Python | Animation 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.

👉🏽 Kivy Tutorial – Learn Kivy with Examples.

Animation:

Animation and AnimationTransition are used to animate Widget properties. You must specify at least a property name and target value. To use Animation, follow these steps:

• Setup an Animation object
• Use the Animation object on a Widget

To use animation you must have to import:
from kivy.animation import Animation

Basic Approaches: 

1) import kivy
2) import kivyApp
3) import Button
4) import Animation
5) set kivy version (optional)
6) Create the App class
7) Define animation
8) Add animations
9) Run the App

Implementation of the Approach:

# Widget animation in kivy


# import kivy module
import kivy

# 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

# To work with Animation you must have to import it
from kivy.animation import Animation

# The Button is a Label with associated
# actions that are triggered when the button
# is pressed (or released after a click/touch).
from kivy.uix.button import Button

# Create the App class
class TestApp(App):

   # Defining the function in which animations are added

    def animate(self, instance):
        # create an animation object. This object could be stored
        # and reused each call or reused across different widgets.
        # += is a sequential step, while &= is in parallel
        animation = Animation(pos =(100, 100), t ='out_bounce')
        animation += Animation(pos =(200, 100), t ='out_bounce')
        animation &= Animation(size =(500, 500))
        animation += Animation(size =(100, 50))

        # apply the animation on the button, passed in the "instance" argument
        # Notice that default 'click' animation (changing the button
        # color while the mouse is down) is unchanged.
        animation.start(instance)

    def build(self):
        # create a button, and  attach animate()
        # method as a on_press handler
        button = Button(size_hint =(None, None), text ='plop',
                        on_press = self.animate)
        return button

# run the App
if __name__ == '__main__':
    TestApp().run()

Output:

When the Button as shown in the image when you click on it it shows the different animation.