Why Do My Tkinter Widgets Get Stored as None

Why is Tkinter widget stored as None? (AttributeError: 'NoneType' object ...)(TypeError: 'NoneType' object ...)

widget is stored as None because geometry manager methods grid, pack, place return None, and thus they should be called on a separate line than the line that creates an instance of the widget as in:

widget = ...
widget.grid(..)

or:

widget = ...
widget.pack(..)

or:

widget = ...
widget.place(..)

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And for the 2nd code snippet in the question specifically:

widget = tkinter.Button(...).pack(...)

should be separated to two lines as:

widget = tkinter.Button(...)
widget.pack(...)

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Info: This answer is based on, if not for the most parts copied from, this answer.

Python is not storing the user's input from tkinter's Entry widget into a variable

Your input is not stored in the textvariable but in your Entry variables. Don't use the textvariable, but directly get the input from the entry widgets. turtle_bet = user_turtle_entry.get() and bet_amount = user_amount_entry.get(). You can check aftwerwards if the input was correct with an if else statement for example and even print an error if the user used a wrong input (String or Int).

Then it worked just fine for me :)

Why is Tkinter Entry's get function returning nothing?

It looks like you may be confused as to when commands are run. In your example, you are calling the get method before the GUI has a chance to be displayed on the screen (which happens after you call mainloop.

Try adding a button that calls the get method. This is much easier if you write your application as a class. For example:

import tkinter as tk

class SampleApp(tk.Tk):
    def __init__(self):
        tk.Tk.__init__(self)
        self.entry = tk.Entry(self)
        self.button = tk.Button(self, text="Get", command=self.on_button)
        self.button.pack()
        self.entry.pack()

    def on_button(self):
        print(self.entry.get())

app = SampleApp()
app.mainloop()

Run the program, type into the entry widget, then click on the button.

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