#!/usr/bin/env python3

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

class MyWindow(Gtk.Window):

    def __init__(self):
        Gtk.Window.__init__(self, title = "Hello World!")

        self.box = Gtk.Box(orientation = Gtk.Orientation.VERTICAL, spacing = 6)
        self.add(self.box)

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

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

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

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

window = MyWindow()
window.connect("delete-event", Gtk.main_quit)
window.show_all()

Gtk.main()