python / kivy .kv file wont read

Question

I have just started learning to program I have a really basic App based on a pong game tutorial on the kivy.org site but I must have a basic flaw that I can't see as when I run the program all I am getting is a blank screen rather than the expected canvas and labels. Please help me to waste less time on basics!

from kivy.app import App
from kivy.uix.button import Button
from kivy.uix.widget import Widget

class Singularity(Widget):
    pass

class SingularityApp(App):
    def build(self):
        return Singularity()

if __name__ in ('__main__', '__android__'):
    SingularityApp().run()

and the singularity.kv:

#:kivy 1.9.0

<Singularity>:    
    canvas:
        Rectangle:
            pos: self.center_x - 5, 0
            size: 10, self.height

    Label:
        font_size: 70  
        center_x: root.width / 4
        top: root.top - 50
        text: "0"

    Label:
        font_size: 70  
        center_x: root.width * 3 / 4
        top: root.top - 50
        text: "0"

Answer 1

• Check whether your MainApp(App) class name is same as your .kv file name without the 'App' (if not make them same) It's not case sensitive. for example: MaNagerApp(App) will load manager.kv

OR

• If you don't want to change name then simply add self.load_kv(your_kv_file_name).

Like this:

def build(self):
    self.load_kv('singularity.kv')
    return Singularity()