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KivyMD without using kv file

I'm trying to make an expense tracker app using KivyMD. I have built it already using kivy but it's design is awful, then i found out KivyMD and now i want to tweak the app using KivyMD but i want to do it without using a kv file because my app has a lot of nested if statements which are too complex to write in the kv file. Anyway, i'm trying to test KivyMD but running into this nasty ValueError
ValueError: KivyMD: App object must be initialized before loading root widget. See https://github.com/kivymd/KivyMD/wiki/Modules-Material-App#exceptions and idk how to fix it without using a kv file. This question is asked plenty times but every answer uses a kv file. Can someone please help me understand this error and tackle it without kv. Thank you... Here is some code
from kivymd.app import MDApp
from kivy.uix.boxlayout import BoxLayout
from kivy.uix.button import Button
from kivy.app import App
from kivymd.uix.boxlayout import MDBoxLayout
from kivymd.uix.stacklayout import MDStackLayout
from kivymd.uix.button import MDRaisedButton, MDRectangleFlatButton
from kivy.metrics import dp,sp
from kivymd.uix.screen import MDScreen
from kivy.uix.textinput import TextInput
from kivymd.uix.textfield import MDTextField
from kivy.uix.screenmanager import ScreenManager
import re
#ALL SCREENS
class MainScreen(MDScreen):
def __init__(self, **kwargs):
super().__init__(**kwargs)
box = MDBoxLayout(orientation="vertical")
b = MDRaisedButton(text="Content",size_hint = (1,0.5))
box.add_widget(b)
t = MDTextField(size_hint=(1,0.5))
box.add_widget(t)
self.add_widget(box)
#ScreenManager
sm = ScreenManager()
sm.add_widget(MainScreen(name="main_screen"))
class MyApp(MDApp):
def build(self):
self.theme_cls.primary_palette = "DeepOrange"
self.theme_cls.accent_palette = "Lime"
return MainScreen()
if __name__ == "__main__":
MyApp().run()
works perfectly fine when i remove the screenmanager and just return the MainScreen.
Any help or guidance is highly appreciated.

Unable to change kivy icon

I'm trying to change icon from kivy default one to some ico/png file that i provide
But it seems to be not working
I get this
Code:
from kivymd.app import MDApp
from kivy.lang import Builder
KV="""
Button:
text:""
"""
class Main(MDApp):
def build (self):
self.icon="image.png"
return Builder.load_string(KV)
Main().run()
Update:
Fixed the problem by changing the png,
But it still shows kivy logo for the loading screen ,is there any fix for this.???

First character not getting printed in kivy

I am learning to code in Kivy using python
But my Label is not showing the first character
Can anyone help me
The kv File is as follows:
<MyGrid>
Label:
text: "Techy Matanhelia"
The python file is as Follows:
from kivy.app import App
from kivy.uix.button import Button
from kivy.uix.gridlayout import GridLayout
from kivy.uix.textinput import TextInput
from kivy.uix.label import Label
from kivy.uix.widget import Widget
class MyGrid(Widget):
pass
class MyApp(App):
def build(self):
return MyGrid()
if __name__ == '__main__':
MyApp().run()
Also Can anyone tell me how to edit kivy files on pycharm2020.2.2

That is because your MyGrid class extends Widget. A simple Widget has no capability to handle positioning or sizing of its children, so the Label gets assigned the default size of (100,100) and the default position of (0,0). which results in the first letter of the Label being off the screen. Try making MyGrid extend a Layout, perhaps like this:
class MyGrid(FloatLayout):
pass

Why does a syntax error show up near <MyGrid> when I run my kv file?

I just started trying out kivy developing and ran into a problem. When I try to run a simple kivy file with a corresponding python file, it emits a syntax error. does anyone know why this happened? FYI I'm using Atom IDE with python 3.8.3, when I ran kivy based on python, it worked flawlessly, but when I try to run a rewritten kv code, it won't run.
Here's the python source code:
import kivy
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.button import Button
from kivy.uix.widget import Widget
class MyGrid(Widget):
pass
class MyApp(App):
def build(self):
return MyGrid()
if __name__ == "__main__":
MyApp().run()
...and the kv code:
< MyGrid >
Label:
text: "example text"
Error details:
File "C:\Users\ljhub\Code Storage\Python Projects\my.kv", line 1
<MyGrid>
^
SyntaxError: invalid syntax

The corrected kv file should be as below:
<MyGrid>:
Label:
text: "example text"

You have to add a colon after any declaration in kv language.
such as:
<MyGrid>:
or
Label:

How to pass arguments to build() in kivy?

I have written a code with GridLayout which need to be added with buttons in Python file. So, the add_widget() mainpulation should be done in build(). I am getting errors and couldn't get it.Someone Please help me.
In short, instead of add_btn(), I need it in build() of MineApp class.
Thanks in advance.`
main.py
from kivy.app import App
from kivy.uix.gridlayout import GridLayout
from kivy.uix.widget import Widget
from kivy.uix.button import Button
from kivy.properties import ObjectProperty
from kivy.uix.boxlayout import BoxLayout
class MainLayout(BoxLayout):
def build(self):
pass
def add_btn(self,id):
for i in range(100):
id.add_widget(Button())
class MineApp(App):
def build(self):
return MainLayout()
if __name__ == '__main__':
MineApp().run()
mine.kv file:
<MainLayout>:
orientation:'vertical'
BoxLayout:
orientation:'horizontal'
height: '30px'
size_hint_y:None
TextInput:
id: tinput
text:'10'
Button:
text:'start'
on_press:root.add_btn(grid)
Label:
id:mylabel
text:'0'
GridLayout:
id: grid
cols:10
rows:10

It took some time but think I get what you're trying to say! You can get the same effect by passing the id parameter of Grid in the .py file like so...
class MainLayout(BoxLayout):
def build(self):
for i in range(100):
self.ids.grid.add_widget(Button())
Then, you can just take your start button and...
Button:
text:'start'
on_press:root.build()
This works because "self" in .py refers to the class while in the .kv a similar wording would be 'root' (while 'self' in .kv refers to the widget!) Is this what you kind of had in mind? Let me know! I tried it out myself and had no problem running it through :)
Also, it wasn't put explicitly here that to test the code you'd need to import Builder via:
from kivy.lang import Builder
and do...
Builder.load_file("mine.kv")
as your .py and .kv don't share the same name (which you'd still need to add a "#File name: main.py" to the .kv if they did match names! Other than that, it looks good!