public static bool TryAddItem(DragDropItem item, DragDropTarget target)
{
if (item.attachedTarget != null)
{
return(false);
}
if (!IsChannelMatch(target, item))
{
return(false);
}
if (target.currentItemCount >= target.maxItemCount)
{
return(false);
}
DragDropEventData eventData = new DragDropEventData();
eventData.Reset();
eventData.external = true;
eventData.target = target;
eventData.item = item;
target.OnItemEnter(eventData);
item.OnItemEnter(eventData);
target.OnItemAttach(eventData);
item.OnItemAttach(eventData);
return(true);
}
public static bool TryAddItem(DragDropItem item, DragDropTarget target, bool sendCallback = true)
{
if (item == null || target == null)
{
return(false);
}
if (!(item.isActiveAndEnabled && target.isActiveAndEnabled))
{
return(false);
}
if (item.attachedTarget != null)
{
return(false);
}
if (!IsChannelMatch(target, item))
{
return(false);
}
DragDropEventData eventData = new DragDropEventData(!sendCallback);
eventData.Reset();
eventData.target = target;
eventData.item = item;
target.OnItemAttach(eventData);
item.OnItemAttach(eventData);
return(true);
}
public static bool IsChannelMatch(DragDropTarget target, DragDropItem item)
{
if (target.universalMatching || item.universalMatching)
{
return(true);
}
return((target.matchingChannel & item.matchingChannel) != 0);
}
internal bool AddInitialAttachedItem(DragDropItem item)
{
bool contain = attachedItems.Contains(item);
if (attachedItems.Count >= maxItemCount && !contain)
{
return(false);
}
if (!contain)
{
attachedItems.Add(item);
}
return(true);
}
private void OnEnable()
{
dragDropItem = target as DragDropItem;
m_OnItemExit = serializedObject.FindProperty("m_OnItemExit");
m_OnItemEnter = serializedObject.FindProperty("m_OnItemEnter");
m_OnItemDetach = serializedObject.FindProperty("m_OnItemDetach");
m_OnItemAttach = serializedObject.FindProperty("m_OnItemAttach");
m_OnItemDrag = serializedObject.FindProperty("m_OnItemDrag");
matchingChannel = serializedObject.FindProperty("matchingChannel");
matchingTag = serializedObject.FindProperty("matchingTag");
m_OnItemSetFree = serializedObject.FindProperty("m_OnItemSetFree");
m_OnItemClick = serializedObject.FindProperty("m_OnItemClick");
m_parentWhenDragging = serializedObject.FindProperty("m_parentWhenDragging");
m_longPressDetach = serializedObject.FindProperty("m_longPressDetach");
displayEvents = !Application.isPlaying;
}
public static int RemoveAllItems(DragDropTarget target, bool sendCallback = true)
{
var items = target.GetAllAttachedItems();
DragDropEventData eventData = new DragDropEventData(!sendCallback);
eventData.Reset();
eventData.target = target;
for (int count = items.Count, i = count - 1; i >= 0; --i)
{
DragDropItem item = items[i];
eventData.item = item;
target.OnItemDetach(eventData);
item.OnItemDetach(eventData);
item.OnSetFree(eventData);
}
return(items.Count);
}
internal bool CheckCanAttachItem(DragDropEventData eventData, out DragDropItem replacedItem)
{
replacedItem = null;
if (attachedItems.Count >= maxItemCount)
{
if (replaceItem)
{
replacedItem = attachedItems[0];
return(true);
}
else
{
return(false);
}
}
return(true);
}
public static bool TryRemoveItem(DragDropItem item, DragDropTarget target)
{
if (item.attachedTarget == target && target.HasItemAttached(item))
{
DragDropEventData eventData = new DragDropEventData();
eventData.Reset();
eventData.external = true;
eventData.target = target;
eventData.item = item;
target.OnItemDetach(eventData);
item.OnItemDetach(eventData);
target.OnItemExit(eventData);
item.OnItemExit(eventData);
item.OnSetFree(eventData);
return(true);
}
else
{
return(false);
}
}
public DragDropTarget FindDropTarget(PointerEventData pointerEventData, DragDropItem dragDropItem)
{
foreach (var ddt in managedTargets)
{
if (!ddt.isActiveAndEnabled)
{
continue;
}
if (!DragDropHelper.IsChannelMatch(ddt, dragDropItem))
{
continue;
}
bool contain = RectTransformUtility.RectangleContainsScreenPoint(ddt.rectTransform,
pointerEventData.position,
pointerEventData.pressEventCamera);
if (contain)
{
return(ddt);
}
}
return(null);
}
public static bool TryRemoveItem(DragDropItem item, DragDropTarget target, bool sendCallback = true)
{
if (item == null || target == null)
{
return(false);
}
if (item.attachedTarget == target && target.HasItemAttached(item))
{
DragDropEventData eventData = new DragDropEventData(!sendCallback);
eventData.Reset();
eventData.target = target;
eventData.item = item;
target.OnItemDetach(eventData);
item.OnItemDetach(eventData);
item.OnSetFree(eventData);
return(true);
}
else
{
return(false);
}
}
public bool HasItemAttached(DragDropItem item)
{
return(attachedItems.Contains(item));
}
public static bool IsChannelMatch(DragDropTarget target, DragDropItem item)
{
return((target.matchingChannel & item.matchingChannel) != 0);
}
public void UnRegister(DragDropItem item)
{
managedItems.Remove(item);
}
public void Register(DragDropItem item)
{
managedItems.Add(item);
}
public void OnPointerUp(PointerEventData eventData)
{
if (DragDropEventData.current.eligibleForClick)
{
OnClick(DragDropEventData.current);
}
if (!HandlingDragDropEvent())
{
DragDropEventData.current.Reset();
return;
}
if (DragDropEventData.current.valid)
{
DragDropItem replacedItem = null;
if (DragDropEventData.current.target.CheckCanAttachItem(DragDropEventData.current, out replacedItem))
{
if (replacedItem)
{
// 旧item 离开
DragDropEventData.current.isReplaced = true;
DragDropEventData.current.item = replacedItem;
DragDropEventData.current.target.OnItemDetach(DragDropEventData.current);
replacedItem.OnItemDetach(DragDropEventData.current);
// 新item 附着
DragDropEventData.current.isReplaced = false;
DragDropEventData.current.item = this;
DragDropEventData.current.target.OnItemAttach(DragDropEventData.current);
OnItemAttach(DragDropEventData.current);
// 旧item 附着到新item原来的target 完成交换
DragDropEventData.current.isReplaced = true;
DragDropEventData.current.item = replacedItem;
DragDropEventData.current.target = lastTarget;
if (DragDropEventData.current.valid)
{
lastTarget.OnItemAttach(DragDropEventData.current);
replacedItem.OnItemAttach(DragDropEventData.current);
}
else
{
replacedItem.attachedTarget = null;
replacedItem.OnSetFree(DragDropEventData.current);
}
}
else
{
DragDropEventData.current.target.OnItemAttach(DragDropEventData.current);
OnItemAttach(DragDropEventData.current);
}
}
else
{
DragDropEventData.current.target.OnItemExit(DragDropEventData.current);
OnItemExit(DragDropEventData.current);
}
}
else
{
OnSetFree(DragDropEventData.current);
}
DragDropEventData.current.Reset();
}
public static bool InitializePair(DragDropItem item, DragDropTarget target)
{
item.SetInitialTarget(target);
return(true);
}
