Kivy content sizes adjustment

Question

I have been started to work in kivy recently. The thing what I am doing now is, i have a blank page with a button, when I click that button it navigates to an user input screen. It works fine, but the content comes in a very small input boxes and text as in the picture.

My question is that I want it bigger and centred.

Here is my code:

In python:

from kivy.app import App
from kivy.uix.label import Label
from kivy.uix.gridlayout import GridLayout
from kivy.uix.textinput import TextInput
from kivy.uix.screenmanager import ScreenManager, Screen, FadeTransition
from kivy.uix.widget import Widget
from kivy.lang import Builder

class LoginScreen(GridLayout):
    def __init__(self, **kwargs):
        super(LoginScreen, self).__init__(**kwargs)
        self.cols = 2
        self.add_widget(Label(text="Username:"))
        self.username = TextInput(multiline=False)
        self.add_widget(self.username)

        self.add_widget(Label(text="Password:"))
        self.password = TextInput(multiline=False, password=True)
        self.add_widget(self.password)

        self.add_widget(Label(text="Two Factor Auth:"))
        self.tfa = TextInput(multiline=False)
        self.add_widget(self.tfa)

class MainScreen(Screen):
    pass

class AnotherScreen(Screen):
    pass

class ScreenManagement(ScreenManager):
    pass

presentation = Builder.load_file("screen.kv")   

class SimpleKivy(App):
    def build(self):
        return presentation

if __name__ == "__main__":
    SimpleKivy().run()

In kv:

 #: import FadeTransition kivy.uix.screenmanager.FadeTransition

ScreenManagement:
    transition: FadeTransition()
    MainScreen:
    AnotherScreen:

<MainScreen>:
    name: "main"
    Button:
        color: 0,1,0,1
        font_size: 25
        size_hint: 0.3,0.2
        text: "Click"
        on_release: app.root.current = "other" 
        pos_hint: {"right":1, "top":1}      


<AnotherScreen>:
    name: "other"

    GridLayout:
        LoginScreen

Answer 1

In your screen.kv , you have the LoginScreen inside a GridLayout . Since the LoginSCreen is a GridLayout , you do not need that extra GridLayout .

Just change:

<AnotherScreen>:
    name: "other"

    GridLayout:
        LoginScreen

to:

<AnotherScreen>:
    name: "other"

    LoginScreen: