fix

Runtime/RecyclerView/RecyclerView.cs

@@ -378,6 +378,87 @@ namespace AlicizaX.UI
             UpdateCurrentIndex(index);
         }
 
+        public void ScrollToWithAlignment(int index, ScrollAlignment alignment, float offset = 0f, bool smooth = false, float duration = 0.3f)
+        {
+            if (!scroll || scroller == null) return;
+
+            float targetPosition = CalculateScrollPositionWithAlignment(index, alignment, offset);
+
+            if (UGListExtensions.DebugScrollTo)
+            {
+                Debug.Log($"[RecyclerView] ScrollToWithAlignment: index={index}, alignment={alignment}, offset={offset}, targetPosition={targetPosition}, maxPosition={scroller.MaxPosition}");
+            }
+
+            if (duration > 0 && smooth)
+            {
+                scroller.ScrollTo(targetPosition, true);
+            }
+            else
+            {
+                scroller.ScrollTo(targetPosition, smooth);
+            }
+
+            if (!smooth)
+            {
+                Refresh();
+            }
+
+            UpdateCurrentIndex(index);
+        }
+
+        private float CalculateScrollPositionWithAlignment(int index, ScrollAlignment alignment, float offset)
+        {
+            if (RecyclerViewAdapter == null || index < 0 || index >= RecyclerViewAdapter.GetItemCount())
+            {
+                return scroller.Position;
+            }
+
+            float itemSize = GetItemSize(index);
+            float viewportLength = direction == Direction.Vertical ? layoutManager.ViewportSize.y : layoutManager.ViewportSize.x;
+            float contentLength = direction == Direction.Vertical ? layoutManager.ContentSize.y : layoutManager.ContentSize.x;
+
+            // Calculate the raw position of the item (without any clamping)
+            float itemPosition = CalculateRawItemPosition(index);
+
+            float targetPosition = alignment switch
+            {
+                ScrollAlignment.Start => itemPosition,
+                ScrollAlignment.Center => itemPosition - (viewportLength - itemSize) / 2f,
+                ScrollAlignment.End => itemPosition - viewportLength + itemSize,
+                _ => itemPosition
+            };
+
+            // Apply custom offset
+            targetPosition += offset;
+
+            if (UGListExtensions.DebugScrollTo)
+            {
+                Debug.Log($"[RecyclerView] CalculateScrollPosition: index={index}, itemPosition={itemPosition}, itemSize={itemSize}, viewportLength={viewportLength}, contentLength={contentLength}, targetPosition={targetPosition}, maxPosition={scroller.MaxPosition}");
+            }
+
+            // Clamp to valid scroll range
+            return Mathf.Clamp(targetPosition, 0, scroller.MaxPosition);
+        }
+
+        private float CalculateRawItemPosition(int index)
+        {
+            // Get spacing based on direction
+            Vector2 spacing = layoutManager.Spacing;
+            Vector2 padding = layoutManager.Padding;
+            float itemSize = GetItemSize(index);
+            float spacingValue = direction == Direction.Vertical ? spacing.y : spacing.x;
+            float paddingValue = direction == Direction.Vertical ? padding.y : padding.x;
+
+            // Calculate raw position without clamping
+            return index * (itemSize + spacingValue) + paddingValue;
+        }
+
+        private float GetItemSize(int index)
+        {
+            Vector2 itemSize = ViewProvider.CalculateViewSize(index);
+            return direction == Direction.Vertical ? itemSize.y : itemSize.x;
+        }
+
         #endregion
 
         #region Private Methods - Scroll Callbacks

Runtime/RecyclerView/ScrollAlignment.cs

@@ -0,0 +1,23 @@
+namespace AlicizaX.UI
+{
+    /// <summary>
+    /// Defines how an item should be aligned when scrolling to it
+    /// </summary>
+    public enum ScrollAlignment
+    {
+        /// <summary>
+        /// Align item to the top/left of the viewport
+        /// </summary>
+        Start,
+
+        /// <summary>
+        /// Align item to the center of the viewport
+        /// </summary>
+        Center,
+
+        /// <summary>
+        /// Align item to the bottom/right of the viewport
+        /// </summary>
+        End
+    }
+}

Runtime/RecyclerView/ScrollAlignment.cs.meta

@@ -0,0 +1,11 @@
+fileFormatVersion: 2
+guid: d17e4def4547e70499c0f63802da2772
+MonoImporter:
+  externalObjects: {}
+  serializedVersion: 2
+  defaultReferences: []
+  executionOrder: 0
+  icon: {instanceID: 0}
+  userData: 
+  assetBundleName: 
+  assetBundleVariant: 

Runtime/RecyclerView/UGListExtensions.cs

@@ -0,0 +1,94 @@
+using System;
+using UnityEngine;
+
+namespace AlicizaX.UI
+{
+    /// <summary>
+    /// Extension methods for UGList to provide enhanced scrolling functionality
+    /// </summary>
+    public static class UGListExtensions
+    {
+        /// <summary>
+        /// Enable debug logging for ScrollTo operations
+        /// </summary>
+        public static bool DebugScrollTo { get; set; } = false;
+
+        /// <summary>
+        /// Scrolls to a specific item with alignment and animation options
+        /// </summary>
+        /// <param name="ugList">The UGList instance</param>
+        /// <param name="index">The index of the item to scroll to</param>
+        /// <param name="alignment">How to align the item in the viewport (Start, Center, or End)</param>
+        /// <param name="offset">Additional offset in pixels to apply after alignment</param>
+        /// <param name="smooth">Whether to animate the scroll</param>
+        /// <param name="duration">Animation duration in seconds (only used when smooth is true)</param>
+        public static void ScrollTo<TData, TAdapter>(
+            this UGListBase<TData, TAdapter> ugList,
+            int index,
+            ScrollAlignment alignment = ScrollAlignment.Start,
+            float offset = 0f,
+            bool smooth = false,
+            float duration = 0.3f)
+            where TAdapter : Adapter<TData>
+            where TData : ISimpleViewData
+        {
+            if (ugList?.RecyclerView == null)
+            {
+                Debug.LogWarning("UGList or RecyclerView is null");
+                return;
+            }
+
+            if (DebugScrollTo)
+            {
+                Debug.Log($"[UGListExtensions] ScrollTo: index={index}, alignment={alignment}, offset={offset}, smooth={smooth}, duration={duration}");
+            }
+
+            ugList.RecyclerView.ScrollToWithAlignment(index, alignment, offset, smooth, duration);
+        }
+
+        /// <summary>
+        /// Scrolls to a specific item and aligns it at the start (top/left) of the viewport
+        /// </summary>
+        public static void ScrollToStart<TData, TAdapter>(
+            this UGListBase<TData, TAdapter> ugList,
+            int index,
+            float offset = 0f,
+            bool smooth = false,
+            float duration = 0.3f)
+            where TAdapter : Adapter<TData>
+            where TData : ISimpleViewData
+        {
+            ugList.ScrollTo(index, ScrollAlignment.Start, offset, smooth, duration);
+        }
+
+        /// <summary>
+        /// Scrolls to a specific item and aligns it at the center of the viewport
+        /// </summary>
+        public static void ScrollToCenter<TData, TAdapter>(
+            this UGListBase<TData, TAdapter> ugList,
+            int index,
+            float offset = 0f,
+            bool smooth = false,
+            float duration = 0.3f)
+            where TAdapter : Adapter<TData>
+            where TData : ISimpleViewData
+        {
+            ugList.ScrollTo(index, ScrollAlignment.Center, offset, smooth, duration);
+        }
+
+        /// <summary>
+        /// Scrolls to a specific item and aligns it at the end (bottom/right) of the viewport
+        /// </summary>
+        public static void ScrollToEnd<TData, TAdapter>(
+            this UGListBase<TData, TAdapter> ugList,
+            int index,
+            float offset = 0f,
+            bool smooth = false,
+            float duration = 0.3f)
+            where TAdapter : Adapter<TData>
+            where TData : ISimpleViewData
+        {
+            ugList.ScrollTo(index, ScrollAlignment.End, offset, smooth, duration);
+        }
+    }
+}

Runtime/RecyclerView/UGListExtensions.cs.meta

@@ -0,0 +1,3 @@
+fileFormatVersion: 2
+guid: a8f3c4e7d9b24f1a8c5e2d6f3a7b9c1e
+timeCreated: 1735197600

Runtime/RecyclerView/readme.md

@@ -0,0 +1,31 @@
+Simple Test
+
+public class TestData : ISimpleViewData
+{
+public string Name;
+}
+
+public class TestRecyclerView : MonoBehaviour
+{
+public RecyclerView itemListView;
+public UGList<TestData> list;
+
+    void Start()
+    {
+        list = UGListCreateHelper.Create<TestData>(itemListView, OnBtnItemClick);
+
+        List<TestData> datas = new();
+        for (int i = 0; i < 150; i++)
+        {
+            datas.Add(new TestData { Name = $"Item {i}" });
+        }
+
+        list.Data = datas;
+    }
+
+    private void OnBtnItemClick(TestData obj)
+    {
+        Debug.Log(obj.Name);
+    }
+
+}

Runtime/RecyclerView/readme.md.meta

@@ -0,0 +1,3 @@
+fileFormatVersion: 2
+guid: c0bd5104eb4344798791ff94b29eb63b
+timeCreated: 1766730473