GObject(GTK3+) with Python

1 prerequisite.sh

$ brew install pkg-config gobject-introspection libffi gtk+3
$ export PKG_CONFIG_PATH=/usr/local/Cellar/libffi/3.2.1/lib/pkgconfig
$ export LC_ALL=en_US.UTF-8 # ko_KR.UTF-8

2 pip-install.sh

$ python3 -m venv venv
$ source venv/bin/activate
$ pip install --upgrade pip setuptools
$ pip install pycairo pygobject

3 main.glade

<?xml version="1.0" encoding="UTF-8"?>
<!-- Generated with glade 3.22.1 -->
<interface>
  <requires lib="gtk+" version="3.20"/>
  <object class="GtkWindow" id="main_window">
    <property name="can_focus">False</property>
    <child>
      <object class="GtkGrid">
        <property name="visible">True</property>
        <property name="can_focus">False</property>
        <child>
          <object class="GtkButton" id="button_hello">
            <property name="label" translatable="yes">button</property>
            <property name="visible">True</property>
            <property name="can_focus">True</property>
            <property name="receives_default">True</property>
            <signal name="pressed" handler="on_button_hello_pressed" swapped="no"/>
          </object>
          <packing>
            <property name="left_attach">0</property>
            <property name="top_attach">0</property>
          </packing>
        </child>
        <child>
          <object class="GtkButton" id="buggon_quit">
            <property name="label" translatable="yes">Quit</property>
            <property name="visible">True</property>
            <property name="can_focus">True</property>
            <property name="receives_default">True</property>
            <signal name="pressed" handler="on_button_quit_pressed" swapped="no"/>
          </object>
          <packing>
            <property name="left_attach">1</property>
            <property name="top_attach">0</property>
          </packing>
        </child>
      </object>
    </child>
  </object>
</interface>

4 main.py

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


class Handler:

    def on_button_hello_pressed(self, button):
        print('Hello')

    def on_button_quit_pressed(self, button):
        Gtk.main_quit()


if __name__ == '__main__':
    builder = Gtk.Builder()
    builder.add_from_file("main.glade")
    builder.connect_signals(Handler())

    window = builder.get_object("main_window")
    window.show_all()

    Gtk.main()