Unity 圆形循环复用滚动列表

一.在上一篇垂直循环复用滚动列表的基础上，扩展延申了圆形循环复用滚动列表。实现此效果需要导入垂直循环复用滚动列表里面的类。

1.基础类

using System.Collections.Generic;
using UnityEngine;
using UnityEngine.UI;
using UnityEngine.EventSystems;
using UnityEngine.UIElements;/// <summary>
/// 环形的网格布局；
/// 让子对象摆成一个环形；
/// </summary>
public class CricleGrid : MonoBehaviour
{/// <summary>/// 是否是自动刷新模式，否则的话需要手动调用刷新；/// </summary>public bool IsAutoRefresh = true;/// <summary>/// 是否发生过改变；/// </summary>private bool IsChanged = false;/// <summary>/// 上一次检查的数量；/// </summary>int LastCheckCount = 0;/// <summary>/// Update每帧调用一次/// </summary>void Update(){检查是否需要自动刷新；if (!IsAutoRefresh)return;if (!IsChanged){//检测子物体有没有被改变；GetChidList();int length = ListRect.Count;if (length != LastCheckCount){LastCheckCount = length;IsChanged = true;}//此时刷新大小和位置；if (IsChanged)ResetSizeAndPos();}elseRefreshAll();}private void OnValidate(){//编辑器下每一次更改需要实时刷新；RefreshAll();}/// <summary>/// 全部刷新；/// </summary>public void RefreshAll(){GetChidList();ResetSizeAndPos();}/// <summary>/// 当下激活的Rect；/// </summary>public List<RectTransform> ListRect = new List<RectTransform>(4);List<RectTransform> tempListRect = new List<RectTransform>(4);/// <summary>/// 获取父节点为本身的子对象/// </summary>void GetChidList(){ListRect.Clear();GetComponentsInChildren(false, tempListRect);int length = tempListRect.Count;for (int i = 0; i < length; i++){var r = tempListRect[i];if (r.transform.parent != transform) continue;ListRect.Add(r);}}/// <summary>/// 网格大小；/// </summary>public Vector2 CellSize = new Vector2();/// <summary>/// 半径；/// </summary>public float Radius = 1;/// <summary>/// 起始角度；/// </summary>[Range(0f, 360f)][SerializeField]float m_StartAngle = 30;/// <summary>/// 起始角度；/// </summary>public float StartAngle{get { return m_StartAngle; }set{m_StartAngle = value;IsChanged = true;}}/// <summary>/// 间隔角度；/// </summary>[Range(0f, 360f)][SerializeField]float m_Angle = 30;/// <summary>/// 间隔角度；/// </summary>public float Angle{get { return m_Angle; }set{m_Angle = value;IsChanged = true;}}public Dictionary<int, CricleScrollItemPosData> itemPosDic = new();public List<CricleScrollItemPosData> itemPosList = new();/// <summary>/// 重新将字节点设置大小；/// </summary>public void ResetSizeAndPos(){int length = ListRect.Count;for (int i = 0; i < length; i++){var tran = ListRect[i];tran.sizeDelta = CellSize;var v = GerCurPosByIndex(i);tran.anchoredPosition = new Vector2(v.x,v.y);tran.localEulerAngles = new Vector3(0,0, v.z);}}/// <summary>/// 返回第几个子对象应该所在的相对位置；/// </summary>public Vector3 GerCurPosByIndex(int index){//1、先计算间隔角度：(弧度制)float totalAngle = Mathf.Deg2Rad * (index * Angle + m_StartAngle);//2、计算位置Vector3 Pos = new Vector2(Radius * Mathf.Cos(totalAngle), Mathf.Sin(totalAngle) * Radius);Pos.z = index * Angle + m_StartAngle + 180;return Pos;}public ScrollRect scrollRect;public List<object> list = new();public GameObject item;private List<CustomScrollItemMono> scrollTestItems = new();private int startIndex;private int endIndex;private int showItemCount = 10;private void InitItemsPos() {int n = (int)(360f / Angle);for (int i = 0; i < list.Count; i++){var v = GerCurPosByIndex(i);CricleScrollItemPosData data = new CricleScrollItemPosData();data.AnchoredPosition = new Vector3(v.x, v.y);data.LocalEulerAngles = new Vector3(0, 0, v.z);itemPosDic.Add(i, data);itemPosList.Add(data);//if (i < n)//{//    var v = GerCurPosByIndex(i);//    CricleScrollItemPosData data = new CricleScrollItemPosData();//    data.AnchoredPosition = new Vector3(v.x, v.y);//    data.LocalEulerAngles = new Vector3(0, 0, v.z);//    itemPosDic.Add(i, data);//    itemPosList.Add(data);//}//else //{//    int temp = i % n;//    int m = (i + 1) / n;//    CricleScrollItemPosData d = new CricleScrollItemPosData();//    d.AnchoredPosition = itemPosDic[temp].AnchoredPosition;//    d.LocalEulerAngles.z += itemPosDic[temp].LocalEulerAngles.z + 360 * m;//    itemPosDic.Add(i, d);//    itemPosList.Add(d);//}}Debug.Log($"InitItemsPos ");}private void InitShowItems(){for (int i = 0; i < showItemCount; i++){GameObject obj = Instantiate(item, transform);obj.transform.name = i.ToString();obj.SetActive(true);CustomScrollItemMono testItem = obj.GetComponent<CustomScrollItemMono>();testItem.Init(i, list[i]);scrollTestItems.Add(testItem);}item.SetActive(false);}private float eulerAnglersZ;private float preA = 1;public ScrollRect ScrollRect;private RectTransform Content;/// <summary>/// 用这个初始化/// </summary>void Start(){for (int i = 0; i < 100; i++){list.Add(new ScrollTestData() { ID = i });}Content = ScrollRect.content;Content.sizeDelta = new Vector2(500, (100 * Angle / 360 + StartAngle % 360 / 360f) * 2 * Mathf.PI * Radius);InitItemsPos();InitShowItems();RefreshAll();}private void Awake(){scrollRect.horizontal = false;scrollRect.vertical = true;scrollRect.onValueChanged.AddListener((value) =>{float offset = Mathf.Abs(preA - value.y);float aa = (offset) * ((100 - 6) * Angle);if (scrollRect.velocity.y > 0) //手指上滑 {transform.localEulerAngles -= new Vector3(0,0, aa);eulerAnglersZ += aa;}else if (scrollRect.velocity.y < 0)//手指下滑 {transform.localEulerAngles += new Vector3(0, 0, aa);eulerAnglersZ -= aa;}preA = value.y;for (int i = startIndex; i < itemPosList.Count; i++){if (i + 1 < itemPosList.Count){if (scrollRect.velocity.y > 0)//手指上滑 {var targetY = itemPosList[i + 1].LocalEulerAngles.z - 180;//Debug.Log($"ccc y {y} targetY {targetY} startIndex {startIndex} Z {transform.localEulerAngles.z}");if (eulerAnglersZ + StartAngle >= targetY){startIndex = i + 1;endIndex = startIndex + showItemCount - 1;break;}}else if (scrollRect.velocity.y < 0)//手指下滑{if (startIndex > 0 && startIndex < itemPosDic.Count){var targetY = itemPosDic[startIndex].LocalEulerAngles.z - 180;if (eulerAnglersZ + StartAngle <= targetY){startIndex = i - 1;endIndex = startIndex + showItemCount - 1;break;}}}}}//Debug.Log($"bbb startIndex {startIndex} endIndex {endIndex}");if (startIndex > 100 - showItemCount) {startIndex = 100 - showItemCount;}if (endIndex >= itemPosDic.Count) { return; }int index = 0;for (int i = startIndex; i < endIndex + 1; i++){if (index < scrollTestItems.Count && i < itemPosDic.Count){var item = scrollTestItems[index];item.Init(i, list[i]);var rect = item.gameObject.GetComponent<RectTransform>();rect.anchoredPosition3D = itemPosDic[i].AnchoredPosition;rect.localEulerAngles = itemPosDic[i].LocalEulerAngles;index += 1;}}});}public class CricleScrollItemPosData{public Vector3 AnchoredPosition;public Vector3 LocalEulerAngles;}}

2.UI目录

3.item克隆体，挂载脚本

4.按照图示，把CricleGrid脚本，挂在Items节点下，调整各个参数，运行即可。