<T>();
    30                 }
    31             }
    32             return _instance;
    33         }
    34     }
    35 }

![复制代码][aHR0cHM6Ly9jb21tb24uY25ibG9ncy5jb20vaW1hZ2VzL2NvcHljb2RlLmdpZg]

测试：

新建空实体 DDOL，挂载脚本 GameManage。

新建一个按钮，实现加载下一场景功能，测试是否随场景销毁而销毁。

Hierarchy :

![format_png][]

GameManage 代码：

![复制代码][aHR0cHM6Ly9jb21tb24uY25ibG9ncy5jb20vaW1hZ2VzL2NvcHljb2RlLmdpZg]

1 using System.Collections.Generic;
     2 using UnityEngine;
     3 
     4 /// <summary>
     5 /// 单例
     6 /// </summary>
     7 public class GameManage : DDOLSingleton<GameManage> {
     8     public void TestMethod()
     9     {
    10         Debug.Log("GameManage");
    11     }
    12 }

![复制代码][aHR0cHM6Ly9jb21tb24uY25ibG9ncy5jb20vaW1hZ2VzL2NvcHljb2RlLmdpZg]

测试代码：

![复制代码][aHR0cHM6Ly9jb21tb24uY25ibG9ncy5jb20vaW1hZ2VzL2NvcHljb2RlLmdpZg]

1 /// <summary>
     2 /// 测试单例
     3 /// </summary>
     4 public class Test : MonoBehaviour {
     5 
     6     // Use this for initialization
     7     void Start () {
     8         GameManage.Instance.TestMethod();
     9     }
    10     
    11     // Update is called once per frame
    12     void Update () {
    13         
    14     }
    15 
    16     public void OnBtnClick()
    17     {
    18         SceneManager.LoadScene(1);
    19     }
    20 }

![复制代码][aHR0cHM6Ly9jb21tb24uY25ibG9ncy5jb20vaW1hZ2VzL2NvcHljb2RlLmdpZg]

效果图：

![format_png 1][]

## 2. 不继承于MonoBehaviour（随着场景切换而销毁） ##

基类代码：

![复制代码][aHR0cHM6Ly9jb21tb24uY25ibG9ncy5jb20vaW1hZ2VzL2NvcHljb2RlLmdpZg]

1 /// <summary>
     2 /// 单例模式基类，不继承于 MonoBehaviour，随场景切换而销毁
     3 /// 挂载 T 类继承 DDOLSingleton<T>，重载 Init 函数即可
     4 /// </summary>
     5 /// <typeparam name="T"></typeparam>
     6 public abstract class Singleton<T> where T : class, new()
     7 {
     8     protected static T _instance = null;
     9 
    10     public static T Instance
    11     {
    12         get
    13         {
    14             if (null == _instance)
    15             {
    16                 _instance = new T();
    17             }
    18             return _instance;
    19         }
    20     }
    21 
    22     protected Singleton()
    23     {
    24         if (null != _instance)
    25         {
    26             Debug.LogError("This " + typeof(T).ToString() + " Singleton Instance is not null !!!");
    27         }
    28         Init();
    29     }
    30 
    31     public virtual void Init()
    32     {
    33 
    34     }
    35 }

![复制代码][aHR0cHM6Ly9jb21tb24uY25ibG9ncy5jb20vaW1hZ2VzL2NvcHljb2RlLmdpZg]

此时 GameManage 代码修改为：

![复制代码][aHR0cHM6Ly9jb21tb24uY25ibG9ncy5jb20vaW1hZ2VzL2NvcHljb2RlLmdpZg]

1 /// <summary>
     2 /// 测试 Singleton
     3 /// </summary>
     4 public class GameManage : Singleton<GameManage> {
     5     public override void Init()
     6     {
     7         base.Init();
     8     }
     9 
    10     public void TestMethod()
    11     {
    12         Debug.Log("GameManage");
    13     }
    14 }

![复制代码][aHR0cHM6Ly9jb21tb24uY25ibG9ncy5jb20vaW1hZ2VzL2NvcHljb2RlLmdpZg]

[aHR0cHM6Ly9jb21tb24uY25ibG9ncy5jb20vaW1hZ2VzL2NvcHljb2RlLmdpZg]: /images/20230528/5a1f5c93dda54b85a64c51d7fb9951db.png
[format_png]: /images/20230528/9df6db349f72409295307211fe9917c2.png
[format_png 1]: /images/20230528/c23ec4c8fb0d421e82cb8d445533b545.png