private void AddPropertyTab(PropertyTab tab)
{
RadioToolButton rtb;
if (propertyTabs.Count == 0) {
selectedTab = tab;
rtb = new RadioToolButton (new GLib.SList (IntPtr.Zero), Stock.MissingImage);
rtb.Active = true;
}
else
rtb = new RadioToolButton ((RadioToolButton) toolbar.GetNthItem (propertyTabs.Count + FirstTabIndex - 1));
//load image from PropertyTab's bitmap
if (tab.Bitmap != null)
rtb.IconWidget = new Gtk.Image (ImageToPixbuf (tab.Bitmap));
else
rtb.IconWidget = new Gtk.Image (Stock.MissingImage, IconSize.SmallToolbar);
rtb.SetTooltip (tips, tab.TabName, null);
rtb.Toggled += new EventHandler (toolbarClick);
toolbar.Insert (rtb, propertyTabs.Count + FirstTabIndex);
propertyTabs.Add(tab);
}