Sliders For Kivy – Python Kivy GUI Tutorial #25

In this video we’ll learn how to create Sliders for Kivy and Python.

Slider for Kivy are incredibly easy to create. You just define them in your .kv file, add a min and max value, then create an on_value function to do, whatever you want the slider to do.

In this video we’ll just output the value of the slider to the screen (numbers between 1 and 50). We’ll also increase the font size of our label to whatever our Slider value is.

Python Code: slider.py
GitHub Code: slider.py

from kivy.app import App
from kivy.uix.widget import Widget
from kivy.properties import ObjectProperty
from kivy.lang import Builder
#from kivy.uix.slider import Slider

# Designate Our .kv design file 
Builder.load_file('slider.kv')

class MyLayout(Widget):
	def slide_it(self, *args):
		#print(args[1])
		self.slide_text.text = str(int(args[1]))
		self.slide_text.font_size = str(int(args[1]) * 5)


class AwesomeApp(App):
	def build(self):
		return MyLayout()

if __name__ == '__main__':
	AwesomeApp().run()

Kivy Design Code: slider.kv
GitHub Code: slider.kv

<MyLayout>
	slide_text: slider_label
	BoxLayout:
		orientation: "vertical"
		size: root.width, root.height
	
		Label: 
			id: slider_label
			text: "Slide The Slider!"
			font_size: 32

		Slider:
			min: 1
			max: 50
			step: 1
			orientation: "horizontal"
			on_value: root.slide_it(*args)