public IReadOnlyCollection <AbsoluteId> GetSelectedRootIds()
{
lock (LockObject)
{
return(SelectedRootIds.ToList());
}
}
private void AddToSelection([NotNull] EntityHierarchyElementViewModel element)
{
lock (LockObject)
{
if (!element.IsSelectable)
{
return;
}
// Add the entity id to the selected ids
SelectedIds.Add(element.Id);
// Check if one of its parents is in the selection
var parent = element.TransformParent;
while (parent != null)
{
if (SelectedIds.Contains(parent.Id))
{
break;
}
parent = parent.TransformParent;
}
// If so, the SelectedRootIds collection does not need to be updated.
if (parent != null)
{
return;
}
// Otherwise, it's a new root entity in the selection.
SelectedRootIds.Add(element.Id);
// Remove its children that were previously root entities in the selection.
foreach (var child in element.TransformChildren.SelectDeep(x => x.TransformChildren))
{
SelectedRootIds.Remove(child.Id);
}
}
}
private void RemoveFromSelection([NotNull] EntityHierarchyElementViewModel element)
{
lock (LockObject)
{
SelectedIds.Remove(element.Id);
// Remove the root entity from the selected root entities
if (SelectedRootIds.Remove(element.Id) && element.IsLoaded)
{
// Ensure all children that are selected are properly added to the selected root collection
foreach (var child in element.TransformChildren.SelectDeep(x => x.TransformChildren).Where(x => SelectedIds.Contains(x.Id)))
{
// Check if one of its parents is in the selection
var parent = child.TransformParent;
while (parent != element && parent != null)
{
if (SelectedIds.Contains(parent.Id))
{
break;
}
parent = parent.TransformParent;
}
// If so, the SelectedRootIds collection does not need to be updated.
if (parent != element)
{
return;
}
// Otherwise, it's a new root entity in the selection.
SelectedRootIds.Add(child.Id);
}
}
}
}
private void SelectedContentChanged(object sender, NotifyCollectionChangedEventArgs e)
{
if (!Editor.SceneInitialized)
{
return;
}
lock (LockObject)
{
// Retrieve old selection to pass it to the event
var oldSelectionIds = GetSelectedRootIds();
switch (e.Action)
{
case NotifyCollectionChangedAction.Add:
foreach (EntityHierarchyItemViewModel newItem in e.NewItems)
{
var root = newItem as SceneRootViewModel;
if (root != null)
{
AddToSelection(root);
}
else
{
foreach (var entity in newItem.InnerSubEntities)
{
AddToSelection(entity);
}
}
}
break;
case NotifyCollectionChangedAction.Remove:
foreach (EntityHierarchyItemViewModel oldItem in e.OldItems)
{
var root = oldItem as SceneRootViewModel;
if (root != null)
{
RemoveFromSelection(root);
}
else
{
foreach (var entity in oldItem.InnerSubEntities)
{
RemoveFromSelection(entity);
}
}
}
break;
case NotifyCollectionChangedAction.Reset:
SelectedIds.Clear();
SelectedRootIds.Clear();
break;
case NotifyCollectionChangedAction.Replace:
case NotifyCollectionChangedAction.Move:
throw new NotSupportedException("This operation is not supported.");
default:
throw new ArgumentOutOfRangeException();
}
RaiseSelectionUpdated(oldSelectionIds);
}
}
