/// <summary> Gets the box the caret can move to from the glyph run next to the box composition to move into. </summary>
private static BoxViewModel getBoxInto(InputCommandParameter caretState, bool boxesTraversalDirection)
{
//Contract.Assert(caretState.CurrentBox.Elements[caretState.Caret.position.ElementIndex] == caretState.GlyphRun);
ElementIndex boxCompositionIndex = caretState.Caret.position.ElementIndex + (boxesTraversalDirection ? 1 : -1); //update 2-June-15:
if (boxCompositionIndex < 0 || boxCompositionIndex >= caretState.CaretBox.Elements.ElementCount) //these two requirements can probably be performed by the new
return null; //CanExecuteRequirements (CaretAtBoxCompositionStart/End)
//
BoxCompositionViewModel boxComposition = caretState.CaretBox.Elements[boxCompositionIndex] as BoxCompositionViewModel; //But this works, so why change it now...
if (boxComposition == null) //
return null; //
return GetPreferredBoxes(boxComposition, boxesTraversalDirection ? 0 : (boxComposition.Count - 1), boxesTraversalDirection).FirstOrDefault(box => box.Modifiable);
}
/// <summary> Gets the box the caret can move to from an adjacent box in the same box composition. </summary>
private static BoxViewModel getAdjacentBox(InputCommandParameter caretState, bool boxesTraversalDirection)
{
//Contract.Assert(caretState.CurrentBox.Elements[caretState.Caret.position.ElementIndex] == caretState.GlyphRun);
var boxComposition = caretState.CaretBox.BoxParent;
Contract.Assert(boxComposition != null);
var result = GetPreferredBoxes(boxComposition, boxComposition.Boxes.IndexOf(caretState.CaretBox), boxesTraversalDirection).Skip(1/*skips current box*/).FirstOrDefault(box => box.Modifiable);
return result;
}
/// <summary> Focuses on the box parent in the specified direction. </summary>
/// <param name="caretState"> The box parent of the box composition this glyphrun is in, will be focused on. </param>
/// <param name="traversalDirection"> The direction in which the caret moves out of the box (true for right, false for left). </param>
private static void boxOut(InputCommandParameter caretState, bool traversalDirection)
{
Contract.Requires(!caretState.CaretBox.IsRoot);
Contract.Requires(caretState.CaretBox.BoxParent != null);
BoxCompositionViewModel parentBoxComposition = caretState.CaretBox.BoxParent;
BoxViewModel parentBox = parentBoxComposition.Box;
ExplicitIndex newCaretIndex = new ExplicitIndex(parentBoxComposition, traversalDirection ? InternalIndex.Last : InternalIndex.First);
parentBox.Focus(newCaretIndex);
}