public virtual void Add(object data)
{
var model = new ScrollListItemModel(data, itemDefaultfSize);
_itemModels.Add(model);
MarkDirty(true);
}
public virtual void Insert(int index, object data)
{
var model = new ScrollListItemModel(data, itemDefaultfSize);
_itemModels.Insert(index, model);
if (index <= lastStartIndex)
{
MarkDirty(true, EKeepPaddingType.END);
}
else
{
MarkDirty(true);
}
}
/// <summary>
/// 创建一个列表项Item
/// </summary>
/// <param name="data"></param>
/// <param name="dataIdx"></param>
/// <param name="lastShowingItems"></param>
/// <returns></returns>
protected ScrollListItem CreateItem(ScrollListItemModel model, int dataIdx, Dictionary <ScrollListItemModel, ScrollListItem> lastShowingItems)
{
ScrollListItem item;
if (lastShowingItems.ContainsKey(model) && lastShowingItems[model].index == dataIdx) //本来就在显示列表中，直接返回
{
item = lastShowingItems[model];
lastShowingItems.Remove(model);
}
else
{
if (_recycledItems.Count > 0)
{
ScrollListItem tempItem = null;
//tempItem = _recycledItems[0];
int idx = _recycledItems.Count;
while (--idx > -1)
{
tempItem = _recycledItems[idx];
if (tempItem.index == dataIdx && tempItem.data.Equals(model.data)) //以前回收的一个对象，刚好对应的数据一致，直接返回
{
item = tempItem;
_recycledItems.RemoveAt(idx);
item.gameObject.SetActive(true);
RenderItem(item, model.data, false);
return(item);
}
}
//没有绝对匹配的，则抽取最后找到的item，之后刷新数据并返回
item = tempItem;
_recycledItems.Remove(tempItem);
//当一个列表项，将被复用时触发
onItemBeforeReuse?.Invoke(item);
}
else
{
var go = GameObject.Instantiate(itemPrefab, content);
if (false == go.activeInHierarchy)
{
go.SetActive(true);
}
item = go.AddComponent <ScrollListItem>();
item.rectTransform.anchorMin = Vector2.up;
item.rectTransform.anchorMax = Vector2.up;
item.rectTransform.pivot = Vector2.up;
//Debug.Log($"新生成的 Item GameObject");
}
var name = string.Format("item_{0}", dataIdx);
item.gameObject.name = name;
item.index = dataIdx;
item.data = model.data;
item.width = _itemModels[dataIdx].width;
item.height = _itemModels[dataIdx].height;
if (false == item.gameObject.activeInHierarchy)
{
item.gameObject.SetActive(true);
}
RenderItem(item, model.data, true);
}
if (item.index != dataIdx)
{
//插入列表项可能导致数据索引改变
item.index = dataIdx;
}
return(item);
}