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 Desktop applications.
Scroll view:
The ScrollView widget provides a scrollable/pannable viewport that is clipped at the scrollview’s bounding box. Scroll view accepts only one child and applies a window to it according to 2 properties:
- scroll_x
- scroll_y
To determine if the interaction is a scrolling gesture, these properties are used:
- scroll_distance: the minimum distance to travel, defaults to 20 pixels.
- scroll_timeout: the maximum time period, defaults to 55 milliseconds.
Note:
To use the scrollview you must have to import it:
from kivy.uix.scrollview import ScrollView
Basic Approach: 1) import kivy 2) import kivyApp 3) import scroll view 4) import string property 5) Set minimum version(optional) 6) create the scroll view class 7) Build the .kv file within the .py file 8) Run an app
Implementation of the code:
Python3
# Program to explain how to use scroll view in kivy # import kivy module import kivy # base Class of your App inherits from the App class. # app:always refers to the instance of your application from kivy.app import App # this restrict the kivy version i.e # below this kivy version you cannot # use the app or software kivy.require('1.9.0')# The Label widget is for rendering textfrom kivy.uix.label import Label# The ScrollView widget provides a scrollable viewfrom kivy.uix.scrollview import ScrollView# Property that represents a string valuefrom kivy.properties import StringProperty# Static main function that starts the application loop.from kivy.base import runTouchApp# Builder is a global Kivy instance used in# widgets that you can use to load other# kv files in addition to the default ones.from kivy.lang import Builder# Build the .kv fileBuilder.load_string('''# Define the scroll view<ScrollableLabel>: text: 'You are learning Kivy' * 500 Label: text: root.text font_size: 50 text_size: self.width, None size_hint_y: None height: self.texture_size[1]''')# Define scrollview classclass ScrollableLabel(ScrollView): text = StringProperty('')# run the ApprunTouchApp(ScrollableLabel()) |
Output:
You can also change color of ScrollBar and its width as shown below code but for that, you have to use properties of ScrollView like
- bar_color: It requires a list in RGB format for specifying bar color
- bar_width: It requires a number for specifying the bar size
Code For Changing Bar Color and Bar width:
Python3
from kivy.app import App# importing builder from kivyfrom kivy.lang import Builder# this is the main class which will# render the whole applicationclass uiApp(App): # method which will render our application def build(self): return Builder.load_string( BoxLayout: size_hint: (1, 1) ScrollView: # here we can set bar color bar_color: [0, 0, 255, 1] # here we can set bar width bar_width: 12 BoxLayout: size: (self.parent.width, self.parent.height-1) id: container orientation: "vertical" size_hint_y: None height: self.minimum_height canvas.before: Color: rgba: rgba("#50C878") Rectangle: pos: self.pos size: self.size Label: size_hint: (1, None) height: 300 markup: True text: "[size=78]GeeksForGeeks[/size]" Label: size_hint: (1, None) height: 300 markup: True text: "[size=78]GeeksForGeeks[/size]" Label: size_hint: (1, None) height: 300 markup: True text: "[size=78]GeeksForGeeks[/size]" Label: size_hint: (1, None) height: 300 markup: True text: "[size=78]GeeksForGeeks[/size]" )# running the applicationuiApp().run() |
Output:
