Mine

	public function sendSMS_clicked_cb() {
		$treeView = $this->glade->get_widget('addressesToSendTo');// returns GtkTreeView object
		
		$liststore = new GtkListStore(Gtk::TYPE_STRING, Gtk::TYPE_STRING);
		$treeView->set_model($liststore);
		$cellrenderer = new GtkCellRendererText();
		$column1 = new GtkTreeViewColumn('Ttitle', $cellrenderer, 'text', 0);
		$column2 = new GtkTreeViewColumn('Title2', $cellrenderer, 'text', 1);
		$treeView->append_column($colum1);
		$treeView->append_column($colum2);

		$liststore->append(array('string1', 'string2'));
	}