public virtual void SetIsDragPossible(CanonicSelection canonicSelectedItemList)
{
if (canonicSelectedItemList != null)
{
this.DragParentItem = canonicSelectedItemList.DraggedItemParent;
this.ItemList = canonicSelectedItemList.ItemList;
this.AllowDropCopy = canonicSelectedItemList.AllItemsCloneable;
}
}
/// <summary>
/// Gets the list of selected ims.
/// </summary>
/// <param name="canonicSelectedItemList">The list to fill.</param>
/// <returns>True if successful; otherwise, false.</returns>
protected virtual bool GetCanonicSelectedItemList(CanonicSelection canonicSelectedItemList)
{
if (SelectedItems.Count == 0)
{
return(false);
}
List <object> SortedSelectedItems = new List <object>();
#if NETCOREAPP3_1
foreach (object?Item in SelectedItems)
{
if (Item != null)
{
SortedSelectedItems.Add(Item);
}
}
#else
foreach (object Item in SelectedItems)
{
SortedSelectedItems.Add(Item);
}
#endif
SortedSelectedItems.Sort(SortByIndex);
object FirstItem = SortedSelectedItems[0];
if (IsContent(FirstItem))
{
return(false);
}
object?FirstItemParent = GetItemParent(FirstItem);
if (FirstItemParent != null)
{
if (GetItemsWithSameParent(SortedSelectedItems, FirstItemParent, canonicSelectedItemList))
{
canonicSelectedItemList.SetDraggedItemParent(FirstItemParent);
return(true);
}
if (GetItemsInSameBranch(SortedSelectedItems, FirstItemParent, canonicSelectedItemList))
{
canonicSelectedItemList.SetDraggedItemParent(FirstItemParent);
return(true);
}
}
return(false);
}
/// <summary>
/// Updates the drag drop allowed properties.
/// </summary>
protected virtual void UpdateIsDragDropPossible()
{
CanonicSelection CanonicSelectedItemList = new CanonicSelection(CreateItemList());
if (GetCanonicSelectedItemList(CanonicSelectedItemList))
{
DragSource.SetIsDragPossible(CanonicSelectedItemList);
}
else
{
DragSource.ClearIsDragPossible();
DragSource.ClearFlatDraggedItemList();
}
}
/// <summary>
/// Changes the drag activity.
/// </summary>
/// <param name="canonicSelectedItemList">The lost of selected items.</param>
public virtual void SetIsDragPossible(CanonicSelection canonicSelectedItemList)
{
DraggedItemParent = canonicSelectedItemList.DraggedItemParent;
ItemList = canonicSelectedItemList.ItemList;
AllowDropCopy = canonicSelectedItemList.AllItemsCloneable;
}
/// <summary>
/// Gets the list of selected items with the same parent.
/// </summary>
/// <param name="sortedSelectedItems">The list of selected items, sorted.</param>
/// <param name="firstItemParent">The parent of the first item.</param>
/// <param name="canonicSelectedItemList">The list of selected items, unsorted.</param>
/// <returns>True if successful; otherwise, false.</returns>
protected virtual bool GetItemsWithSameParent(IList sortedSelectedItems, object firstItemParent, CanonicSelection canonicSelectedItemList)
{
if (sortedSelectedItems == null || canonicSelectedItemList == null)
{
return(false);
}
canonicSelectedItemList.AllItemsCloneable = true;
#if NETCOREAPP3_1
foreach (object?Item in sortedSelectedItems)
{
if (Item != null)
{
if (GetItemParent(Item) != firstItemParent)
{
return(false);
}
canonicSelectedItemList.ItemList.Add(Item);
if (!IsItemCloneable(Item))
{
canonicSelectedItemList.AllItemsCloneable = false;
}
}
}
#else
foreach (object Item in sortedSelectedItems)
{
if (GetItemParent(Item) != firstItemParent)
{
return(false);
}
canonicSelectedItemList.ItemList.Add(Item);
if (!IsItemCloneable(Item))
{
canonicSelectedItemList.AllItemsCloneable = false;
}
}
#endif
return(true);
}
/// <summary>
/// Checks if all items of a branch are selected.
/// </summary>
/// <param name="sortedSelectedItems">The list of selected items, sorted.</param>
/// <param name="item">The parent item.</param>
/// <param name="canonicSelectedItemList">The list of selected items, unsorted.</param>
/// <returns>True if in the same branch; otherwise, false.</returns>
protected virtual bool IsEntireBranchSelected(IList sortedSelectedItems, object item, CanonicSelection canonicSelectedItemList)
{
if (sortedSelectedItems == null || canonicSelectedItemList == null)
{
return(false);
}
if (!IsItemCloneable(item))
{
canonicSelectedItemList.AllItemsCloneable = false;
}
canonicSelectedItemList.RecordCount++;
if (IsExpanded(item))
{
IList Children = GetItemChildren(item);
#if NETCOREAPP3_1
foreach (object?ChildItem in Children)
{
if (ChildItem != null)
{
if (!sortedSelectedItems.Contains(ChildItem))
{
return(false);
}
if (!IsEntireBranchSelected(sortedSelectedItems, ChildItem, canonicSelectedItemList))
{
return(false);
}
}
}
#else
foreach (object ChildItem in Children)
{
if (!sortedSelectedItems.Contains(ChildItem))
{
return(false);
}
if (!IsEntireBranchSelected(sortedSelectedItems, ChildItem, canonicSelectedItemList))
{
return(false);
}
}
#endif
}
return(true);
}
/// <summary>
/// Gets the list of selected items in the same branch.
/// </summary>
/// <param name="sortedSelectedItems">The list of selected items, sorted.</param>
/// <param name="firstItemParent">The parent of the first item.</param>
/// <param name="canonicSelectedItemList">The list of selected items, unsorted.</param>
/// <returns>True if successful; otherwise, false.</returns>
protected virtual bool GetItemsInSameBranch(IList sortedSelectedItems, object firstItemParent, CanonicSelection canonicSelectedItemList)
{
if (sortedSelectedItems == null || canonicSelectedItemList == null)
{
return(false);
}
IList Children = GetItemChildren(firstItemParent);
#if NETCOREAPP3_1
foreach (object?ChildItem in Children)
{
if (ChildItem != null)
{
if (sortedSelectedItems.Contains(ChildItem))
{
if (!canonicSelectedItemList.ItemList.Contains(ChildItem))
{
canonicSelectedItemList.ItemList.Add(ChildItem);
}
if (!IsEntireBranchSelected(sortedSelectedItems, ChildItem, canonicSelectedItemList))
{
return(false);
}
}
}
}
#else
foreach (object ChildItem in Children)
{
if (sortedSelectedItems.Contains(ChildItem))
{
if (!canonicSelectedItemList.ItemList.Contains(ChildItem))
{
canonicSelectedItemList.ItemList.Add(ChildItem);
}
if (!IsEntireBranchSelected(sortedSelectedItems, ChildItem, canonicSelectedItemList))
{
return(false);
}
}
}
#endif
if (canonicSelectedItemList.RecordCount < sortedSelectedItems.Count)
{
return(false);
}
return(true);
}