用來做揹包 商店的按頁翻頁功能，先上效果圖

其中，dragNum 表示的是 如果為3，便是滑動距離超過當前頁面寬度的百分之三十位成功

connect表示 scrollRect下connet的大小

然後是函式的初始化方法 這裡提供了兩個方法  一個是直接提供頁數 引數分別代表 總頁數，要顯示的頁數 以及切換到要顯示的頁數是否播放滑動動畫

以及當時用來做揹包、商店的方法2

和上面不用的是傳入的是物品的數量以及每頁顯示格子數量的vector2 是否需要改變connect的大小 （需要提前把connect的大小設定為一頁的大小）以及開啟時顯示的頁數

思路大致如下 繼承 IBeginDragHandler, IEndDragHandler兩個介面

在begin時將需要的兩個引數 scrollNeedMove 以及scrollTargetValue 置位預設值

在end時計算

具體程式碼如下

using UnityEngine;
using System.Collections;
using UnityEngine.UI;
using UnityEngine.EventSystems;
public class ScrollPageTool : MonoBehaviour, IBeginDragHandler, IEndDragHandler
{



    public Button pageLastButton;
    public Button pageNextButton;
    public Text pageNumText;
    public GridLayoutGroup itemConnect;
    [SerializeField]
    private bool buttonPageEnable;
    private int m_nowPage;//從0開始
    private int m_pageCount;
    /// <summary>
    /// 滑動距離超過一頁的 (m_dragNum*10)% 則滑動成功
    /// </summary>
    public int m_dragNum;
    private float m_pageAreaSize;
    private const float SCROLL_SMOOTH_TIME = 0.2F;
    private const float SCROLL_MOVE_SPEED = 1F;
    private float scrollMoveSpeed = 0f;
    private bool scrollNeedMove = false;
    private float scrollTargetValue;
    public ScrollRect scrollRect;

    private bool isRegistEvent = false;

    public bool SetButtonStatus
    {
        set
        {
            buttonPageEnable = value;
            pageLastButton.interactable = buttonPageEnable && pageLastButton.interactable;
            pageNextButton.interactable = buttonPageEnable && pageNextButton.interactable;
        }
    }
    public void InitManager(int _allItemNum, Vector2 pageItemSize, bool isNeedChangeSize = true, int pageNum = 0,bool isShowAnim=false)
    {
        RegistEvent();
        int _pageItemNum = (int)(pageItemSize.x * pageItemSize.y);
        m_pageCount = (_allItemNum / _pageItemNum) + ((_allItemNum % _pageItemNum == 0) ? 0 : 1);
        m_pageAreaSize = 1f / (m_pageCount - 1);
        ChangePage(pageNum);
        if (isNeedChangeSize)
            itemConnect.GetComponent<RectTransform>().sizeDelta = new Vector2((itemConnect.cellSize.x * pageItemSize.x + itemConnect.spacing.x * pageItemSize.x) * m_pageCount,
            itemConnect.padding.top + itemConnect.padding.bottom + itemConnect.cellSize.y * pageItemSize.y + (pageItemSize.y - 1) * itemConnect.spacing.y);
    }

    public void InitManager(int pageNum, int targetPage = 0, bool isShowAnim = false)
    {
        RegistEvent();
        m_pageCount = pageNum;
        ChangePage(targetPage, isShowAnim);
    }

    private void RegistEvent()
    {
        if (isRegistEvent)
            return;
        isRegistEvent = true;
        if (pageLastButton != null)
            pageLastButton.onClick.AddListener(delegate { Paging(-1); });
        if (pageNextButton != null)
            pageNextButton.onClick.AddListener(delegate { Paging(1); });
    }

    private void Paging(int num)
    {
        //maxNum-1,從0開始
        num = (num < 0) ? -1 : 1;
        int temp = Mathf.Clamp(m_nowPage + num, 0, m_pageCount - 1);
        if (m_nowPage == temp)
            return;
        ChangePage(temp);
    }
    void Update()
    {
        ScrollControl();
    }

    public int GetPageNum { get { return m_nowPage; } }
    //按頁翻動
    private void ScrollControl()
    {
        if (!scrollNeedMove)
            return;
        if (Mathf.Abs(scrollRect.horizontalNormalizedPosition - scrollTargetValue) < 0.01f)
        {
            scrollRect.horizontalNormalizedPosition = scrollTargetValue;
            scrollNeedMove = false;
            return;
        }
        scrollRect.horizontalNormalizedPosition = Mathf.SmoothDamp(scrollRect.horizontalNormalizedPosition, scrollTargetValue, ref scrollMoveSpeed, SCROLL_SMOOTH_TIME);
    }

    public void OnBeginDrag(PointerEventData eventData)
    {
        scrollNeedMove = false;
        scrollTargetValue = 0;
    }
    public void OnEndDrag(PointerEventData eventData)
    {
        int tempPage = m_nowPage;

        int num=(((scrollRect.horizontalNormalizedPosition - (m_nowPage * m_pageAreaSize))>=0)?1:-1);

        if(Mathf.Abs(scrollRect.horizontalNormalizedPosition - (m_nowPage * m_pageAreaSize))>= (m_pageAreaSize / 10f) * m_dragNum)
        {
            tempPage+=num;

        }
        ChangePage(tempPage);
    }

    public void ChangePage(int pageNum, bool isShowAnim = true)
    {
        if (pageNum >= m_pageCount)
            pageNum = m_pageCount - 1;
        if (pageNum < 0)
            pageNum = 0;

        m_nowPage = pageNum;
        ChangePageText(pageNum);
        if (isShowAnim)
        {
            scrollTargetValue = m_nowPage * m_pageAreaSize;
            scrollNeedMove = true;
            scrollMoveSpeed = 0;
        }
        else
        {
            scrollRect.horizontalNormalizedPosition = m_nowPage * m_pageAreaSize;
        }
        ChangePageText(m_nowPage);
    }

    public void ChangePageText(int num)
    {
        int maxPageTo0Start = m_pageCount - 1;
        m_nowPage = Mathf.Clamp(num, 0, maxPageTo0Start);

        if (pageNumText != null)
            pageNumText.text = (m_nowPage + 1).ToString() + "/" + m_pageCount.ToString();

        //only one page
        if (maxPageTo0Start == 0)
        {
            scrollRect.enabled = false;
            pageLastButton.interactable = false;
            pageNextButton.interactable = false;
            return;
        }
        else
        {
            pageLastButton.interactable = true;
            pageNextButton.interactable = true;
            scrollRect.enabled = true;
        }
        SetButtonStatus = buttonPageEnable;
        if (!buttonPageEnable)
            return;

        if (m_nowPage == 0 && pageLastButton.interactable)
            pageLastButton.interactable = false;
        if (m_nowPage >= maxPageTo0Start && pageNextButton.interactable)
            pageNextButton.interactable = false;
        if (m_nowPage > 0 && (!pageLastButton.interactable))
            pageLastButton.interactable = true;
        if (m_nowPage < maxPageTo0Start && (!pageNextButton.interactable))
            pageNextButton.interactable = true;


    }
}