private PlacementOperation(DesignItem[] items, PlacementType type)
{
List <DesignItem> moveableItems;
this.currentContainerBehavior = GetPlacementBehavior(items, out moveableItems, type);
PlacementInformation[] information = new PlacementInformation[moveableItems.Count];
for (int i = 0; i < information.Length; i++)
{
information[i] = new PlacementInformation(moveableItems[i], this);
}
this.placedItems = new ReadOnlyCollection <PlacementInformation>(information);
this.type = type;
this.currentContainer = moveableItems[0].Parent;
this.changeGroup = moveableItems[0].Context.OpenGroup(type.ToString(), moveableItems);
}
/// <summary>
/// Starts a new placement operation that changes the placement of <paramref name="placedItems"/>.
/// </summary>
/// <param name="placedItems">The items to be placed.</param>
/// <param name="type">The type of the placement.</param>
/// <returns>A PlacementOperation object.</returns>
/// <remarks>
/// You MUST call either <see cref="Abort"/> or <see cref="Commit"/> on the returned PlacementOperation
/// once you are done with it, otherwise a ChangeGroup will be left open and Undo/Redo will fail to work!
/// </remarks>
public static PlacementOperation Start(ICollection <DesignItem> placedItems, PlacementType type)
{
if (placedItems == null)
{
throw new ArgumentNullException("placedItems");
}
if (type == null)
{
throw new ArgumentNullException("type");
}
DesignItem[] items = placedItems.ToArray();
if (items.Length == 0)
{
throw new ArgumentException("placedItems.Length must be > 0");
}
PlacementOperation op = new PlacementOperation(items, type);
try
{
if (op.currentContainerBehavior == null)
{
throw new PlacementOperationException("Starting the operation is not supported");
}
op.currentContainerBehavior.BeginPlacement(op);
foreach (PlacementInformation info in op.placedItems)
{
info.OriginalBounds = op.currentContainerBehavior.GetPosition(op, info.Item);
info.Bounds = info.OriginalBounds;
}
}
catch (Exception ex)
{
Debug.WriteLine(ex.ToString());
op.changeGroup.Abort();
throw;
}
return(op);
}
/// <summary>
/// Try to insert new components into the container.
/// </summary>
/// <param name="container">The container that should become the parent of the components.</param>
/// <param name="placedItems">The components to add to the container.</param>
/// <param name="positions">The rectangle specifying the position the element should get.</param>
/// <param name="type">The type </param>
/// <returns>The operation that inserts the new components, or null if inserting is not possible.</returns>
public static PlacementOperation TryStartInsertNewComponents(DesignItem container,
IList <DesignItem> placedItems, IList <Rect> positions, PlacementType type)
{
if (container == null)
{
throw new ArgumentNullException("container");
}
if (placedItems == null)
{
throw new ArgumentNullException("placedItems");
}
if (positions == null)
{
throw new ArgumentNullException("positions");
}
if (type == null)
{
throw new ArgumentNullException("type");
}
if (placedItems.Count == 0)
{
throw new ArgumentException("placedItems.Count must be > 0");
}
if (placedItems.Count != positions.Count)
{
throw new ArgumentException("positions.Count must be = placedItems.Count");
}
DesignItem[] items = placedItems.ToArray();
PlacementOperation op = new PlacementOperation(items, type);
try
{
for (int i = 0; i < items.Length; i++)
{
op.placedItems[i].OriginalBounds = op.placedItems[i].Bounds = positions[i];
}
op.currentContainer = container;
op.currentContainerBehavior = container.GetBehavior <IPlacementBehavior>();
if (op.currentContainerBehavior == null || !op.currentContainerBehavior.CanEnterContainer(op, true))
{
op.changeGroup.Abort();
return(null);
}
op.currentContainerBehavior.EnterContainer(op);
}
catch (Exception ex)
{
Debug.WriteLine(ex.ToString());
op.changeGroup.Abort();
throw;
}
return(op);
}
/// <summary>
/// Gets the placement behavior associated with the specified items.
/// </summary>
public static IPlacementBehavior GetPlacementBehavior(ICollection <DesignItem> items,
out List <DesignItem> moveableItems, PlacementType placementType)
{
moveableItems = new List <DesignItem>();
if (items == null)
{
throw new ArgumentNullException("items");
}
if (items.Count == 0)
{
return(null);
}
var possibleItems = items;
if (!items.Any(x => x.Parent == null))
{
var itemsPartentGroup = items.GroupBy(x => x.Parent);
var parents = itemsPartentGroup.Select(x => x.Key).OrderBy(x => x.DepthLevel).First();
possibleItems = itemsPartentGroup.Where(x => x.Key.DepthLevel == parents.DepthLevel)
.SelectMany(x => x)
.ToList();
}
var first = possibleItems.First();
DesignItem parent = first.Parent;
moveableItems.Add(first);
foreach (DesignItem item in possibleItems.Skip(1))
{
if (item.Parent != parent)
{
if (placementType != PlacementType.MoveAndIgnoreOtherContainers)
{
return(null);
}
}
else
{
moveableItems.Add(item);
}
}
if (parent != null)
{
return(parent.GetBehavior <IPlacementBehavior>());
}
else if (possibleItems.Count == 1)
{
return(first.GetBehavior <IRootPlacementBehavior>());
}
else
{
return(null);
}
}
