BackGround For App WIth Convas Rectangle in Laout

Back Ground App With KV

from kivy.app import App
from kivy.lang import Builder
root = Builder.load_string(’’’
FloatLayout:
canvas.before:
Color:
rgba: 0, 1, 0, 1
Rectangle:
# self here refers to the widget i.e FloatLayout
pos: self.pos
size: self.size
Button:
text: ’Hello World!!’
size_hint: .5, .5
pos_hint: {’center_x’:.5, ’center_y’: .5}
’’’)
class MainApp(App):
def build(self):
return root
if __name__ == ’__main__’:
MainApp().run()

BackGround App

from kivy.app import App
from kivy.graphics import Color, Rectangle
from kivy.uix.floatlayout import FloatLayout
from kivy.uix.button import Button




class RootWidget(FloatLayout):
  def __init__(self, **kwargs):
		super(RootWidget, self).__init__(**kwargs)
		self.add_widget(
			Button(
				text="Hello World",
				size_hint= (.5, .5),
				pos_hint={'center_x':.5,
				'center_y':.5}))
class MainApp(App):
	def build(self):
		self.root = root = RootWidget()
		root.bind(
			size=self._update_rect,
			pos=self._update_rect)
		with root.canvas.before:
			Color(0, 1, 0, 1) # green; colors range from 0-1 not 0-255
			self.rect = Rectangle(
				size=root.size,
				pos=root.pos)
		return root
	def _update_rect(self, instance, value):

		self.rect.pos = instance.pos
		self.rect.size = instance.size
if __name__ == '__main__':
	MainApp().run()