is it possible to add code to a list in python

Question

import PySimpleGUI as sg

rows_needed = 2
result = [['text1', 'text2'], ['text3']]
menu_layout = []

for x in range(0,rows_needed):
    temp = []
    try:
        temp.append(sg.Button(c) for c in result[x])
    finally:
        pass
    menu_layout.append(temp)
    print(menu_layout)
layout = [[sg.Button(c) for c in result]]
window = sg.Window('', menu_layout)

window.read()

so im attempting to create a nested list for menu layout, the result i want would be for example

menu_layout = [[sg.Button('text1'), sg.Button('text2')], [sg.Button('text3')],]

im using pysimplegui

my current code at the top gives the following result in powershell

[[<generator object menu.<locals>.<genexpr> at 0x0000016308733AE0>]]
[[<generator object menu.<locals>.<genexpr> at 0x0000016308733AE0>],
[<generator object menu.<locals>.<genexpr> at 0x0000016308733C30>]]
Traceback (most recent call last):   File
"C:\Users\cafemax\projects\POS\POS\Client_Posv2.py", line 713, in
<module>
    menu()   File "C:\Users\cafemax\projects\POS\POS\Client_Posv2.py", line 532, in menu
    window = sg.Window('', menu_layout)   File "C:\Users\cafemax\.venvs\stockcontrol\lib\site-packages\PySimpleGUI\PySimpleGUI.py",
line 9604, in __init__
    self.Layout(layout)   File "C:\Users\cafemax\.venvs\stockcontrol\lib\site-packages\PySimpleGUI\PySimpleGUI.py",
line 9783, in layout
    self.add_rows(new_rows)   File "C:\Users\cafemax\.venvs\stockcontrol\lib\site-packages\PySimpleGUI\PySimpleGUI.py",
line 9753, in add_rows
    self.add_row(*row)   File "C:\Users\cafemax\.venvs\stockcontrol\lib\site-packages\PySimpleGUI\PySimpleGUI.py",
line 9708, in add_row
    if element.ParentContainer is not None: AttributeError: 'generator' object has no attribute 'ParentContainer'

the reason im trying to do this is because i need to be able to generate a variable amount of buttons based on the size of a list so i can't hard code this.

any help on how to fix this or change must make to my append

Please develop this in isolation. In other words, extract a [mcve]. As a new user here, also read [ask] and take the [tour]. Concerning the error, it complains about a field that isn't even in the code you provide. — Ulrich Eckhardt, Aug 23 '22 at 14:31
You'll want something like `temp = [sg.Button(c) for c in result[x]]` without the try/append stuff. — AKX, Aug 23 '22 at 14:33
Okay, first question now: What's the point of the `try`/`finally`? — Ulrich Eckhardt, Aug 23 '22 at 14:41
@UlrichEckhardt i was setting it up for handling errors, and thought i would need it while iterating through a nested list. as i needed it the previous time i tried doing something similar — Physcofury, Aug 23 '22 at 14:51

score 1 · Accepted Answer · answered Aug 23 '22 at 14:39

temp doesn't contain sg.Button objects, it contains generators because that's what you appended to it. You don't want to create temp and then append the generator to it, you want to extend your list with your generator. See What is the difference between Python's list methods append and extend?

for x in range(0, rows_needed):
    temp = []
    try:
        temp.extend(sg.Button(c) for c in result[x])
    finally:
        pass
    menu_layout.append(temp)

Alternatively, you can simply create temp using a list comprehension:

for x in range(0, rows_needed):
    temp = []
    try:
        temp = [sg.Button(c) for c in result[x]]
    finally:
        pass
    menu_layout.append(temp)

I'm not sure what the try..finally is for, it doesn't seem to be doing anything, but I left it in because that's not the question you're asking.

this is the solution i came up with after AKX mentioned it, i have also removed the try/finally from it, thankyou for the answer — Physcofury, Aug 23 '22 at 14:56

is it possible to add code to a list in python

1 Answers1