public virtual void Drop(DropInfo dropInfo)
{
int insertIndex = dropInfo.InsertIndex;
IList destinationList = GetList(dropInfo.TargetCollection);
IEnumerable data = ExtractData(dropInfo.Data);
if (dropInfo.DragInfo.VisualSource == dropInfo.VisualTarget)
{
IList sourceList = GetList(dropInfo.DragInfo.SourceCollection);
foreach (object o in data)
{
int index = sourceList.IndexOf(o);
if (index != -1)
{
sourceList.RemoveAt(index);
if (sourceList == destinationList && index < insertIndex)
{
--insertIndex;
}
}
}
}
foreach (object o in data)
{
destinationList.Insert(insertIndex++, o);
}
}
public virtual void DragOver(DropInfo dropInfo)
{
if (CanAcceptData(dropInfo))
{
dropInfo.Effects = DragDropEffects.Copy;
}
}
protected static bool CanAcceptData(DropInfo dropInfo)
{
if (dropInfo.DragInfo.SourceCollection == dropInfo.TargetCollection)
{
return GetList(dropInfo.TargetCollection) != null;
}
else if (dropInfo.DragInfo.SourceCollection is ItemCollection)
{
return false;
}
else
{
if (TestCompatibleTypes(dropInfo.TargetCollection, dropInfo.Data))
{
return !IsChildOf(dropInfo.VisualTargetItem, dropInfo.DragInfo.VisualSourceItem);
}
else
{
return false;
}
}
}
static void DropTarget_PreviewDrop(object sender, DragEventArgs e)
{
DropInfo dropInfo = new DropInfo(sender, e, m_DragInfo, m_Format.Name);
IDropTarget dropHandler = GetDropHandler((UIElement)sender);
if (dropHandler != null)
{
dropHandler.Drop(dropInfo);
}
else
{
DefaultDropHandler.Drop(dropInfo);
}
e.Handled = true;
}
static void DropTarget_PreviewDragOver(object sender, DragEventArgs e)
{
DropInfo dropInfo = new DropInfo(sender, e, m_DragInfo, m_Format.Name);
IDropTarget dropHandler = GetDropHandler((UIElement)sender);
if (dropHandler != null)
{
dropHandler.DragOver(dropInfo);
}
else
{
DefaultDropHandler.DragOver(dropInfo);
}
e.Effects = dropInfo.Effects;
e.Handled = true;
Scroll((DependencyObject)sender, e);
}
void IDropTarget.Drop(DropInfo dropInfo)
{
Picture picture = (Picture)dropInfo.Data;
ListOfDraggedPictures.Add(picture);
GameScore += 10;
PicturesToDrag.Remove(picture);
}
void IDropTarget.DragOver(DropInfo dropInfo)
{
if (dropInfo.Data is Picture)
{
dropInfo.Effects = DragDropEffects.Move;
}
}
