#! /usr/bin/env python3
# -*- coding: utf-8 -*-
 
import kivy
kivy.require('1.11.1')
 
from kivy.app import App
from kivy.uix.screenmanager import Screen
from kivy.uix.widget import Widget
from kivy.properties import StringProperty, ListProperty, NumericProperty
from kivy.lang import Builder
 
Builder.load_string('''
<Main>:
    BoxLayout:
        canvas.before:
            Color:
                rgb: 1, 1, 1
            Rectangle:
                size: self.size
                pos: self.pos
        canvas:
            Rectangle:
                # self.size = taille du BoxLayout
                size: self.size[0]/2, self.size[0]/2  # l'image est carrée
                pos: self.pos
                source: "labo.png"
''')
 
class Main(Screen):
    pass
 
class FondBlancApp(App):
    def build(self):
        return Main()
 
if __name__ == '__main__':
    FondBlancApp().run()