/// <summary>
/// Inserts the visual child.
/// And invalidates all impacted measures
/// </summary>
/// <param name="node">The node.</param>
/// <param name="index">The index.</param>
public void InsertVisualChild(FlatNode node, int index)
{
VisualChildren.Insert(index, node);
for (int i = index + 1; i < VisualChildren.Count; i++)
{
VisualChildren[i]._childOffset++;
}
AdjustAncestorsSize(+1);
}
//--------------------------------------------------------------
#region Methods
//--------------------------------------------------------------
private void OnChildrenChanged(object sender, CollectionChangedEventArgs <UIControl> eventArgs)
{
// Children are also stuffed into the VisualChildren. Both collections should use
// the same order.
// Handle moved items.
if (eventArgs.Action == CollectionChangedAction.Move)
{
// Move visual children too.
VisualChildren.Move(eventArgs.OldItemsIndex, eventArgs.NewItemsIndex);
return;
}
// Handle removed items.
foreach (var oldItem in eventArgs.OldItems)
{
VisualChildren.Remove(oldItem);
}
// Handle new items.
int newItemsIndex = eventArgs.NewItemsIndex;
if (newItemsIndex == -1)
{
// Append items.
foreach (var newItem in eventArgs.NewItems)
{
VisualChildren.Add(newItem);
}
}
else
{
// Make sure that the same order is used in both collections.
foreach (var newItem in eventArgs.NewItems)
{
VisualChildren.Insert(newItemsIndex, newItem);
newItemsIndex++;
}
}
InvalidateMeasure();
}
