Stack.py

import gi

gi.require_version("Gtk", "3.0")
from gi.repository import Gtk


class StackWindow(Gtk.Window):
	def __init__(self):
		super().__init__(title="Stack Demo")
		self.set_border_width(10)

		vbox = Gtk.Box(orientation=Gtk.Orientation.VERTICAL, spacing=12)
		self.add(vbox)

		stack = Gtk.Stack()
		stack.set_transition_type(Gtk.StackTransitionType.SLIDE_LEFT_RIGHT)
		stack.set_transition_duration(1000)

		checkbutton = Gtk.CheckButton(label="Click me!")
		stack.add_titled(checkbutton, "check", "Check Button")

		label = Gtk.Label()
		label.set_markup("<big>A fancy label</big>")
		stack.add_titled(label, "label", "A label")

		stack_switcher = Gtk.StackSwitcher()
		stack_switcher.set_stack(stack)
		vbox.pack_start(stack_switcher, True, True, 0)
		vbox.pack_start(stack, True, True, 0)


win = StackWindow()
win.connect("destroy", Gtk.main_quit)
win.show_all()
Gtk.main()