Self or not Self in Widgets [closed] - object

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I run the Codes "With Self" and "Without Self" and the result is the same. Most developers prefer the "With Self" Why? What is the difference? Thanks!
# Without Self
import tkinter as tk
class MyApp():
def __init__(self, root):
w = tk.Label(root, text="Hello!", font = "Arial 36", bg='yellow')
w.pack()
root = tk.Tk()
myapp = MyApp(root)
root.mainloop()
# With self
import tkinter as tk
class MyApp():
def __init__(self, root):
self.root = root
self.w = tk.Label(self.root, text="Hello!", font = "Arial 36", bg='yellow')
self.w.pack()
root = tk.Tk()
myapp = MyApp(root)
root.mainloop()

Answer 1

Self or not Self?
Classes or no classes? Functions or no functions?
There is in my opinion no really simple, short and straightforward answer to your question. It is a matter of preferences and a matter of what one considers to be a good programming style.
Usage of classes is not strictly necessary for programming tkinter applications and I personally prefer whenever it makes sense to avoid the overhead required for coding classes. There is a good reason behind why stackoverflow tries to eliminate questions asking for opinions or preferences. This helps to avoid unnecessary vivid discussions and Style Wars.
The Python code below demonstrates that it is possible to configure a tkinter.Label without prior saving a reference to it in a class self. variable. This is possible because tkinter itself stores all of the information about created and still existing widgets and objects. The comments Try accessing the label inside another function of your class (a method) [without self] are maybe a tiny bit misleading as they assume that this is not possible and make the difference between self or not self.
In the code below along with self or not self are two more cases of programming style covered: no function or class at all, and no class but functions. Label modification after its creation is there only to help understanding tkinter and classes:
import tkinter as tk
# No class or function.
# Down to FIVE (5) lines of code:
root = tk.Tk()
tk.Label(root, text="Hello!", font = "Arial 36", bg='yellow').pack()
root.geometry('800x128')
root.winfo_children()[0].config(text="No class/function: 5 lines")
root.mainloop()
# With a class, but without self.
# There are TWELVE (12) lines of code:
class MyApp_withoutSelf():
def __init__(self):
tk.Label(root, text="Hello!", font = "Arial 36", bg='yellow').pack()
self.setWindowGeometry()
self.changeLabelText()
def setWindowGeometry(self):
root.geometry('640x128')
def changeLabelText(self):
root.winfo_children()[0].config(text="Class no self: 12 lines")
root = tk.Tk()
MyApp_withoutSelf()
root.mainloop()
# With a class and with self
# There are FOURTEEN (14) lines of code:
class MyApp_withSelf():
def __init__(self, root):
self.root = root
self.w = tk.Label(self.root, text="Hello!", font = "Arial 36", bg='yellow')
self.w.pack()
self.setWindowGeometry()
self.changeLabelText()
def changeLabelText(self):
self.w.config(text="Class with self 14 lines")
def setWindowGeometry(self):
root.geometry('640x128')
root = tk.Tk()
myapp = MyApp_withSelf(root)
root.mainloop()
# No class but functions.
# There are ELEVEN (11) lines of code:
root = tk.Tk()
def setup():
tk.Label(root, text="Hello!", font = "Arial 36", bg='yellow').pack()
setWindowGeometry()
changeLabelText()
def setWindowGeometry():
root.geometry('920x128')
def changeLabelText():
root.winfo_children()[0].config(text="No class but functions 11 lines.")
setup()
root.mainloop()