private DataObject GetDataObject(FrameworkElement fe)
{
var data = FindDraggedItem(fe);
var ret = new DataObject(DragTypeName(), data);
TreeArrange.GetSupplementalFormats(fe)?.AddFormats(ret, data);
return(ret);
}
private void DragOver(object sender, DragEventArgs e)
{
if (TreeArrange.AdornmentTarget(sender) is {} droppedOnElement)
{
if (ExtractDraggedData(e) is not {
} droppedData)
{
DelegateDragOverToSupplementalDrag(sender, e);
return;
}
;
double relativePosition = RelativePosition(e, droppedOnElement);
droppedOnElement.Adorn(ComputeAdornerType(relativePosition, HasChildList(droppedOnElement, droppedData)));
e.Effects = DragDropEffects.Copy;
e.Handled = true;
}
}
private void Drop(object sender, DragEventArgs e)
{
if (TreeArrange.AdornmentTarget(sender) is not {
} droppedOnElement)
{
return;
}
if (ExtractDraggedData(e) is not {
} draggedItem)
{
TrySendSupplementalDropMessage(sender, e);
return;
}
if (TreeArrange.FindDraggedItem(droppedOnElement) is not {
} target || target == draggedItem)
{
return;
}
if (DroppingItemOnOwnChild(droppedOnElement, draggedItem))
{
return;
}
if (ListFinder.FindParentListContainingData(droppedOnElement, target) is not {
} items)
{
return;
}
e.Handled = true;
e.Effects = ComputeAdornerType(RelativePosition(e, droppedOnElement), HasChildList(droppedOnElement, draggedItem)) switch
{
DropAdornerKind.Top => InsertDroppedItemIntoTarget(items, target, draggedItem, 0),
DropAdornerKind.Bottom => InsertDroppedItemIntoTarget(items, target, draggedItem, 1),
_ => InsertDroppedItemIntoTarget(
ListFinder.FindChildListToHoldData(droppedOnElement, draggedItem) ?? items, null, draggedItem, 0)
};
}
private IDropTarget?SupplementalDropTarget() => TreeArrange.GetSupplementalDropTarget(rootElt);
