com.alicizax.unity.ui.exten.../Runtime/RecyclerView/Layout/LinearLayoutManager.cs
陈思海 dc8c840d69 RecyclerView 大优化
优化RecycleView 渲染架构
优化RecyclerView 渲染性能 增加 缓存 异步
增加Navagation导航锚点相关
2026-03-31 15:18:50 +08:00

148 lines
4.6 KiB
C#

using System;
using UnityEngine;
namespace AlicizaX.UI
{
[Serializable]
public class LinearLayoutManager : LayoutManager
{
protected float lineHeight;
public LinearLayoutManager() { }
public override Vector2 CalculateContentSize()
{
int itemCount = adapter != null ? adapter.GetItemCount() : 0;
if (itemCount <= 0)
{
lineHeight = 0f;
return direction == Direction.Vertical
? new Vector2(contentSize.x, padding.y * 2)
: new Vector2(padding.x * 2, contentSize.y);
}
Vector2 size = viewProvider.CalculateViewSize(0);
lineHeight = direction == Direction.Vertical ? size.y : size.x;
float position;
if (direction == Direction.Vertical)
{
position = itemCount * (lineHeight + spacing.y) - spacing.y;
return new Vector2(contentSize.x, position + padding.y * 2);
}
position = itemCount * (lineHeight + spacing.x) - spacing.x;
return new Vector2(position + padding.x * 2, contentSize.y);
}
public override Vector2 CalculatePosition(int index)
{
float position;
if (direction == Direction.Vertical)
{
position = index * (lineHeight + spacing.y) - ScrollPosition;
return new Vector2(0, position + padding.y);
}
position = index * (lineHeight + spacing.x) - ScrollPosition;
return new Vector2(position + padding.x, 0);
}
public override Vector2 CalculateContentOffset()
{
if (lineHeight <= 0f)
{
return Vector2.zero;
}
float len = GetFitContentSize();
if (direction == Direction.Vertical)
{
return new Vector2(0, (len - lineHeight) / 2);
}
return new Vector2((len - lineHeight) / 2, 0);
}
public override Vector2 CalculateViewportOffset()
{
if (lineHeight <= 0f)
{
return Vector2.zero;
}
if (direction == Direction.Vertical)
{
return new Vector2(0, (viewportSize.y - lineHeight) / 2);
}
return new Vector2((viewportSize.x - lineHeight) / 2, 0);
}
public override int GetStartIndex()
{
if (adapter == null || adapter.GetItemCount() <= 0)
{
return 0;
}
float len = direction == Direction.Vertical ? lineHeight + spacing.y : lineHeight + spacing.x;
if (len <= 0f)
{
return 0;
}
int index = Mathf.FloorToInt(ScrollPosition / len);
return Mathf.Max(0, index);
}
public override int GetEndIndex()
{
if (adapter == null || adapter.GetItemCount() <= 0)
{
return -1;
}
float viewLength = direction == Direction.Vertical ? viewportSize.y : viewportSize.x;
float len = direction == Direction.Vertical ? lineHeight + spacing.y : lineHeight + spacing.x;
if (len <= 0f)
{
return adapter.GetItemCount() - 1;
}
int index = Mathf.FloorToInt((ScrollPosition + viewLength) / len);
return Mathf.Min(index, adapter.GetItemCount() - 1);
}
public override float IndexToPosition(int index)
{
if (adapter == null || adapter.GetItemCount() <= 0 || index < 0 || index >= adapter.GetItemCount()) return 0;
float len, viewLength, position;
if (direction == Direction.Vertical)
{
len = index * (lineHeight + spacing.y);
viewLength = viewportSize.y;
position = len + viewLength > contentSize.y ? contentSize.y - viewportSize.y : len;
}
else
{
len = index * (lineHeight + spacing.x);
viewLength = viewportSize.x;
position = len + viewLength > contentSize.x ? contentSize.x - viewportSize.x : len;
}
return position;
}
public override int PositionToIndex(float position)
{
float len = direction == Direction.Vertical ? lineHeight + spacing.y : lineHeight + spacing.x;
if (len <= 0f)
{
return 0;
}
int index = Mathf.RoundToInt(position / len);
return index;
}
}
}