Customizing the Onscreen Keyboard in Kivy: Keyboard 02 Tutorial

Kivy is a Python framework for developing multi-touch applications. It provides tools to create custom user interfaces and is popular for developing applications for mobile devices and touch screens. One of the built-in features of Kivy is the onscreen keyboard, which allows users to input text without needing a physical keyboard. In this tutorial, we will show you how to customize the onscreen keyboard in a Kivy application.

Step 1: Setting up the environment
Before you can customize the onscreen keyboard in a Kivy application, you need to have Kivy installed on your system. You can install Kivy using pip:

pip install kivy

Once you have Kivy installed, you can start creating your application.

Step 2: Creating a Kivy application
To create a new Kivy application, you need to create a new Python file. In this file, you will define the user interface of your application using Kivy language. Here is a basic example of a Kivy application with a text input field and an onscreen keyboard:

from kivy.app import App
from kivy.uix.boxlayout import BoxLayout
from kivy.uix.textinput import TextInput

class CustomKeyboardApp(App):
    def build(self):
        layout = BoxLayout(orientation='vertical')
        self.text_input = TextInput()
        layout.add_widget(self.text_input)
        return layout

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

In this code, we have created a simple Kivy application with a horizontal BoxLayout and a TextInput widget. When you run the application, you will see a text input field on the screen.

Step 3: Customizing the onscreen keyboard
Now that you have a basic Kivy application set up, you can start customizing the onscreen keyboard. Kivy provides a built-in keyboard widget that you can use to customize the appearance and behavior of the onscreen keyboard. To do this, you need to create a custom keyboard layout and attach it to the TextInput widget.

Here is an example of how you can customize the onscreen keyboard in your Kivy application:

from kivy.uix.keyboard import Keyboard
from kivy.uix.button import Button

class CustomKeyboard(Keyboard):
    def __init__(self, **kwargs):
        super(CustomKeyboard, self).__init__(**kwargs)

        self.layout = BoxLayout(orientation='horizontal')
        self.add_widget(self.layout)

        self.layout.add_widget(Button(text='A'))
        self.layout.add_widget(Button(text='B'))
        self.layout.add_widget(Button(text='C'))

        self._key_on = True

class CustomKeyboardApp(App):
    def build(self):
        layout = BoxLayout(orientation='vertical')
        self.text_input = TextInput(keyboard_mode='managed')
        self.text_input.keyboard = CustomKeyboard()
        layout.add_widget(self.text_input)
        return layout

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

In this code, we have created a custom keyboard layout by subclassing the Keyboard class. In the __init__ method, we create a horizontal BoxLayout and add three Button widgets to it. We then set the self._key_on attribute to True to enable key events.

To attach the custom keyboard layout to the TextInput widget, we set the keyboard_mode attribute of the TextInput widget to ‘managed’ and assign an instance of our custom keyboard layout to the keyboard attribute.

When you run the application, you will see a custom onscreen keyboard with three buttons labeled A, B, and C. You can customize the appearance and behavior of the onscreen keyboard by adding more buttons or using different widgets.

Overall, customizing the onscreen keyboard in a Kivy application is a straightforward process that allows you to create a unique user experience for your users. By following the steps outlined in this tutorial, you can create a custom keyboard layout that fits the design and functionality of your application. Experiment with different layouts and widgets to create a truly custom onscreen keyboard for your Kivy application.