Unity（三十三）：ScrollView嵌套

效果

布局

脚本

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

public class CustomScrollRect : ScrollRect
{
    private CustomScrollRect _parent;

    private enum Direction
    {
        Horizontal,
        Vertical
    }

    // 滑动方向
    private Direction _direction;
    // 操作方向
    private Direction _beginDragDirection;

    protected override void Awake()
    {
        base.Awake();
        if (transform.parent)
        {
            _parent = transform.parent.GetComponentInParent<CustomScrollRect>();
        }
        _direction = horizontal ? Direction.Horizontal : Direction.Vertical;
    }
    
    // 开始拖动时已选择控制柄
    public override void OnBeginDrag(PointerEventData eventData)
    {
        if (_parent)
        {
            _beginDragDirection = Mathf.Abs(eventData.delta.x) > Mathf.Abs(eventData.delta.y) ? Direction.Horizontal : Direction.Vertical;
            if (_beginDragDirection != _direction)
            {
                // 当前操作方向不等于滑动方向，将事件传给父对象
                ExecuteEvents.Execute(_parent.gameObject, eventData, ExecuteEvents.beginDragHandler);
                return;
            }
        }
        base.OnBeginDrag(eventData);
    }

    // 拖动内容时的处理
    public override void OnDrag(PointerEventData eventData)
    {
        if (_parent)
        {
            if (_beginDragDirection != _direction)
            {
                // 当前操作方向不等于滑动方向，将事件传给父对象
                ExecuteEvents.Execute(_parent.gameObject, eventData, ExecuteEvents.dragHandler);
                return;
            }
        }
        base.OnDrag(eventData);
    }

    // 完成内容拖动时的处理
    public override void OnEndDrag(PointerEventData eventData)
    {
        if (_parent)
        {
            if (_beginDragDirection != _direction)
            {
                // 当前操作方向不等于滑动方向，将事件传给父对象
                ExecuteEvents.Execute(_parent.gameObject, eventData, ExecuteEvents.endDragHandler);
                return;
            }
        }
        base.OnEndDrag(eventData);
    }

    public override void OnScroll(PointerEventData data)
    {
        if (_parent)
        {
            if (_beginDragDirection != _direction)
            {
                // 当前操作方向不等于滑动方向，将事件传给父对象
                ExecuteEvents.Execute(_parent.gameObject, data, ExecuteEvents.scrollHandler);
                return;
            }
        }
        base.OnScroll(data);
    }
}