NGUI无限滑动

[code]csharpcode：

using UnityEngine;
using System.Collections;
using System.Collections.Generic;

/// <summary>
/// 扩展NGUIScroll滑动类，需要继承该类进行开发
/// </summary>
public abstract  class NGUIDynamicScrollBase : MonoBehaviour
{

    //每个列表项数据初始化
    abstract protected void ResetItemData(GameObject go, int index);
    public UIPanel panel;
    public UIGrid grid;
    //目标prefab
    public GameObject prefab;
    //宽度
    public int cellHeight = 60;
    //高度
    public int cellWidth = 700;
    //裁剪区的高度
    private float m_height;
    //裁剪区的宽度
    private int m_maxLine;
    //当前滑动的列表
    protected GameObject[] m_cellList;
    //当前需要滑动的列表总数
    private int m_dataListCount;
    //自定义滑动
    private UICustomScrollView mDrag;
    //最后一次的滑动位置
    private float lastY = -1;
    private Vector3 defaultVec;

    // Use this for initialization
    protected void BaseOnEnable()
    {
        GetConfiguration();
    }

    // Update is called once per frame
    protected void BaseUpdate()
    {
        if (panel.transform.localPosition.y != lastY)
        {
            Validate();
            lastY = panel.transform.localPosition.y;
        }
    }
    //设置当前列表中的
    protected int DataListCount
    {
        get { return m_dataListCount; }

        set{
            m_dataListCount = value;
            
            AddItem(m_dataListCount);
            PlayMoveAnimation(m_cellList);
        }
    }



    #region private Functions

    //初始化配置数据
    private void GetConfiguration()
    {
        //物体默认位置
        defaultVec = new Vector3(0, cellHeight, 0);
        //裁剪区域的高度
        m_height = panel.height;
        //裁剪区域中最多显示的cellItem数量
        m_maxLine = Mathf.CeilToInt(m_height / cellHeight) + 1;
        //初始化CellList
        m_cellList = new GameObject[m_maxLine];
        //创建Item，默认为不可显示状态
        CreateItem();
    }
    //创建Item
    private void CreateItem()
    {
        for (int i = 0; i < m_maxLine; i++)
        {
            GameObject go = null;
            go = (GameObject)Instantiate(prefab);
            go.gameObject.SetActive(false);
            go.GetComponent<UICustomDragScrollView>().scrollView = panel.GetComponent<UICustomScrollView>();
            AddChild(grid.gameObject, go);
            go.transform.localScale = Vector3.one;
            go.transform.localPosition = new Vector3(cellWidth * AllScale.ResolutionScale, -i * cellHeight, 0);
            m_cellList[i] = go;
            go.gameObject.SetActive(false);
        }
    }


    //验证当前区域中的需要显示的CellItem
    private void Validate()
    {
        Vector3 position = panel.transform.localPosition;

        float _ver = Mathf.Max(position.y, 0);

        int startIndex = Mathf.FloorToInt(_ver / cellHeight);

        int endIndex = Mathf.Min(DataListCount, startIndex + m_maxLine);

        GameObject cell;
        int index = 0;
        for (int i = startIndex; i < startIndex + m_maxLine; i++)
        {
            cell = m_cellList[index];

            if (i < endIndex)
            {
                //开始渲染
                cell.gameObject.SetActive(true);
                //重新填充数据
                ResetItemData(cell, i);
                //改变位置
                cell.transform.localPosition = new Vector3(cell.transform.localPosition.x, i * -cellHeight, 0);
                cell.name = "Item_" + index;
            }
            else
            {
                cell.transform.localPosition = defaultVec;
              //  cell.gameObject.SetActive(false);
            }

            index++;
        }
    }

    //重新计算包围合的大小
    private void UpdateBounds(int count)
    {
        Vector3 vMin = new Vector3();
        vMin.x = -grid.transform.localPosition.x;
        vMin.y = grid.transform.localPosition.y - count * cellHeight;
        vMin.z = grid.transform.localPosition.z;
        Bounds b = new Bounds(vMin, Vector3.one);
        b.Encapsulate(grid.transform.localPosition);
        if (mDrag == null) mDrag = panel.GetComponent<UICustomScrollView>();
        mDrag.bounds = b;
        mDrag.UpdateScrollbars(true);
        mDrag.RestrictWithinBounds(true);
    }


    //根据新的数量来重新绘制
    private void AddItem(int count)
    {
        Validate();
        UpdateBounds(count);
    }
    
    //增加孩子节点
    void AddChild(GameObject parent, GameObject go)
    {
        Transform t = go.transform;
        t.parent = parent.transform;
        t.localPosition = Vector3.zero;
        t.localRotation = Quaternion.identity;
        t.localScale = Vector3.one;
        go.layer = parent.layer;
    }

    //播放开始加载的位移动画
    void PlayMoveAnimation(GameObject[] list)
    {
        Vector3 to;
        Vector3 from;
        for (int i = 0; i < list.Length; i++)
        {
            from = list[i].transform.localPosition;
            from = new Vector3(cellWidth*AllScale.ResolutionScale, from.y, 0);
            to = new Vector3(0, from.y, 0);
            list[i].transform.localPosition = from;
            TweenPosition tp = TweenPosition.Begin(list[i], 0.8f, to);
            tp.delay = 0.1f;
            tp.from = from;
            tp.to = to;
            tp.duration = (i + 2) * 0.1f;
            tp.method = UITweener.Method.EaseIn;
        }
    }
    #endregion


   
}