def _button_clicked(self, button):
self._calendar_window = ga_Gtk.Window(ga_Gtk.WindowType.TOPLEVEL)
self._calendar_window.set_type_hint(ga_Gdk.WindowTypeHint.DIALOG)
self._calendar_window.set_modal(True)
self._calendar_window.set_title(_("Date Selection"))
self._calendar.select_month(self._date.month - 1, self._date.year)
self._calendar.select_day(self._date.day)
vbox = ga_Gtk.VBox(spacing=3)
vbox.set_border_width(2)
vbox.pack_start(self._calendar, True, True, 0)
button_box = ga_Gtk.HButtonBox()
button_box.set_layout(ga_Gtk.ButtonBoxStyle.END)
vbox.pack_start(button_box, True, True, 0)
button = ga_Gtk.Button(_("Today"))
button.connect("clicked", self._today_clicked)
button_box.pack_start(button, True, True, 0)
frame = ga_Gtk.Frame()
frame.add(vbox)
self._calendar_window.add(frame)
self._calendar_window.set_position(ga_Gtk.WindowPosition.MOUSE)
self._calendar_window.show_all()
self._calendar.connect("day-selected-double-click",
self._calendar_clicked)