"""
A module to show off inheritance in Kivy

Author: Walker M. White (wmw2)
Date:   October 28, 2017 (Python 3 Version)
"""

import kivy
import kivy.app
import kivy.uix.label
from kivy.config import *
from kivy.metrics import dp

# ALL applications inherit from kivy.app.App
class MyApp(kivy.app.App):
    """
    A class is a window with 'Hello World!' inside
    
    INSTANCE ATTRIBUTE:
        _label: text display in window [kivy.uix.label.Label]
    """

    # Override the build method (not __init__) to add buttons, etc.
    def build(self):
        """
        Builds the application with a single internal panel
        """
        Config.set('graphics', 'width', '400')
        Config.set('graphics', 'height', '400')
        self._label = kivy.uix.label.Label(size=(400,400), text='Hello World!', font_size=dp(36), bold=True)
        return self._label
    

# Script Code.
if __name__ == '__main__':
    MyApp().run()