1 files changed, 368 insertions, 0 deletions
diff --git a/Assets/uGUI-2017.1/UnityEngine.UI/EventSystem/EventHandler/ExecuteEvents.cs b/Assets/uGUI-2017.1/UnityEngine.UI/EventSystem/EventHandler/ExecuteEvents.cs
new file mode 100644
index 0000000..a749ce8
--- /dev/null
+++ b/Assets/uGUI-2017.1/UnityEngine.UI/EventSystem/EventHandler/ExecuteEvents.cs
@@ -0,0 +1,368 @@
+using System;
+using System.Collections.Generic;
+using UnityEngine.UI;
+
+namespace UnityEngine.EventSystems
+{
+    // 最关键的类，调用gameobject对应的回调函数
+    public static class ExecuteEvents
+    {
+        public delegate void EventFunction<T1>(T1 handler, BaseEventData eventData);
+
+        public static T ValidateEventData<T>(BaseEventData data) where T : class
+        {
+            if ((data as T) == null)
+                throw new ArgumentException(String.Format("Invalid type: {0} passed to event expecting {1}", data.GetType(), typeof(T)));
+            return data as T;
+        }
+
+        private static readonly EventFunction<IPointerEnterHandler> s_PointerEnterHandler = Execute;
+
+        private static void Execute(IPointerEnterHandler handler, BaseEventData eventData)
+        {
+            handler.OnPointerEnter(ValidateEventData<PointerEventData>(eventData));
+        }
+
+        private static readonly EventFunction<IPointerExitHandler> s_PointerExitHandler = Execute;
+
+        private static void Execute(IPointerExitHandler handler, BaseEventData eventData)
+        {
+            handler.OnPointerExit(ValidateEventData<PointerEventData>(eventData));
+        }
+
+        private static readonly EventFunction<IPointerDownHandler> s_PointerDownHandler = Execute;
+
+        private static void Execute(IPointerDownHandler handler, BaseEventData eventData)
+        {
+            handler.OnPointerDown(ValidateEventData<PointerEventData>(eventData));
+        }
+
+        private static readonly EventFunction<IPointerUpHandler> s_PointerUpHandler = Execute;
+
+        private static void Execute(IPointerUpHandler handler, BaseEventData eventData)
+        {
+            handler.OnPointerUp(ValidateEventData<PointerEventData>(eventData));
+        }
+
+        private static readonly EventFunction<IPointerClickHandler> s_PointerClickHandler = Execute;
+
+        private static void Execute(IPointerClickHandler handler, BaseEventData eventData)
+        {
+            handler.OnPointerClick(ValidateEventData<PointerEventData>(eventData));
+        }
+
+        private static readonly EventFunction<IInitializePotentialDragHandler> s_InitializePotentialDragHandler = Execute;
+
+        private static void Execute(IInitializePotentialDragHandler handler, BaseEventData eventData)
+        {
+            handler.OnInitializePotentialDrag(ValidateEventData<PointerEventData>(eventData));
+        }
+
+        private static readonly EventFunction<IBeginDragHandler> s_BeginDragHandler = Execute;
+
+        private static void Execute(IBeginDragHandler handler, BaseEventData eventData)
+        {
+            handler.OnBeginDrag(ValidateEventData<PointerEventData>(eventData));
+        }
+
+        private static readonly EventFunction<IDragHandler> s_DragHandler = Execute;
+
+        private static void Execute(IDragHandler handler, BaseEventData eventData)
+        {
+            handler.OnDrag(ValidateEventData<PointerEventData>(eventData));
+        }
+
+        private static readonly EventFunction<IEndDragHandler> s_EndDragHandler = Execute;
+
+        private static void Execute(IEndDragHandler handler, BaseEventData eventData)
+        {
+            handler.OnEndDrag(ValidateEventData<PointerEventData>(eventData));
+        }
+
+        private static readonly EventFunction<IDropHandler> s_DropHandler = Execute;
+
+        private static void Execute(IDropHandler handler, BaseEventData eventData)
+        {
+            handler.OnDrop(ValidateEventData<PointerEventData>(eventData));
+        }
+
+        private static readonly EventFunction<IScrollHandler> s_ScrollHandler = Execute;
+
+        private static void Execute(IScrollHandler handler, BaseEventData eventData)
+        {
+            handler.OnScroll(ValidateEventData<PointerEventData>(eventData));
+        }
+
+        private static readonly EventFunction<IUpdateSelectedHandler> s_UpdateSelectedHandler = Execute;
+
+        private static void Execute(IUpdateSelectedHandler handler, BaseEventData eventData)
+        {
+            handler.OnUpdateSelected(eventData);
+        }
+
+        private static readonly EventFunction<ISelectHandler> s_SelectHandler = Execute;
+
+        private static void Execute(ISelectHandler handler, BaseEventData eventData)
+        {
+            handler.OnSelect(eventData);
+        }
+
+        private static readonly EventFunction<IDeselectHandler> s_DeselectHandler = Execute;
+
+        private static void Execute(IDeselectHandler handler, BaseEventData eventData)
+        {
+            handler.OnDeselect(eventData);
+        }
+
+        private static readonly EventFunction<IMoveHandler> s_MoveHandler = Execute;
+
+        private static void Execute(IMoveHandler handler, BaseEventData eventData)
+        {
+            handler.OnMove(ValidateEventData<AxisEventData>(eventData));
+        }
+
+        private static readonly EventFunction<ISubmitHandler> s_SubmitHandler = Execute;
+
+        private static void Execute(ISubmitHandler handler, BaseEventData eventData)
+        {
+            handler.OnSubmit(eventData);
+        }
+
+        private static readonly EventFunction<ICancelHandler> s_CancelHandler = Execute;
+
+        private static void Execute(ICancelHandler handler, BaseEventData eventData)
+        {
+            handler.OnCancel(eventData);
+        }
+
+        public static EventFunction<IPointerEnterHandler> pointerEnterHandler
+        {
+            get { return s_PointerEnterHandler; }
+        }
+
+        public static EventFunction<IPointerExitHandler> pointerExitHandler
+        {
+            get { return s_PointerExitHandler; }
+        }
+
+        public static EventFunction<IPointerDownHandler> pointerDownHandler
+        {
+            get { return s_PointerDownHandler; }
+        }
+
+        public static EventFunction<IPointerUpHandler> pointerUpHandler
+        {
+            get { return s_PointerUpHandler; }
+        }
+
+        public static EventFunction<IPointerClickHandler> pointerClickHandler
+        {
+            get { return s_PointerClickHandler; }
+        }
+
+        public static EventFunction<IInitializePotentialDragHandler> initializePotentialDrag
+        {
+            get { return s_InitializePotentialDragHandler; }
+        }
+
+        public static EventFunction<IBeginDragHandler> beginDragHandler
+        {
+            get { return s_BeginDragHandler; }
+        }
+
+        public static EventFunction<IDragHandler> dragHandler
+        {
+            get { return s_DragHandler; }
+        }
+
+        public static EventFunction<IEndDragHandler> endDragHandler
+        {
+            get { return s_EndDragHandler; }
+        }
+
+        public static EventFunction<IDropHandler> dropHandler
+        {
+            get { return s_DropHandler; }
+        }
+
+        public static EventFunction<IScrollHandler> scrollHandler
+        {
+            get { return s_ScrollHandler; }
+        }
+
+        public static EventFunction<IUpdateSelectedHandler> updateSelectedHandler
+        {
+            get { return s_UpdateSelectedHandler; }
+        }
+
+        public static EventFunction<ISelectHandler> selectHandler
+        {
+            get { return s_SelectHandler; }
+        }
+
+        public static EventFunction<IDeselectHandler> deselectHandler
+        {
+            get { return s_DeselectHandler; }
+        }
+
+        public static EventFunction<IMoveHandler> moveHandler
+        {
+            get { return s_MoveHandler; }
+        }
+
+        public static EventFunction<ISubmitHandler> submitHandler
+        {
+            get { return s_SubmitHandler; }
+        }
+
+        public static EventFunction<ICancelHandler> cancelHandler
+        {
+            get { return s_CancelHandler; }
+        }
+
+        private static void GetEventChain(GameObject root, IList<Transform> eventChain)
+        {
+            eventChain.Clear();
+            if (root == null)
+                return;
+
+            var t = root.transform;
+            while (t != null)
+            {
+                eventChain.Add(t);
+                t = t.parent;
+            }
+        }
+
+        //IEventSystemHandler是所有接口的基类
+        private static readonly ObjectPool<List<IEventSystemHandler>> s_HandlerListPool = new ObjectPool<List<IEventSystemHandler>>(null, l => l.Clear());
+
+        // 向target gameobject发送一个事件，对每个实现了T接口的类执行functor方法（就是接口中定义的回调）
+        public static bool Execute<T>(GameObject target, BaseEventData eventData, EventFunction<T> functor) where T : IEventSystemHandler
+        {
+            var internalHandlers = s_HandlerListPool.Get();
+            GetEventList<T>(target, internalHandlers);
+            //  if (s_InternalHandlers.Count > 0)
+            //      Debug.Log("Executinng " + typeof (T) + " on " + target);
+
+            // 拿到实现了T接口的组件，调用对应的方法
+
+            for (var i = 0; i < internalHandlers.Count; i++)
+            {
+                T arg;
+                try
+                {
+                    arg = (T)internalHandlers[i];
+                }
+                catch (Exception e)
+                {
+                    var temp = internalHandlers[i];
+                    Debug.LogException(new Exception(string.Format("Type {0} expected {1} received.", typeof(T).Name, temp.GetType().Name), e));
+                    continue;
+                }
+
+                try
+                {
+                    functor(arg, eventData);
+                }
+                catch (Exception e)
+                {
+                    Debug.LogException(e);
+                }
+            }
+
+            var handlerCount = internalHandlers.Count;
+            s_HandlerListPool.Release(internalHandlers);
+            return handlerCount > 0;
+        }
+
+        /// <summary>
+        /// Execute the specified event on the first game object underneath the current touch.
+        /// </summary>
+        private static readonly List<Transform> s_InternalTransformList = new List<Transform>(30);
+
+        public static GameObject ExecuteHierarchy<T>(GameObject root, BaseEventData eventData, EventFunction<T> callbackFunction) where T : IEventSystemHandler
+        {
+            GetEventChain(root, s_InternalTransformList);
+
+            for (var i = 0; i < s_InternalTransformList.Count; i++)
+            {
+                var transform = s_InternalTransformList[i];
+                if (Execute(transform.gameObject, eventData, callbackFunction))
+                    return transform.gameObject;
+            }
+            return null;
+        }
+
+        //c component是否匹配类型T且是否被激活
+        private static bool ShouldSendToComponent<T>(Component component) where T : IEventSystemHandler
+        {
+            var valid = component is T;
+            if (!valid)
+                return false;
+
+            var behaviour = component as Behaviour;
+            if (behaviour != null)
+                return behaviour.isActiveAndEnabled;
+            return true;
+        }
+
+        /// <summary>
+        /// Get the specified object's event event.
+        /// </summary>
+        private static void GetEventList<T>(GameObject go, IList<IEventSystemHandler> results) where T : IEventSystemHandler
+        {
+            // Debug.LogWarning("GetEventList<" + typeof(T).Name + ">");
+            if (results == null)
+                throw new ArgumentException("Results array is null", "results");
+
+            if (go == null || !go.activeInHierarchy)
+                return;
+
+            var components = ListPool<Component>.Get();
+            go.GetComponents(components);
+            // 遍历所有的组件，找到匹配类型T的
+            for (var i = 0; i < components.Count; i++)
+            {
+                // 如果不匹配类型T，跳过这个
+                if (!ShouldSendToComponent<T>(components[i]))
+                    continue;
+
+                // Debug.Log(string.Format("{2} found! On {0}.{1}", go, s_GetComponentsScratch[i].GetType(), typeof(T)));
+                results.Add(components[i] as IEventSystemHandler);
+            }
+            ListPool<Component>.Release(components);
+            // Debug.LogWarning("end GetEventList<" + typeof(T).Name + ">");
+        }
+
+        /// <summary>
+        /// Whether the specified game object will be able to handle the specified event.
+        /// </summary>
+        public static bool CanHandleEvent<T>(GameObject go) where T : IEventSystemHandler
+        {
+            var internalHandlers = s_HandlerListPool.Get();
+            GetEventList<T>(go, internalHandlers);
+            var handlerCount = internalHandlers.Count;
+            s_HandlerListPool.Release(internalHandlers);
+            return handlerCount != 0;
+        }
+
+        /// <summary>
+        /// Bubble the specified event on the game object, figuring out which object will actually receive the event.
+        /// </summary>
+        public static GameObject GetEventHandler<T>(GameObject root) where T : IEventSystemHandler
+        {
+            if (root == null)
+                return null;
+
+            Transform t = root.transform;
+            while (t != null)
+            {
+                if (CanHandleEvent<T>(t.gameObject))
+                    return t.gameObject;
+                t = t.parent;
+            }
+            return null;
+        }
+    }
+}