unity事件相关整理

1.原生事件

监听：

触发：

回调：

可带参数，参考：https://docs.unity3d.com/ScriptReference/Events.UnityEvent.html

2.委托

委托是一种特殊类型的对象。

委托类：

实际运用中可将各种委托都放到这里面来，方便统一查找。

上面委托类中有一个负责消息传递，我们用它来传递文本消息，操作如下：

运行输出：

3.事件自定义实现

以上原生事件和委托实现的事件，都会使用起来相对麻烦甚至冗余等等，管理起来也比较复杂，比如我们需要创建各种继承UnityEvent类的其他类，需要增加各种委托去区分处理等等。

为了更友好、更方便的实现事件管理，下面来介绍自定义实现方式：

目地：接口友好、使用方便、管理简单！

需求：注册事件addListener、派发事件dispatch、移除事件removeListener，等。

实现：提供一个单例事件中心的类EventCenter

使用：

结果：

EventCenter主要代码：

private Dictionary<object, Dictionary<string, List<Action<object, object>>>> frameEventMap = new Dictionary<object, Dictionary<string, List<Action<object, object>>>>();
    public void addListener(object target, string eventName, Action<object, object> handler)
    ｛
        Dictionary<string, List<Action<object, object>>> targetMap;
        List<Action<object, object>> handlerList;
        Debug.Log("addListener target:" + target + " , eventName:" + eventName);
        if (frameEventMap.ContainsKey(target) == false)
        ｛
            targetMap = new Dictionary<string, List<Action<object, object>>>();
            frameEventMap[target] = targetMap;
        ｝
        targetMap = frameEventMap[target];
        if (targetMap.ContainsKey(eventName) == false)
        ｛
            handlerList = new List<Action<object, object>>();
            targetMap[eventName] = handlerList;
        ｝
        handlerList = targetMap[eventName];
        if (getHandlerInfo(handlerList, handler) == null)
        ｛
            handlerList.Add(handler);
            Debug.Log("addListener ok");
        ｝
    ｝
    public void removeListener(object target, string eventName, Action<object,object> handler)
    ｛
        if (frameEventMap.ContainsKey(target) == false)
        ｛
            return;
        ｝
        Dictionary<string, List<Action<object, object>>> targetMap = frameEventMap[target];
        if (targetMap.ContainsKey(eventName) == false)
        ｛
            return;
        ｝
        List<Action<object, object>> handlerList = targetMap[eventName];
        Action<object,object> handlerListInfo = getHandlerInfo(handlerList, handler);
        if (handlerListInfo != null)
        ｛
            handlerList.Remove(handler);
            Debug.Log("removeListener target:" + target + ", eventName:" + eventName);
        ｝
    ｝
    public void dispatch(string eventName, object arg1 = null, object arg2 = null)
     ｛
         Dictionary<string,List<Action<object,object>>> targetMap;
         List<Action<object, object>> handlerList;
        foreach (var item in frameEventMap)
        ｛
            targetMap = item.Value;
            if (targetMap!=null && targetMap.ContainsKey(eventName))
            ｛
                handlerList = targetMap[eventName];
                if (handlerList != null)
                ｛
                    foreach (Action<object, object> testHandler in handlerList)
                    ｛
                        if (testHandler != null)
                        ｛
                            Debug.Log("dispatch ok,[eventName:" + eventName + ",arg1:" + arg1 + ",arg2:" + arg2 + "]");
                            testHandler.Invoke(arg1, arg2);
                        ｝
                    ｝
                ｝
            ｝
        ｝
     ｝
    private Action<object, object> getHandlerInfo(List<Action<object, object>> handlerList, Action<object, object> handler)
    ｛
        foreach (Action<object, object> testHandler in handlerList)
        ｛
            if (testHandler == handler)
            ｛
                return testHandler;
            ｝
        ｝
        return null;
    ｝