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

public class CustomDropdown : Dropdown
{
    public override void OnPointerClick(PointerEventData eventData)
    {
        // 调用基类的 OnPointerClick 方法
        base.OnPointerClick(eventData);
        // 在此处添加你想要的逻辑，这将在 Dropdown 展开时执行
        Debug.Log("Dropdown is showing");

        var rect = this.transform.Find("Dropdown List/Viewport/Content").GetComponent<RectTransform>();
        var pos = rect.localPosition;
        pos.y = rect.sizeDelta.y * ((float)this.value / this.options.Count);
        rect.localPosition = pos;
    }
}