UGUI解決嵌套使用多個ScrollRect時的Drag拖動沖突問題

很簡單，直接看代碼：

using UnityEngine.UI;
using UnityEngine.EventSystems;
using UnityEngine;

/// <summary>
/// 解決嵌套使用ScrollRect時的Drag沖突問題。請將該腳本放置到內層ScrollRect上(外層的ScrollRect的Drag事件會被內層的攔截)
/// </summary>
public class NestedScrollRect : MonoBehaviour, IBeginDragHandler, IDragHandler, IEndDragHandler
{
    /// <summary>
    /// 外層被攔截需要正常拖動的ScrollRect，可不指定，默認在父對象中找
    /// </summary>
    public ScrollRect anotherScrollRect;
    /// <summary>
    /// 當前的ScrollRect（本腳本所放置的物體上）的拖動方向默認為上下拖動，否則為左右拖動型
    /// </summary>
    public bool thisIsUpAndDown = true;

    private ScrollRect thisScrollRect;

    void Awake ()
    {
        thisScrollRect = GetComponent<ScrollRect> ();
        if (anotherScrollRect == null)
            anotherScrollRect = GetComponentsInParent<ScrollRect> ()[1];
    }

    public void OnBeginDrag (PointerEventData eventData)
    {
        anotherScrollRect.OnBeginDrag (eventData);
    }

    public void OnDrag (PointerEventData eventData)
    {
        anotherScrollRect.OnDrag (eventData);
        float angle = Vector2.Angle (eventData.delta, Vector2.up);
        //判斷拖動方向，防止水平與垂直方向同時響應導致的拖動時整個界面都會動
        if (angle > 45f && angle < 135f)
        {
            thisScrollRect.enabled = !thisIsUpAndDown;
            anotherScrollRect.enabled = thisIsUpAndDown;
        }
        else
        {
            anotherScrollRect.enabled = !thisIsUpAndDown;
            thisScrollRect.enabled = thisIsUpAndDown;
        }
    }

    public void OnEndDrag (PointerEventData eventData)
    {
        anotherScrollRect.OnEndDrag (eventData);
        anotherScrollRect.enabled = true;
        thisScrollRect.enabled = true;
    }
}