观察者模式之通用消息发布与订阅

观察者模式：当对象间存在一对多关系时，则使用观察者模式。比如，当一个对象被修改时，则会自动通知依赖它的对象。观察者模式属于行为型模式。
主要解决：一个对象状态改变给其他对象通知的问题，而且要考虑到易用和低耦合，保证高度的协作。

TestCommonEvent.cs

using System.Collections.Generic;

public class TestCommonEvent : System.IDisposable
{
    public delegate void OnActionHandler(object obj);
    public Dictionary<ushort, LinkedList<OnActionHandler>> dic = new Dictionary<ushort, LinkedList<OnActionHandler>>();

    /// <summary>
    /// 添加监听
    /// </summary>
    /// <param name="key"></param>
    /// <param name="actionEvent"></param>
    public void AddEventListener(ushort key, OnActionHandler actionEvent)
    {
        dic.TryGetValue(key, out LinkedList<OnActionHandler> list);
        if (list == null)
        {
            list = new LinkedList<OnActionHandler>();
            dic[key] = list;
        }
        list.AddLast(actionEvent);
    }

    /// <summary>
    /// 移除监听
    /// </summary>
    /// <param name="key"></param>
    /// <param name="actionEvent"></param>
    public void RemoveEventListener(ushort key, OnActionHandler actionEvent)
    {
        if (dic.TryGetValue(key, out LinkedList<OnActionHandler> list))
        {
            list.Remove(actionEvent);
            if (list.Count == 0)
            {
                dic.Remove(key);
            }
        }
    }

    /// <summary>
    /// 派发
    /// </summary>
    /// <param name="key"></param>
    /// <param name="obj"></param>
    public void Dispatch(ushort key, object obj)
    {
        if (dic.TryGetValue(key, out LinkedList<OnActionHandler> list))
        {
            for (var v = list.First; v != null; v = v.Next)
            {
                v.Value?.Invoke(obj);
            }
        }
    }

    public void Dispose()
    {
        dic.Clear();
    }
}

TestEventManager.cs

public class TestEventManager : System.IDisposable
{
    public TestCommonEvent commonEvent;
    public TestEventManager()
    {
        commonEvent = new TestCommonEvent();
    }

    public void Init()
    {
    }

    public void Dispose()
    {
        commonEvent.Dispose();
    }
}

 

测试用例：

建3个物体 分别挂上对应的脚本：

 Xiaozhang.cs

using UnityEngine;

public class Xiaozhang : MonoBehaviour
{
    void Update()
    {
        if (Input.GetKeyDown(KeyCode.F))
        {
            string times = "16:30";
            if (TestGameEntry.EventMgr != null)
            {
                TestGameEntry.EventMgr.commonEvent.Dispatch(TestCommonEventId.xiaozhangFangXue, times);
            }
        }
    }
}

  Xiaohong.cs

using UnityEngine;

public class Xiaohong : MonoBehaviour
{
    void Start()
    {
        if (TestGameEntry.EventMgr != null)
        {
            TestGameEntry.EventMgr.commonEvent.AddEventListener(TestCommonEventId.xiaozhangFangXue, Xiaozhangfangxue);
        }
    }

    private void Xiaozhangfangxue(object obj)
    {
        Debug.LogError("小张放学了,我去找他玩");
    }

    private void OnDestroy()
    {
        TestGameEntry.EventMgr.commonEvent.RemoveEventListener(TestCommonEventId.xiaozhangFangXue, Xiaozhangfangxue);
    }
}

mama.cs

using UnityEngine;

public class Mama : MonoBehaviour
{
    void Start()
    {
        if (TestGameEntry.EventMgr != null)
        {
            TestGameEntry.EventMgr.commonEvent.AddEventListener(TestCommonEventId.xiaozhangFangXue, Xiaozhangfangxue);
        }
    }
    private void Xiaozhangfangxue(object obj)
    {
        Debug.LogError("小张" + obj.ToString() + "点放学了,我得去接孩子了");
    }

    private void OnDestroy()
    {
        TestGameEntry.EventMgr.commonEvent.RemoveEventListener(TestCommonEventId.xiaozhangFangXue, Xiaozhangfangxue);
    }
}

TestCommonEventId.cs

public class TestCommonEventId
{
    public const ushort xiaozhangFangXue = 10001;
}

 按键 ”F“ 进行测试