Kivy: StackLayout test case

stacktest.py

#import pydevd; pydevd.settrace('localhost', port=51514, suspend=False)

import sys
orientation = 'lr-tb'
if 'vertical' in sys.argv:
    sys.argv.remove('vertical')
    orientation = 'tb-lr'

from kivy.app import App
from kivy.uix.button import Button
from kivy.uix.stacklayout import StackLayout
from kivy.lang import Builder

# Buttons don't display properly when the size is too small, so
#   we'll test by rendering rectangles instead
Builder.load_string('''
<-Button>:
    canvas.before:
        Color:
            r: 1 if root.text in ('A', 'B') else 0
            g: 1 if root.text in ('B', 'C') else 0
            b: 1 if root.text in ('C', 'D') else 0
            a: 1
        Rectangle:
            pos: self.pos
            size: self.size
''')


class RootWidget(StackLayout):

    def __init__(self, **kw):
        super(RootWidget, self).__init__(orientation=orientation, **kw)
        self.spacing = 80
        self.padding = 80
        open_size = .4
        #open_size = 1./3.
        size_full = (1, open_size) if orientation == 'lr-tb' else (open_size, 1)
        size_half = (.5, open_size) if orientation == 'lr-tb' else (open_size, .5)
        a = Button(text='A', size_hint=size_full)
        b = Button(text='B', size_hint=size_half)
        c = Button(text='C', size_hint=size_half)
        d = Button(text='D', size_hint=size_full)
        self.add_widget(a)
        self.add_widget(b)
        self.add_widget(c)
        self.add_widget(d)


class GameApp(App):

    def build(self):
        rw = RootWidget()
        return rw


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