Text Input box with a verification button in kivy (using .kv file)

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.
In this article we will learn how we can add a button with the Text input in kivy using .kv file in python just like the same we have in the input and submit button. So to make this you firstly must know about Textinput widget and Button in kivy.

TextInput: The TextInput widget provides a box for editable plain text. Unicode, multiline, cursor navigation, selection and clipboard features are supported.
Button: The Button is a Label with associated actions that are triggered when the button is pressed (or released after a click/touch). We can add functions behind the button and style the button.

Basic Approach -

1) import kivy
2) import kivyApp
3) import widget
4) import Boxlayout
5) import textinput and Button
6) Set minimum version(optional)
7) Create Widget class
8) Create App class
9) create .kv file (name same as the app class):
        1) create textinput
        2) create Button
10) return Layout/widget/Class(according to requirement)
11) Run an instance of the class

Kivy Tutorial – Learn Kivy with Examples.

Implementation of the Approach
main.py file

Python3

# Program to Show how to create textinput
# with button 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('1.9.1')

# Widgets are elements
# of a graphical user interface
# that form part of the User Experience.
from kivy.uix.widget import Widget

# The TextInput widget provides a
# box for editable plain text
from kivy.uix.textinput import TextInput

# BoxLayout arranges widgets in either
# in a vertical fashion that is
# one on top of another or in a horizontal
# fashion that is one after another.
from kivy.uix.boxlayout import BoxLayout

# to change the kivy default settings we use this module config
from kivy.config import Config

# 0 being off 1 being on as in true / false
# you can use 0 or 1 && True or False
Config.set('graphics', 'resizable', True)

# creating the root widget used in .kv file
class BtnTextInput(BoxLayout):
    pass

# class in which we are creating the Textinput and btn
# in .kv file to be named main.kv
class MainApp(App):
    # defining build()
    def build(self):
        # returning the instance of root class
        return BtnTextInput()

# run function runs the whole program
# i.e run() method which calls the target
# function passed to the constructor.
if __name__ == '__main__':
    MainApp().run()

.kv file implementation

Python3

## .kv file implementation of the App class


# Creating the root widget
<BtnTextInput>:

    # To position widgetsin the proper orientation
    # use of vertical orientation to set all widgets
    orientation: "vertical"

    # Using the Box layout
    BoxLayout:
        height: "50dp"
        size_hint_y: None

        # Creating Test input
        TextInput:
            size_hint_x: 20

        # Creating Button
        Button:
            text: "Apply"
            size_hint_x: 25
            background_color: 0, 0, 1, 1
            font_size: 35

Output:
Button is pressed

Button not pressed

Simple view (Close)