U3D C# 实现AS3事件机制

　　写了很多年的AS3，最近接触U3D感觉事件机制没AS3的爽。咬紧牙关一鼓作气 基于C# 的委托实现了一版。废话不多说上干货。

EventDispatcher代码如下：

using UnityEngine;
using System.Collections;
using System;
using System.Collections.Generic;
/**
* EventDispatcher 类是可调度事件的所有类的基类
* @author 回眸笑苍生
**/
public abstract class EventDispatcher : MonoBehaviour
{
//定义委托
public delegate void EventDelegate(EventObject evt);

protected Dictionary<String,List<EventDelegate>> captureListeners = null;

protected Dictionary<String,List<EventDelegate>> bubbleListeners = null;

protected EventDispatcher _parent;

public void addEventListener(String types, EventDelegate listener, bool useCapture = false, int priority = 0, bool useWeakReference=false)
{
Dictionary<String,List<EventDelegate>> listeners = null;

if (listener == null)
{
throw new ArgumentNullException("Parameter listener must be non-null.");
}
if (useCapture)
{
if (captureListeners == null) captureListeners = new Dictionary<string, List<EventDelegate>>();
listeners = captureListeners;
}
else
{
if (bubbleListeners == null) bubbleListeners = new Dictionary<string, List<EventDelegate>>();
listeners = bubbleListeners;
}
List<EventDelegate> vector = null;
if (listeners.ContainsKey (types))
{
vector = listeners[types];
}
if (vector == null)
{
vector = new List<EventDelegate>();
listeners.Add(types, vector);
}
if (vector.IndexOf(listener) < 0)
{
vector.Add(listener);
}
}

public void removeEventListener(String types, EventDelegate listener, bool useCapture = false)
{
if (listener == null)
{
throw new ArgumentNullException("Parameter listener must be non-null.");
}
Dictionary<string, List<EventDelegate>> listeners = useCapture ? captureListeners : bubbleListeners;
if (listeners != null)
{
List<EventDelegate> vector = listeners [types];
if (vector != null)
{
int i = vector.IndexOf(listener);
if (i >= 0)
{
int length = vector.Count;
for(int j = i+1;j < length;j++,i++)
{
vector[i] = vector[j];
}

listeners.Remove(types);

foreach (KeyValuePair<String, List<EventDelegate>> o in listeners)
{
if(o.Key == null)
{
if (listeners == captureListeners)
{
captureListeners = null;
}
else
{
bubbleListeners = null;
}
}
}
}
}
}

}

public bool hasEventListener(String types)
{
return (captureListeners != null && captureListeners.ContainsKey(types)) || (bubbleListeners != null && bubbleListeners.ContainsKey(types));
}

public bool willTrigger(String types)
{
for (EventDispatcher _object = this; _object != null; _object = _object._parent)
{
if ((_object.captureListeners != null && _object.captureListeners.ContainsKey(types)) ||( _object.bubbleListeners != null && _object.bubbleListeners.ContainsKey(types)))
return true;
}
return false;
}

public bool dispatchEvent(EventObject evt)
{
if (evt == null)
{
throw new ArgumentNullException("Parameter EventObject must be non-null.");
}
EventObject event3D = evt;
if (event3D != null)
{
event3D.setTarget = this;
}
List<EventDispatcher> branch = new List<EventDispatcher> ();
int branchLength = 0;
EventDispatcher _object;
int i, j = 0;
int length;
List<EventDelegate> vector;
List<EventDelegate> functions;
for (_object = this; _object !=null; _object=_object._parent)
{
branch.Add(_object);
branchLength++;
}
for (i = branchLength - 1; i > 0; i--)
{
_object = branch[i];
if (event3D != null)
{
event3D.setCurrentTarget = _object;
event3D.setEventPhase = EventPhase.CAPTURING_PHASE;
}
if (_object.captureListeners != null)
{
vector = _object.captureListeners[evt.types];
if (vector != null)
{
length = vector.Count;
functions = new List<EventDelegate>();
for (j = 0; j < length; j++) functions[j] = vector[j];
for (j = 0; j < length; j++) (functions[j] as EventDelegate)(evt);
}
}
}
if (event3D != null)
{
event3D.setEventPhase = EventPhase.AT_TARGET;
}
for (i = 0; i < branchLength; i++) {
_object = branch[i];
if (event3D != null) {
event3D.setCurrentTarget = _object;
if (i > 0) {
event3D.setEventPhase = EventPhase.BUBBLING_PHASE;
}
}
if (_object.bubbleListeners != null) {
vector = _object.bubbleListeners[evt.types];
if (vector != null) {
length = vector.Count;
functions = new List<EventDelegate>();
for (j = 0; j < length; j++) functions.Add(vector[j]);
for (j = 0; j < length; j++) (functions[j] as EventDelegate)(evt);
}
}
if (!event3D.bubbles) break;
}
return true;
}

}

EventPhase代码如下：

using UnityEngine;
using System.Collections;
/**
* EventPhase 类可为 Event 类的 eventPhase 属性提供值。
* @author 回眸笑苍生
**/
public class EventPhase
{

public const int CAPTURING_PHASE = 1;

public const int AT_TARGET = 2;

public const int BUBBLING_PHASE = 3;
}

EventObject代码如下：

using UnityEngine;
using System.Collections;
using System;
/**
* EventObject 类作为创建 Event 对象的基类，当发生事件时，Event 对象将作为参数传递给事件侦听器。
* @author 回眸笑苍生
**/
public class EventObject
{
public const String ACTIVATE = "activate";
public const String ADDED = "added";
public const String ADDED_TO_STAGE = "addedToStage";
public const String CANCEL = "cancel";
public const String CHANGE = "change";
public const String CLEAR = "clear";
public const String CLOSE = "close";
public const String CLOSING = "closing";
public const String COMPLETE = "complete";
public const String CONNECT = "connect";
public const String OPEN = "open";

private EventDispatcher _target;
private int _eventPhase;
private EventDispatcher _currentTarget;
private bool _bubbles;
private bool _cancelable;
private String _types;

public EventObject(String types, bool bubbles=false, bool cancelable=false)
{
this._types = types;
this._bubbles= bubbles;
this._cancelable = cancelable;
}

public EventDispatcher target
{
get { return _target; }
}

internal EventDispatcher setTarget
{
set { _target = value; }
}

public EventDispatcher currentTarget
{
get { return _currentTarget; }
}

internal EventDispatcher setCurrentTarget
{
set { _currentTarget = value; }
}

public int eventPhase
{
get { return _eventPhase; }
}

internal int setEventPhase
{
set { _eventPhase = value; }
}

public bool bubbles
{
get { return _bubbles; }
}

public String types
{
get { return _types; }
}

public bool cancelable
{
get { return _cancelable; }
}
}

在使用过程中 大家可以把 U3D中新建Class 默认继承的基类 换成 EventDispatcher 这样一来就拥有了和AS3一样的 事件机制了。

有什么Bug 欢迎大家多多指教。