Microsoft.Phone.Controls.LockablePivot.OnItemsChanged C# (CSharp) Method

        protected override void OnItemsChanged(NotifyCollectionChangedEventArgs e)
        {
            if (!_isUpdating)
            {
                if (_isLocked)
                {
                    throw new System.InvalidOperationException(
                        "Pivot Items cannot be modified when locked"
                        );
                }

                // Items have been changed, so animation information
                // will need to be recreated.
                _animInfo = null;

                base.OnItemsChanged(e);
            }
        }