然後直接新建指令碼
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.UI;
using UnityEngine.EventSystems;

/// <summary>
/// 指令碼掛在ScrollView上
/// </summary>
public class Clander : MonoBehaviour ,IDragHandler{
    //滾動檢視
    public ScrollRect year;
    //滑鼠點選和釋放時候的座標  通過eventData獲取
 

    Vector3 pressPos;
    Vector3 releasePos;

    //拖拽的距離
    float distance;
    //滾動檢視content下物體的高
    float itemHeight;
    //年份
    int middleYear = 1949;
    //選擇的年份
    string selectYeay;
    //拖拽觸發
    public void OnDrag(PointerEventData eventData)
    {
        //  ContentItemMove(eventData.delta);
        // print(eventData.delta);  delta是一個動態的值
 

        pressPos =  eventData.pressPosition;
        releasePos = eventData.position;
        //求距離
        distance = Mathf.Abs(releasePos.y - pressPos.y);
        
       ContentItemMove(eventData.delta);

        YearChange();
    }

    // Use this for initialization
    void Start () {

        itemHeight
 
 = year.content.GetChild(0).GetComponent<RectTransform>().rect.height;

        year.content.GetChild(2).GetComponent<Text>().text = middleYear.ToString();
    }
	
	// Update is called once per frame
	void Update () {
        
    }
    /// <summary>
    /// 用來移動檢視
    /// </summary>
    /// <param name="move"></param>
    void ContentItemMove(Vector2 move)
    {
        //當移動距離大於一個item的時候
        if (distance > itemHeight) 
        {
            for (int i = 0; i < year.content.childCount; i++)
            {
                //上移
                if (releasePos.y >pressPos.y)
                {
                    //
                    year.content.GetChild(i).GetComponent<RectTransform>().anchoredPosition += new Vector2(0 ,move.y );
                }
                else //下移
                {
                    year.content.GetChild(i).GetComponent<RectTransform>().anchoredPosition += new Vector2(0,move.y);
                }
            }
        }
    }
    //無限滾動和改變年份（有Bug）,思路就是在滾動檢視中有四個item   顯示介面中最中間的item是基準，  也就是content中索引是2的子物體   這個索引是2的物體是一直在改變的
    void YearChange()
    {
        for (int i = 0;i<year.content.childCount;i++)
        {
            //處於索引2的時候，字型是白色  其餘的是黑色  用來突出選擇的年份
            if (year.content.GetChild(i).GetComponent<RectTransform>().anchoredPosition.y > -15 && year.content.GetChild(i).GetComponent<RectTransform>().anchoredPosition.y < 15)
            {
                year.content.GetChild(i).GetComponent<Text>().color = Color.white;
                //把選擇的年份賦值到變數中，一遍獲取
                selectYeay = year.content.GetChild(i).GetComponent<Text>().text;
            }
            else
            {
                year.content.GetChild(i).GetComponent<Text>().color = Color.black;
            }
            
        }
        //在拖拽的過程中，作為基準的索引2的相對位置的y值大於15的時候（整個item的高是30）   把最上面的item移動到最下面
        if (year.content.GetChild(2).GetComponent<RectTransform>().anchoredPosition.y > 15)
        {
            //更改預設年份
            middleYear = middleYear + 1;
            //改所i有item的索引
            year.content.GetChild(0).SetAsLastSibling();
            //移動 放到最後一個item的下面
            year.content.GetChild(0).GetComponent<RectTransform>().anchoredPosition = year.content.GetChild(3).GetComponent<RectTransform>().anchoredPosition - new Vector2(0, itemHeight);
            //更改顯示的年份
            year.content.GetChild(0).GetComponent<Text>().text = (middleYear + 2).ToString();
        }
        else if (year.content.GetChild(2).GetComponent<RectTransform>().anchoredPosition.y < -45)
        {
            middleYear = middleYear - 1;
            year.content.GetChild(3).SetAsFirstSibling();
            year.content.GetChild(3).GetComponent<RectTransform>().anchoredPosition = year.content.GetChild(0).GetComponent<RectTransform>().anchoredPosition + new Vector2(0, itemHeight);
            year.content.GetChild(3).GetComponent<Text>().text = (middleYear - 1).ToString();
        }
    }
    public void ConfirmYear()
    {
        print("當前選擇年份" + selectYeay);
    }
}