public BoxComposition(BoxCompositionViewModel viewModel)
{
this.DataContext = viewModel;
//this.Background = Brushes.Aqua;
Focusable = false;
locations = new List<Point>();
Width = double.NaN;
boxes = new FacadeMapCollection<UIElement, Box>(this.Children, uielement => (Box)uielement);
viewModel.Boxes.CollectionChanged += boxesCollectionChanged;
Contract.Assert(viewModel.Boxes.Count != 0);
//this.arrangement is initialized in InitializeComponents
}
/// <summary> Gets the only box in this composition construction that should receive initial focus. Returns null if no such box exists. </summary>
/// <param name="result"> The box composition that was created using this composition construction specifier. </param>
internal BoxViewModel GetCentralBox(BoxCompositionViewModel result, out int initialCaretPosition)
{
Contract.Requires(result != null);
Contract.Requires(result.Count == this.Contents.Count);
//this method works recursively: If the box that should receive initial focus is a direct child of the current box composition, the recursion terminates
//otherwise the recursion is continued on the box composition containing the box (however deeply nested) that should receive initial focus
int indexOfCentralChild = this.Contents.IndexOf(bcs => bcs.HasInitialFocus);
if (indexOfCentralChild != -1)
{
initialCaretPosition = this.Contents[indexOfCentralChild].InitialCaretPosition;
Contract.Assert(initialCaretPosition >= 0);
return result[(InternalIndex)indexOfCentralChild];
}
//recursive part:
for (int boxIndex = 0; boxIndex < this.Contents.Count; boxIndex++)
{
var boxSpecs = this.Contents[boxIndex];
BoxViewModel box = result[(InternalIndex)boxIndex];
ElementIndex compositionIndex = (ElementIndex)0;
foreach (var boxContent in boxSpecs.Contents)
{
var content = boxContent as CompositionConstructionSpecifier;
if (content != null)
{
var potential = content.GetCentralBox((BoxCompositionViewModel)box[compositionIndex], out initialCaretPosition);
if (potential != null)
return potential;
}
compositionIndex++;
}
}
//no box that should receive the caret was found
initialCaretPosition = -1;
return null;
}
public IEnumerable<NameInstance> GetNameInstancesAlongRouteFromRootTo(BoxCompositionViewModel boxComposition)
{
var route = GetRoute(boxComposition);
return GetNameInstancesAlongRoute(route);
}
private Stack<int> GetRoute(BoxCompositionViewModel boxComposition)
{
var result = GetRoute(boxComposition.Boxes[0]);
int dummy = result.Pop();
Contract.Assert(dummy == 0, "You probably meant to call the other GetRoute overload");
return result;
}
private CompositeNameInstance ToNameInstance(BoxCompositionViewModel newComposition, LinearPosition position)
{
//Contract.Assert(newComposition.Boxes.Count == newComposition.Arranger.Positions.Count);
Contract.AssertForAll(newComposition.Arranger.Positions, NotNull);
return new CompositeNameInstance(Enumerable.Zip(newComposition.Boxes, newComposition.Arranger.Positions, GetMutation).ToList(), position);
}
private NameInstance GetMutation(BoxCompositionViewModel newComposition, int palpableIndex)
{
//register the box composition for subsequent changes to it
newComposition.Boxes.CollectionChanged += onBoxCompositionCollectionChanged;
//create the box composition in the name instance model
var result = ToNameInstance(newComposition, new LinearPosition(palpableIndex));
//associate the box composition with the name instance model
newComposition.Model = result;
return result;
}
/// <summary> Handles creating a new box composition. </summary>
private void AddNewBoxCompositionMutation(BoxCompositionViewModel newComposition, int palpableIndex)
{
Func<IEnumerable<NameInstance>> mutation = () => GetMutation(newComposition, palpableIndex).ToSingleton();
GetCollectionToAddTo(GetRoute(newComposition.Box)).Add(palpableIndex, mutation, true);
}
/// <summary> Gets the boxes in the specified box composition in the specified direction starting from a specific box. </summary>
/// <param name="boxComposition"> The box composition whose boxes are to be yielded. </param>
/// <param name="preferredBoxIndex"> The index of the first preferred box. The box _at_ this index is yielded. </param>
/// <param name="boxesTraversalDirection"> The direction in which to get the boxes (true for right, false for left). </param>
private static IEnumerable<BoxViewModel> GetPreferredBoxes(BoxCompositionViewModel boxComposition, int preferredBoxIndex, bool boxesTraversalDirection)
{
for (int i = preferredBoxIndex; 0 <= i && i < boxComposition.Boxes.Count; i += boxesTraversalDirection ? 1 : -1)
yield return boxComposition.Boxes[i];
}