void CheckAndShowItem(int criticalItemType)
{
ScrollItem item = null;
int criticalIndex = -1;
while (true)
{
item = GetCriticalItem(criticalItemType);
criticalIndex = criticalItemIndex[criticalItemType];
//if (item == null && ShouldItemFullySeenAtIndex(criticalItemIndex[criticalItemType - 2]))
if (item == null && ShouldItemSeenAtIndex(criticalIndex))
{
ScrollItem newItem = itemPool.Get();
OnGetItemForDataIndex(newItem, criticalIndex);
//Debug.Log("创建了 " + criticalIndex);
managedItems[criticalIndex].item = newItem;
criticalItemIndex[criticalItemType - 2] = criticalIndex;
if (criticalItemType == CriticalItemType.UpToShow)
{
// 最上显示了一个
criticalItemIndex[criticalItemType]--;
}
else
{
// 最下显示了一个
criticalItemIndex[criticalItemType]++;
}
criticalItemIndex[criticalItemType] = Mathf.Clamp(criticalItemIndex[criticalItemType], 0, m_dataCount - 1);
}
else
{
break;
}
}
}
private RectTransform GetNewItem(int index)
{
RectTransform item;
if (itemGetFunc != null)
{
item = itemGetFunc(index);
}
else
{
item = itemPool.Get();
}
return(item);
}
public void UpdateData()
{
int newDataCount = 0;
if (itemCoundFunc != null)
{
newDataCount = itemCoundFunc();
}
if (newDataCount != managedItems.Length)
{
if (newDataCount > managedItems.Length) //增加
{
Array.Resize(ref managedItems, newDataCount);
}
else //减少
{
for (int i = newDataCount; i < m_dataCount; i++)
{
if (managedItems[i].item != null)
{
itemPool.Recycle(managedItems[i].item);
managedItems[i].item = null;
}
}
//Array.Resize(ref managedItems, newDataCount); //减少时保留之前多余的空位
}
m_dataCount = newDataCount;
}
CacheRect();
int showCount = Mathf.Min(maxShownCount, m_dataCount);
int restCount = showCount;
bool hasItem, shouldShow;
int firstIndex = -1, lastIndex = -1;
for (int i = 0; i < m_dataCount && restCount > 0; i++)
{
hasItem = managedItems[i].item != null;
shouldShow = ShouldItemSeenAtIndex(i);
if (shouldShow)
{
restCount--;
if (firstIndex == -1)
{
firstIndex = i;
}
lastIndex = i;
}
if (hasItem && shouldShow)
{
// 应显示且已显示
SetDataForItemAtIndex(managedItems[i].item, i);
continue;
}
if (hasItem == shouldShow)
{
// 不应显示且未显示
continue;
}
if (hasItem && !shouldShow)
{
// 不该显示 但是有
itemPool.Recycle(managedItems[i].item);
managedItems[criticalItemIndex[i]].item = null;
continue;
}
if (shouldShow && !hasItem)
{
// 需要显示 但是没有
RectTransform item = itemPool.Get();
OnGetItemForDataIndex(item, i);
managedItems[i].item = item;
continue;
}
}
// content.localPosition = Vector2.zero;
criticalItemIndex[CriticalItemType.UpToHide] = firstIndex;
criticalItemIndex[CriticalItemType.DownToHide] = lastIndex;
criticalItemIndex[CriticalItemType.UpToShow] = Mathf.Max(firstIndex - 1, 0);
criticalItemIndex[CriticalItemType.DownToShow] = Mathf.Min(lastIndex + 1, m_dataCount - 1);
}
private void InternalUpdateData()
{
willUpdateData = false;
int newDataCount = 0;
if (itemCoundFunc != null)
{
newDataCount = itemCoundFunc();
}
if (newDataCount != managedItems.Count)
{
if (managedItems.Count < newDataCount) //增加
{
foreach (var itemWithRect in managedItems)
{
// 重置所有rect
itemWithRect.rectDirty = true;
}
while (managedItems.Count < newDataCount)
{
managedItems.Add(new ScrollItemWithRect());
}
}
else //减少 保留空位 避免GC
{
for (int i = 0, count = managedItems.Count; i < count; ++i)
{
// 重置所有rect
managedItems[i].rectDirty = true;
// 超出部分 清理回收item
if (i >= newDataCount)
{
if (managedItems[i].item != null)
{
itemPool.Recycle(managedItems[i].item);
managedItems[i].item = null;
}
}
}
}
}
m_dataCount = newDataCount;
// CacheRect();
int showCount = Mathf.Min(maxShownCount, m_dataCount);
int restCount = showCount;
bool hasItem, shouldShow;
int firstIndex = -1, lastIndex = -1;
for (int i = 0; i < m_dataCount && restCount > 0; i++)
{
hasItem = managedItems[i].item != null;
shouldShow = ShouldItemSeenAtIndex(i);
if (shouldShow)
{
restCount--;
if (firstIndex == -1)
{
firstIndex = i;
}
lastIndex = i;
}
if (hasItem && shouldShow)
{
// 应显示且已显示
SetDataForItemAtIndex(managedItems[i].item, i);
continue;
}
if (hasItem == shouldShow)
{
// 不应显示且未显示
if (firstIndex != -1)
{
// 已经遍历完所有要显示的了 后边的先跳过
break;
}
continue;
}
if (hasItem && !shouldShow)
{
// 不该显示 但是有
itemPool.Recycle(managedItems[i].item);
managedItems[i].item = null;
continue;
}
if (shouldShow && !hasItem)
{
// 需要显示 但是没有
RectTransform item = itemPool.Get();
OnGetItemForDataIndex(item, i);
managedItems[i].item = item;
continue;
}
}
// content.localPosition = Vector2.zero;
criticalItemIndex[CriticalItemType.UpToHide] = firstIndex;
criticalItemIndex[CriticalItemType.DownToHide] = lastIndex;
criticalItemIndex[CriticalItemType.UpToShow] = Mathf.Max(firstIndex - 1, 0);
criticalItemIndex[CriticalItemType.DownToShow] = Mathf.Min(lastIndex + 1, m_dataCount - 1);
}
public static Dictionary <T, U> Get()
{
return(pool.Get());
}
public static List <T> Get()
{
return(pool.Get());
}