Change button Color in Kivy

Kivy is a platform independent GUI tool in Python. As it can be run on Android, IOS, Linux and Windows, etc. It is basically used to develop the Android application, but it does not mean that it can not be used on Desktops applications.

In this article, we will learn about how to change the button color in kivy. There is a property named background_color which is used to change the color of the button in kivy python .

background_color – The background-color kivy property sets the background color of an element. It is specified as a single color value.

Syntax: background_color: 1, 0, 0, 1

Note: By default the color of button is black (little grey) if you want to change it then we use this property.and it only takes the value between 0 to 1 any other value given will lead to misbehaving of program.

Basic Approach to follow while changing button color:
1) import kivy
2) import kivyApp
3) import all needed
4) set minimum version(optional)
5) Add widgets
6) Add buttons at set their colors
6) Extend the class
7) Return layout
8) Run an instance of the class

Kivy Tutorial – Learn Kivy with Examples.

Now below is the code how can you change the color of button:

Code 1#

def build(self):
        # use a (r, g, b, a) tuple
        btn = Button(text ="Push Me !",
        font_size ="20sp",

                # Here you can give the color
                # The value must be between 0 to 1
                # greyish black color
                background_color =(1, 1, 1, 1),

                size =(32, 32),
                size_hint =(.2, .2),
                pos =(300, 250))

        return btn

Code #2

## Sample Python application demonstrating the
## How to change button color in Kivy.
###################################################

# import kivy module
import kivy

# to choose the colors randomly
# every time you run it shows different color
import random

# this restricts the kivy version i.e
# below this kivy version you cannot
# use the app or software
kivy.require("1.9.1")

# base Class of your App inherits from the App class.
# app:always refers to the instance of your application
from kivy.app import App

# creates the button in kivy
# if not imported shows the error
from kivy.uix.button import Button

# BoxLayout arranges children in a vertical or horizontal box.
# or help to put the children at the desired location.
from kivy.uix.boxlayout import BoxLayout

# declaring the colours you can use directly also
red = [1, 0, 0, 1]
green = [0, 1, 0, 1]
blue = [0, 0, 1, 1]
purple = [1, 0, 1, 1]

# class in which we are creating the button
class ChangeColorApp(App):

    def build(self):
        superBox = BoxLayout(orientation ='vertical')

        HB = BoxLayout(orientation ='horizontal')

        # creating the list of defined colors
        colors = [red, green, blue, purple]


        # Changing the color of buttons
        # here you can see how you can change the color
        btn1 = Button(text ="One",
                    # Color of button is changed not default
                    background_color = random.choice(colors),
                    font_size = 32,
                    size_hint =(0.7, 1))

        btn2 = Button(text ="Two",
                    background_color = random.choice(colors),
                    font_size = 32,
                    size_hint =(0.7, 1))

        HB.add_widget(btn1)
        HB.add_widget(btn2)


        VB = BoxLayout(orientation ='vertical')

        btn3 = Button(text ="Three",
                    background_color = random.choice(colors),
                    font_size = 32,
                    size_hint =(1, 10))

        btn4 = Button(text ="Four",
                    background_color = random.choice(colors),
                    font_size = 32,
                    size_hint =(1, 15))


        VB.add_widget(btn3)
        VB.add_widget(btn4)

        superBox.add_widget(HB)
        superBox.add_widget(VB)

        return superBox

# creating the object root for App class
root = ChangeColorApp()

# run function runs the whole program
# i.e run() method which calls the
# target function passed to the constructor.
root.run()

Output: