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I'm trying to devise a tkinter gui, that, among others, lets users choose a 'working folder' and a 'destination folder (and there is more coming). I stripped the code to its bare functionality hereunder.

I found myself duplicating code for the selection of both the 'working folder' and the 'destination' folder. I came up with the solution to put these variables in a dictionary (I could pass them as mutable objects along with the lambda). Although it is a working solution, I have the feeling there is more standard way of achieving this objective.

My question therefore is: how can I make my _browsefile() function work whilst changing the value of self.working_dir and self.destination_dir, without using an artificial dictionary structure, hence avoiding duplicate code? This would implicate that I can generalize the _browsefile func somehow.

I have seen very advanced reusage features in text books, but currently this is out of my league. If I can learn to tackle this 'easy' one, it would possibly help me on my journey.

Thank you for giving me advice in doing it the Pythonic way...

import tkinter as tk
from tkinter import filedialog

class View():
    def __init__(self, parent):
        self.parent = parent
        
        self.gui_variables = {'working dir': '',
                              'destination dir': ''}
        
        self.menu()
    
    def menu(self):
        self.folder_button1 = tk.Button(self.parent, text="Choose Working Folder",
                                       command=lambda: self._browsefile(self.gui_variables['working dir']))
        self.folder_button1.pack()

        self.folder_button2 = tk.Button(self.parent, text="Choose Dest. Folder",
                                       command=lambda: self._browsefile(self.gui_variables['destination dir']))
        self.folder_button2.pack()


    def _browsefile(self, directory):
        answer = tk.filedialog.askdirectory()
        self.gui_variables[directory] = answer


if __name__ == '__main__':
    root = tk.Tk()
    View(root)
    root.mainloop()
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1
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Don't use a dictionary. You can just refer to the attrs of a class by their name. Something like:

import tkinter as tk
from tkinter import filedialog
from typing import Optional


class View:
    def __init__(self, parent: tk.Tk):
        self.parent = parent
        self.working_dir: Optional[str] = None
        self.dest_dir: Optional[str] = None

        self.menu('Working', 'working_dir')
        self.menu('Dest.', 'dest_dir')

    def menu(self, title: str, attr: str):
        def browse():
            setattr(self, attr, tk.filedialog.askdirectory())

        button = tk.Button(
            self.parent,
            text=f'Choose {title} Folder',
            command=browse,
        )
        button.pack()


if __name__ == '__main__':
    root = tk.Tk()
    View(root)
    root.mainloop()

Notes:

  • Do not add a () suffix to your class
  • Do not assign those buttons as members on your class
  • Centralize the creation of the buttons and the associated command
  • For the command handler, use a simple closure
  • To target a specific member variable, accept a parameter that's used with setattr
  • Use type hints
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  • \$\begingroup\$ Thank you for reviewing my code and for the additional advice. \$\endgroup\$ – grrfield Jan 29 at 10:40
  • \$\begingroup\$ What's wrong with using () ? \$\endgroup\$ – Cool Cloud Feb 1 at 22:36
  • 1
    \$\begingroup\$ @CoolCloud it's a Python 2 construct, not needed these days \$\endgroup\$ – Reinderien Feb 1 at 23:38
  • \$\begingroup\$ @Reinderien Oh okay, thanks for replying. \$\endgroup\$ – Cool Cloud Feb 2 at 5:35

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