StandaloneInputModule
+ ctor()+ AddListener(UnityAction)+ RemoveListener(UnityAction);+ Invoke()
PointerInputModule
AxisEventData
+ moveDir+ moveVector
BaseInputModule
+ Process() : 每帧调用
IDe/SelectHandler
IPointerXXXHandler
PhysicsRayCaster
IDragXXXHandler
BaseRayCaster
IEventSystemHandler
BaseEventData
+ currentInputModule.+ selectedObject+ used
TouchInputModule
EventSystem
+ currentInputModule + static current : EventSystem+ (current/first/last)SelectedGameObject: GameObject
+ RaycastAll(PointerEventData List);
UnityEvent分为泛型和非泛型两种，用法各有不同，不同模版参数的UnityEvent对应相应的UnityAction
UnityEventBase
+ GetPersistentEventCount() : int+ GetPersistentMethodName(int) : string+ GetPersistentTarget(int) ： Object+ RemoveAllListeners()
Physics2DRayCaster
需要绑定在同一个GameObject上
PointerEventData
+ button+ delta+ scrollDelta+ pointerCurrentRaycast+ position+ worldPosition
