How can I add text on my round rectangle and/or change the background on kivy?

Question

main:

from kivymd.app import MDApp

class DeliveryToday(MDApp):
    def build(self):
        return

DeliveryToday().run()

kv

MDScreen :
    canvas.before:
        Color:
            rgba: (.4,.4,.4,1)
        RoundedRectangle:
            size : self.width/2, self.height/3
            pos : self.center_x - self.width/4 , self.center_y - self.height/6                         
            radius: [(40, 40), (40, 40), (40, 40), (40, 40)]

I am a beginner at kivy and just started making this round rectangle. I wish to add text ON the round rectangle saying "Welcome" but am a bit confused on where and how I should add it as obviously it won't work on the canvas, or will it? (I am a tkinter person and it works on the canvas there so its a bit weird).

Also I wish to change the background of the rectangle from to blue (it is currently white) and tried a couple things there like background_color and stuff but that doesn't seem to work either.

Any advice on how I could do either of this would be appreciated. Thank you!

Answer 1

For your comment question: [am I able to add other widgets here too like a button?]

Check this code below. I set button's background_color's alpha value=.5 for you to see how it works. You need to change it's alpha to 0 and it gonna work like as button. You can design your own buttons like this way.But first, you should start to learn KivyMD for more button (&other things) styles.

from kivymd.app import MDApp
from kivy.lang import Builder
kv = Builder.load_string('''
FloatLayout:
    id: layout
    canvas.before:
        Color:
            rgba: 0,0,0,1
        Rectangle:
            size: self.size
            pos: self.pos
    canvas:
        Color:
            rgba: (0,0,1,1)
        RoundedRectangle:
            size : self.width/2, self.height/3
            pos : self.center_x - self.width/4 , self.center_y - self.height/6                         
            radius: [(40, 40), (40, 40), (40, 40), (40, 40)]
    Button:
        size_hint:None,None
        size : layout.width/2, layout.height/3
        pos : layout.center_x - layout.width/4 , layout.center_y - layout.height/6    
        background_color: 1,0,0,.5
        text: 'Welcome'
        on_release: print('Clicked Button')
''')
class DeliveryToday(MDApp):
    def build(self):
        return kv
DeliveryToday().run()

I changed boxlayout to floatlayout.Because boxlayout doesn't let me give its widgets freely positions.Other thing, changed Label to Button.Lastly i gave floatlayout an id and used it for get its position and size. You can also do this in different ways.This is one of that ways.