}
void InitPageArray()
{
    foreach (Transform item in uUIGrid)
    {
        items.Add(item);
    }
    pageCount = uUIGrid.childCount;
    pageArray = new float[pageCount];
    for (int i = 0; i < pageCount; i++)
    {
        pageArray[i] = (1f / (pageCount - 1)) * i;
    }
}

// Update is called once per frame
void Update()
{
    if (!isDrag)
    {
        scrollRect.horizontalNormalizedPosition = Mathf.Lerp(scrollRect.horizontalNormalizedPosition, targetPagePosition, scrollSpeed * Time.deltaTime);
    }
}

public void OnBeginDrag(PointerEventData eventData)
{
    isDrag = true;
}

public void OnEndDrag(PointerEventData eventData)
{
    isDrag = false;
    float posX = scrollRect.horizontalNormalizedPosition;
    int index = 0;
    float offset = Math.Abs(pageArray[index] - posX);
    for (int i = 1; i < pageArray.Length; i++)
    {
        float _offset = Math.Abs(pageArray[i] - posX);
        if (_offset < offset)
        {
            index = i;
            offset = _offset;
        }
    }
    targetPagePosition = pageArray[index];
    currentPage = index;
}
//想左移动一个元素
public void ToLeft()
{
    if (currentPage > 0)
    {
        currentPage = currentPage - 1;
        targetPagePosition = pageArray[currentPage];
    }
}
//想右移动一个元素
public void ToRight()
{
    if (currentPage < pageCount - 1)
    {
        currentPage = currentPage + 1;
        targetPagePosition = pageArray[currentPage];
    }
}

public int GetCurrentPageIndex()
{
    return currentPage;
}
public void SetCurrentPageIndex(int index)
{
    currentPage = index;
    targetPagePosition = pageArray[currentPage];
}
public int GetTotalPages()
{
    return pageCount;
}