/// <summary>
/// Handler called every time a state is inserted in the controller.
/// </summary>
/// <param name="operation">Details of the operation performed.</param>
private protected override void OnStateInserted(WriteableInsertNodeOperation operation)
{
base.OnStateInserted(operation);
IFocusNodeState ChildState = ((FocusInsertNodeOperation)operation).ChildState;
Debug.Assert(ChildState != null);
Debug.Assert(StateViewTable.ContainsKey(ChildState));
IFocusBrowsingCollectionNodeIndex BrowsingIndex = ((FocusInsertNodeOperation)operation).BrowsingIndex;
Debug.Assert(ChildState.ParentIndex == BrowsingIndex);
MoveFocusToState(ChildState);
}
/// <summary>
/// Checks if an existing item can be removed at the focus.
/// </summary>
/// <param name="inner">Inner to use to remove the item upon return.</param>
/// <param name="index">Index of the item to remove upon return.</param>
/// <returns>True if an item can be removed at the focus.</returns>
public virtual bool IsItemRemoveable(out IFocusCollectionInner inner, out IFocusBrowsingCollectionNodeIndex index)
{
inner = null;
index = null;
bool IsRemoveable = false;
IFocusNodeState State = Focus.CellView.StateView.State;
if (Focus.CellView.Frame is IFocusInsertFrame AsInsertFrame)
{
IsRemoveable = false;
}
else
{
IsRemoveable = false;
// Search recursively for a collection parent, up to 4 levels up.
for (int i = 0; i < 4 && State != null; i++)
{
if (State.ParentInner is IFocusCollectionInner AsCollectionInner)
{
inner = AsCollectionInner;
index = State.ParentIndex as IFocusBrowsingCollectionNodeIndex;
Debug.Assert(index != null);
if (Controller.IsRemoveable(inner, index))
{
IsRemoveable = true;
break;
}
}
State = State.ParentState;
}
}
return(IsRemoveable);
}
/// <summary>
/// Checks if an existing item at the focus can be moved up or down.
/// </summary>
/// <param name="direction">Direction of the move, relative to the current position of the item.</param>
/// <param name="inner">Inner to use to move the item upon return.</param>
/// <param name="index">Index of the item to move upon return.</param>
/// <returns>True if an item can be moved at the focus.</returns>
public virtual bool IsItemMoveable(int direction, out IFocusCollectionInner inner, out IFocusBrowsingCollectionNodeIndex index)
{
inner = null;
index = null;
bool IsMoveable = false;
IFocusNodeState State = Focus.CellView.StateView.State;
if (Focus.CellView.Frame is IFocusInsertFrame AsInsertFrame)
{
IsMoveable = false;
}
else
{
IsMoveable = false;
// Search recursively for a collection parent, up to 3 levels up.
for (int i = 0; i < 3 && State != null; i++)
{
IFocusCollectionInner ListInner = null;
if (State.ParentInner is IFocusBlockListInner AsBlockListInner)
{
ListInner = AsBlockListInner;
}
else if (State.ParentInner is IFocusListInner AsListInner && IsDeepestList(State))
{
ListInner = AsListInner;
}
if (ListInner != null)
{
inner = ListInner;
index = State.ParentIndex as IFocusBrowsingCollectionNodeIndex;
Debug.Assert(index != null);
if (Controller.IsMoveable(inner, index, direction))
{
IsMoveable = true;
}
break;
}
State = State.ParentState;
}
}
return(IsMoveable);
}
