private void OnBookSelectionChanged(object sender, EventArgs e)
{
//prevent trying to save this page in whatever comes next
var wasNull = _domForCurrentPage == null;
_domForCurrentPage = null;
_currentlyDisplayedBook = null;
_templatePagesDict = null;
if (Visible)
{
_view.ClearOutDisplay();
if (!wasNull)
_view.UpdatePageList(false);
}
}