【Unity】UGUI ScrollView 分页 单次拖拽滑动一页

一，新建ScrollView ，目录结构如图：

二，在content下编辑需要显示的关卡内容，这里设置为一页显示一个button集合，14个button为一整页，一次只显示一页内容：

下面上代码：

using UnityEngine;
using System.Collections;
using UnityEngine.UI;
using UnityEngine.EventSystems;
using System.Collections.Generic;
using System;
public class ScrollRectHelper : MonoBehaviour, IBeginDragHandler, IEndDragHandler
{
    private float smooting;                          //滑动速度
    private float normalSpeed = 5;
    private float highSpeed = 100;
    private int pageCount = 1;                           //每页显示的项目
    public GameObject listItem;                    
    private ScrollRect sRect;
    private float pageIndex;                      //总页数
    private bool isDrag = false;                                //是否拖拽结束
    private List<float> listPageValue = new List<float> { 0 };  //总页数索引比列 0-1

    private float m_targetPos = 0;                                //滑动的目标位置
    //public float TargetPos
    //{
    //    set { m_targetPos = value; }
    //}
    private float nowindex = 0;                                 //当前位置索引
    private float beginDragPos;
    private float endDragPos;
    private float sensitivity = 0.05f;                          //灵敏度
    void Awake()
    {
        sRect = this.GetComponent<ScrollRect>();
        ListPageValueInit();
        smooting = normalSpeed;
        //StartCoroutine(ToTarPage(1));
    }

    //每页比例
    void ListPageValueInit()
    {
        pageIndex = (listItem.transform.childCount / pageCount) - 1;
        if (listItem != null && listItem.transform.childCount != 0)
        {
            for (float i = 1; i <= pageIndex; i++)
            {
                listPageValue.Add((i / pageIndex));
            }
        }
    }
    public IEnumerator ToTarPage(int tarIndex)
    {
        m_targetPos = tarIndex;
        smooting = highSpeed;
        yield return null;
        smooting = normalSpeed;
    }
    void Update()
    {
        if (!isDrag)
            sRect.horizontalNormalizedPosition = Mathf.Lerp(sRect.horizontalNormalizedPosition, m_targetPos, Time.deltaTime * smooting);
    }
    /// <summary>
    /// 拖动开始
    /// </summary>
    /// <param name="eventData"></param>
    public void OnBeginDrag(PointerEventData eventData)
    {
        isDrag = true;
        beginDragPos = sRect.horizontalNormalizedPosition;
    }
    /// <summary>
    /// 拖拽结束
    /// </summary>
    /// <param name="eventData"></param>
    public void OnEndDrag(PointerEventData eventData)
    {
        isDrag = false;
        endDragPos = sRect.horizontalNormalizedPosition; //获取拖动的值
        endDragPos = endDragPos > beginDragPos ? endDragPos + sensitivity : endDragPos - sensitivity;
        int index = 0;
        float offset = Mathf.Abs(listPageValue[index] - endDragPos);    //拖动的绝对值
        for (int i = 1; i < listPageValue.Count; i++)
        {
            float temp = Mathf.Abs(endDragPos - listPageValue[i]);
            if (temp < offset)
            {
                index = i;
                offset = temp;
            }
        }
        m_targetPos = listPageValue[index];
        nowindex = index;
    }

    public void BtnLeftGo()
    {
        nowindex = Mathf.Clamp(nowindex - 1, 0, pageIndex);
        m_targetPos = listPageValue[Convert.ToInt32(nowindex)];
    }

    public void BtnRightGo()
    {
        nowindex = Mathf.Clamp(nowindex + 1, 0, pageIndex);
        m_targetPos = listPageValue[Convert.ToInt32(nowindex)];
    }
}