/// <summary>
/// Resets positions of an list item according to its index
/// </summary>
/// <param name="item">item to be reset</param>
private void ResetItemPosition(ListItemBase item)
{
float position = item.Index * (itemSize + spacing) + itemSize / 2;
var rectTransform = item.gameObject.GetComponent <RectTransform>();
switch (scrollOrientation)
{
case ScrollOrientation.HORIZONTAL:
rectTransform.anchorMin = new Vector2(0, 0);
rectTransform.anchorMax = new Vector2(0, 1);
rectTransform.anchoredPosition = new Vector2(position, 0);
rectTransform.offsetMin = new Vector2(rectTransform.offsetMin.x, 0);
rectTransform.offsetMax = new Vector2(rectTransform.offsetMax.x, 0);
break;
case ScrollOrientation.VERTICAL:
rectTransform.anchorMin = new Vector2(0, 1);
rectTransform.anchorMax = new Vector2(1, 1);
rectTransform.anchoredPosition = new Vector2(0, -position);
rectTransform.offsetMin = new Vector2(0, rectTransform.offsetMin.y);
rectTransform.offsetMax = new Vector2(0, rectTransform.offsetMax.y);
break;
}
}
private void RecycleItem(ScrollDirection direction)
{
ListItemBase firstItem = itemsList[0];
ListItemBase lastItem = itemsList[itemsList.Count - 1];
float targetPosition = (itemSize + spacing);
switch (direction)
{
case ScrollDirection.NEXT:
switch (scrollOrientation)
{
case ScrollOrientation.HORIZONTAL:
firstItem.Position =
new Vector2(lastItem.Position.x + targetPosition, firstItem.Position.y);
break;
case ScrollOrientation.VERTICAL:
firstItem.Position =
new Vector2(firstItem.Position.x, lastItem.Position.y - targetPosition);
break;
}
firstItem.Index = lastItemIndex;
firstItem.transform.SetAsLastSibling();
itemsList.RemoveAt(0);
itemsList.Add(firstItem);
ItemLoaded(firstItem);
break;
case ScrollDirection.PREVIOUS:
switch (scrollOrientation)
{
case ScrollOrientation.HORIZONTAL:
lastItem.Position = new Vector2(firstItem.Position.x - targetPosition, lastItem.Position.y);
break;
case ScrollOrientation.VERTICAL:
lastItem.Position = new Vector2(lastItem.Position.x, firstItem.Position.y + targetPosition);
break;
}
lastItem.Index = lastItemIndex - itemsList.Count;
lastItem.transform.SetAsFirstSibling();
itemsList.RemoveAt(itemsList.Count - 1);
itemsList.Insert(0, lastItem);
ItemLoaded(lastItem);
break;
}
Canvas.ForceUpdateCanvases();
}
protected void HandleOnItemLoadedHandler(ListItemBase item)
{
if (item == selectedItem)
{
selectedItem.Select(selectedIndex == selectedItem.Index);
}
item.OnLoad(Data[item.Index]);
}
public void ItemSelected(ListItemBase item, bool clear = false)
{
if (OnItemSelected != null)
{
OnItemSelected(item);
if (clear)
{
OnItemSelected = null;
}
}
}
protected void HandleOnItemSelectedHandler(ListItemBase item)
{
if (selectedItem != null)
{
selectedItem.Select(false);
}
selectedItem = (FriendListItem)item;
selectedItem.Select(true);
selectedIndex = selectedItem.Index;
listener.OnContactSelected(selectedIndex);
}
private ListItemBase CreateNewItem(ListItemBase prefab, int index)
{
GameObject instance = Instantiate(prefab.gameObject, Vector3.zero, Quaternion.identity);
instance.transform.SetParent(content.transform);
instance.transform.localScale = Vector3.one;
instance.SetActive(true);
var item = instance.GetComponent <ListItemBase>();
item.Index = index;
ResetItemPosition(item);
return(item);
}
public void InsertItem(int index, ListItemBase listItemPrefab)
{
if (itemsTotal < 2 * itemsVisible)
{
ListItemBase item = CreateNewItem(listItemPrefab, index);
item.OnSelected = HandleOnSelectedHandler;
itemsList.Insert(index, item);
ReindexItems(index);
ItemLoaded(item);
}
itemsTotal++;
lastItemIndex = itemsList.Count - 1;
itemsToRecycleAfter++;
ResizeContentToFitItems();
}
public void AddItem(ListItemBase listItemPrefab)
{
if (itemsTotal < 2 * itemsVisible)
{
int i = itemsList.Count;
ListItemBase item = CreateNewItem(listItemPrefab, i);
item.OnSelected = HandleOnSelectedHandler;
itemsList.Add(item);
ItemLoaded(item);
}
itemsTotal++;
lastItemIndex = itemsList.Count - 1;
itemsToRecycleAfter++;
ResizeContentToFitItems();
}
void HandleOnSelectedHandler(ListItemBase item)
{
ItemSelected(item);
}
public void Create(int items, ListItemBase listItemPrefab)
{
switch (scrollOrientation)
{
case ScrollOrientation.HORIZONTAL:
scrollRect.vertical = false;
scrollRect.horizontal = true;
content.anchorMin = new Vector2(0, 0);
content.anchorMax = new Vector2(0, 1);
if (fitItemToViewport)
{
listItemPrefab.Size = new Vector2(viewport.rect.width, listItemPrefab.Size.y);
}
itemSize = listItemPrefab.Size.x;
content.sizeDelta = new Vector2(itemSize * items + spacing * (items - 1), 0);
break;
case ScrollOrientation.VERTICAL:
scrollRect.vertical = true;
scrollRect.horizontal = false;
content.anchorMin = new Vector2(0, 1);
content.anchorMax = new Vector2(1, 1);
if (fitItemToViewport)
{
listItemPrefab.Size = new Vector2(listItemPrefab.Size.x, viewport.rect.height);
}
itemSize = listItemPrefab.Size.y;
content.sizeDelta = new Vector2(0, itemSize * items + spacing * (items - 1));
break;
}
if (centerOnItem)
{
scrollRect.inertia = false;
}
itemsVisible = Mathf.CeilToInt(GetViewportSize() / itemSize);
int itemsToInstantiate = itemsVisible;
if (itemsVisible == 1)
{
itemsToInstantiate = 5;
}
else if (itemsToInstantiate < items)
{
itemsToInstantiate *= 2;
}
if (itemsToInstantiate > items)
{
itemsToInstantiate = items;
}
itemsList = new List <ListItemBase>();
for (int i = 0; i < itemsToInstantiate; i++)
{
ListItemBase item = CreateNewItem(listItemPrefab, i);
item.OnSelected = HandleOnSelectedHandler;
item.Index = i;
itemsList.Add(item);
ItemLoaded(item);
}
itemsTotal = items;
lastItemIndex = itemsList.Count - 1;
itemsToRecycleAfter = itemsList.Count - itemsVisible;
scrollRect.onValueChanged.AddListener(position =>
{
if (!centerOnItem)
{
Recycle();
}
});
}
