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.
Image Widget:
The Image widget is used to display an image. To use the image widget you must have to import :
from kivy.uix.image import Image, AsyncImage (not necessary while working with .kv file)
because the module kivy.uix.image have all the functionality related to images.
Images can be loaded to the Application via two types:
1) Synchronous Loading: Loading image from the system (must be from the folder in which .py and .kv file is saved)
2) Asynchronous Loading: To load an image asynchronously (for example from an external webserver)
Note: By default, the image is centered and fits inside the widget bounding box. If you don’t want that, you can set allow_stretch to True and keep_ratio to False.
Basic Approach to create multiple layout in one file:
1) import kivy
2) import kivyApp
3) import image
4) import BoxLayout
5) set minimum version(optional)
6) Create the Layout class
7) Create App class
8) Create .kv file:
1) Add BoxLayout
2) Add Label
3) Add Image
4) Resizing, Positioning etc of Image
9) return instance of the layout class
10) Run an instance of the class
So in the below code, we will explain How to load Synchronous and Asynchronous images. Also How to resize, Positioning, Label, etc the image with some more stuff.
.py file –
Python3
## Sample Python application demonstrating the ## working with images in Kivy using .kv file ################################################## # 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') # 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 # to change the kivy default settings we use this module configfrom kivy.config import Config # 0 being off 1 being on as in true / false# you can use 0 or 1 && True or FalseConfig.set('graphics', 'resizable', True)# creating the root widget used in .kv fileclass Imagekv(BoxLayout): ''' no need to do anything here as we are building things in .kv file ''' pass# class in which name .kv file must be named My.kv. class MyApp(App): # define build() function def build(self): # returning the instance of Imagekv class return Imagekv()# run the Appif __name__ == '__main__': MyApp().run() |
.kv file implementation –
Python3
# How to use images in kivy using .kv # root widget of Imagekv Class<Imagekv>: # Giving orientation to Box Layout orientation:'vertical'############################################### # Adding Box Layout BoxLayout: padding:5 # Adding image from the system Image: source: 'download.jpg' # Giving the size of image size_hint_x: 0.4 # allow stretching of image allow_stretch: True # Giving Label to images Label: text:"Python" font_size:11 bold:True Label: text:"Programming Language" font_size:10 ############################################### # Drawing the line between the multiples Label: canvas.before: Color: rgba: (1, 1, 1, 1) Rectangle: size: self.size pos: self.pos size_hint_y: None height: 1################################################ # Another Box Layout BoxLayout: padding:5 Image: source:"downloading.jpg" size_hint_x: 0.4 allow_stretch: True Label: text:"Image" font_size:11 bold:True Label: text:"Python Image" font_size:10 ############################################# # Drawing the line between the multiples Label: canvas.before: Color: rgba: (1, 1, 1, 1) Rectangle: size: self.size pos: self.pos size_hint_y: None height: 1 ############################################### # Adding next Box Layout BoxLayout: padding:5 # To load an image asynchronously # (for example from an external webserver) AsyncImage: width: 100 allow_stretch: True Label: text:" Asynchronous Image " font_size:11 bold:True Label: text:"Kivy Logo" font_size:10#################################################### # Drawing the line between the multiples Label: canvas.before: Color: rgba: (1, 1, 1, 1) Rectangle: size: self.size pos: self.pos size_hint_y: None height: 1##################################################### # LAst Box Layout BoxLayout: padding:5 AsyncImage: size_hint_y: None width: 100 allow_stretch: True Label: text:"Asynchronous Image " font_size:11 bold:True Label: text:" Webserver image " font_size:10 |
Output:
