private void ComputeLogicalNeighbors()
{
// Determine if any collection in our physical neighbor list is collapsed
bool isAnyNeighborCollapsed = false;
foreach (LayoutContext neighbor in PhysicalNeighbors)
{
if (neighbor.DockableCollection.IsCollapsed)
{
isAnyNeighborCollapsed = true;
break;
}
}
if (isAnyNeighborCollapsed)
{
// At least one neighbor is collapsed. There are two cases
// 1. A orthogonal peer of the neighbor will expand to cover the neighbor, in which case we can ignore the neighbor
// 2. One or more anticedents will expand, in which case they become logical neighbors.
_logicalNeighbors = new LinkedList <LayoutContext>();
foreach (LayoutContext neighbor in PhysicalNeighbors)
{
if (neighbor.DockableCollection.IsCollapsed)
{
if (neighbor.Edges[EdgesDockPosition].LogicalReplacements != null)
{
#if DEBUG
// The adjacent and opposing replacement sets should be identical
Debug.Assert(neighbor.Edges[LayoutContext.OpposingNeighbors[EdgesDockPosition]].LogicalReplacements != null);
LinkedListNode <LayoutContext> adjacentLink = neighbor.Edges[EdgesDockPosition].LogicalReplacements.First;
LinkedListNode <LayoutContext> opposingLink = neighbor.Edges[LayoutContext.OpposingNeighbors[EdgesDockPosition]].LogicalReplacements.First;
while (adjacentLink != null || opposingLink != null)
{
Debug.Assert(adjacentLink != null && opposingLink != null);
Debug.Assert(adjacentLink.Value == opposingLink.Value);
adjacentLink = adjacentLink.Next;
opposingLink = opposingLink.Next;
}
#endif
// If we have a replacement that is reachable, that replacement is the neighbor
bool foundLogicalNeighbors = false;
foreach (LayoutContext replacement in neighbor.Edges[EdgesDockPosition].LogicalReplacements)
{
if (LayoutContext.IsPhysicallyReachable(replacement, EdgesDockPosition))
{
foundLogicalNeighbors = true;
if (!_logicalNeighbors.Contains(replacement))
{
if (replacement.DockableCollection.IsCollapsed)
{
throw new InvalidProgramException();
}
_logicalNeighbors.AddLast(replacement);
}
}
}
// If we found no replacement, then the neighbors are the logical neighbors of the collapsed member
if (!foundLogicalNeighbors)
{
foreach (var logicalNeighbor in neighbor.Edges[EdgesDockPosition].LogicalNeighbors)
{
if (!_logicalNeighbors.Contains(logicalNeighbor))
{
if (logicalNeighbor.DockableCollection.IsCollapsed)
{
throw new InvalidProgramException();
}
_logicalNeighbors.AddLast(logicalNeighbor);
}
}
}
}
}
else if (!_logicalNeighbors.Contains(neighbor))
{
_logicalNeighbors.AddLast(neighbor);
}
}
}
else
{
_logicalNeighbors = PhysicalNeighbors;
}
}
