private void HistoryRenderText(Gtk.TreeViewColumn column, Gtk.CellRenderer cell, Gtk.TreeModel model, Gtk.TreeIter iter)
{
BaseHistoryItem item = (BaseHistoryItem) model.GetValue (iter, 0);
if (item.State == HistoryItemState.Undo) {
(cell as Gtk.CellRendererText).Style = Pango.Style.Normal;
(cell as Gtk.CellRendererText).Foreground = "black";
(cell as Gtk.CellRendererText).Text = item.Text;
} else if (item.State == HistoryItemState.Redo) {
(cell as Gtk.CellRendererText).Style = Pango.Style.Oblique;
(cell as Gtk.CellRendererText).Foreground = "gray";
(cell as Gtk.CellRendererText).Text = item.Text;
}
}