void toolbarClick(object sender, EventArgs e)
{
if (sender == alphButton)
PropertySort = System.Windows.Forms.PropertySort.Alphabetical;
else if (sender == catButton)
PropertySort = System.Windows.Forms.PropertySort.Categorized;
else {
int index = toolbar.GetItemIndex ((RadioToolButton) sender) - FirstTabIndex;
PropertyTab tab = (PropertyTab) propertyTabs[index];
if (selectedTab == tab) return;
selectedTab = tab;
Populate ();
}
}