Main.py

# disabling resizing
from kivy.config import Config
Config.set('graphics', 'resizable', 0)
Config.set('input', 'mouse', 'mouse,disable_multitouch')

from kivy.app import App
from kivy.uix.boxlayout import BoxLayout
from kivy.uix.dropdown import DropDown
from kivy.properties import StringProperty
from kivy.properties import NumericProperty
from Classes.Game import Game


class SettingsDropDownList(DropDown):
    def change_difficulty(self, key):
        main_widget.game.change_difficulty(key)


class MainWidget(BoxLayout):

    number_of_bombs = StringProperty()
    size_of_game = NumericProperty()

    def __init__(self, **kwargs):
        super(MainWidget, self).__init__(**kwargs)

        # Adding Drop down list for settings
        s_button = self.ids.SettingsButton
        self.dropdown = SettingsDropDownList()
        s_button.bind(on_release=self.dropdown.open)
        self.dropdown.bind(on_select=lambda
                           instance, x: setattr(s_button, 'text', x))

        # Game is created
        self.game = Game(self)


class MineSweeperApp(App):
    def build(self):
        # Global variable containing MainWidget object
        global main_widget
        main_widget = MainWidget()

        return main_widget


if __name__ == '__main__':
    MineSweeperApp().run()