EventTrigger

描述

接收来自 EventSystem 的事件，并为每个事件调用已注册的函数。

EventTrigger 可用来指定您想为每个 EventSystem 事件调用的函数。 您可以将多个函数分配给单个事件，每当 EventTrigger 收到该事件时，都会按照这些函数的提供顺序调用它们。

注意：将此组件附加到游戏对象将导致该对象拦截所有事件，并且所有事件都不会传播到父对象。

您可以通过两种方式拦截事件：一是扩展 EventTrigger，并覆盖您想拦截的事件的函数；如以下示例所示：

using UnityEngine;
using UnityEngine.EventSystems;

public class EventTriggerExample : EventTrigger
{
    public override void OnBeginDrag(PointerEventData data)
    {
        Debug.Log("OnBeginDrag called.");
    }

    public override void OnCancel(BaseEventData data)
    {
        Debug.Log("OnCancel called.");
    }

    public override void OnDeselect(BaseEventData data)
    {
        Debug.Log("OnDeselect called.");
    }

    public override void OnDrag(PointerEventData data)
    {
        Debug.Log("OnDrag called.");
    }

    public override void OnDrop(PointerEventData data)
    {
        Debug.Log("OnDrop called.");
    }

    public override void OnEndDrag(PointerEventData data)
    {
        Debug.Log("OnEndDrag called.");
    }

    public override void OnInitializePotentialDrag(PointerEventData data)
    {
        Debug.Log("OnInitializePotentialDrag called.");
    }

    public override void OnMove(AxisEventData data)
    {
        Debug.Log("OnMove called.");
    }

    public override void OnPointerClick(PointerEventData data)
    {
        Debug.Log("OnPointerClick called.");
    }

    public override void OnPointerDown(PointerEventData data)
    {
        Debug.Log("OnPointerDown called.");
    }

    public override void OnPointerEnter(PointerEventData data)
    {
        Debug.Log("OnPointerEnter called.");
    }

    public override void OnPointerExit(PointerEventData data)
    {
        Debug.Log("OnPointerExit called.");
    }

    public override void OnPointerUp(PointerEventData data)
    {
        Debug.Log("OnPointerUp called.");
    }

    public override void OnScroll(PointerEventData data)
    {
        Debug.Log("OnScroll called.");
    }

    public override void OnSelect(BaseEventData data)
    {
        Debug.Log("OnSelect called.");
    }

    public override void OnSubmit(BaseEventData data)
    {
        Debug.Log("OnSubmit called.");
    }

    public override void OnUpdateSelected(BaseEventData data)
    {
        Debug.Log("OnUpdateSelected called.");
    }
}

二是指定单个委托：

using UnityEngine;
using UnityEngine.EventSystems;


public class EventTriggerDelegateExample : MonoBehaviour
{
    void Start()
    {
        EventTrigger trigger = GetComponent<EventTrigger>();
        EventTrigger.Entry entry = new EventTrigger.Entry();
        entry.eventID = EventTriggerType.PointerDown;
        entry.callback.AddListener((data) => { OnPointerDownDelegate((PointerEventData)data); });
        trigger.triggers.Add(entry);
    }

    public void OnPointerDownDelegate(PointerEventData data)
    {
        Debug.Log("OnPointerDownDelegate called.");
    }
}

变量

公共函数

继承的成员