Creating a list of buttons where each button remembers its appropriate command

Question

I have created a list and a cycle that adds new buttons to that list. The only problem is that the buttons don't seem to remember their appropriate command and always have to call back to the variable x in the cycle.

Buttons = []
for x in range(9):
    Buttons.append(Button(frame2, text = str(x+1), command = lambda : num_pressed(x+1), width = 10, height = 5))

The function num_pressed uses the variable x in the same way the text does, except that the text stays the same once it's defined but the command doesn't.

Therefore once the the buttons are created all of them the call the command for x = 8 as that is where the cycle ends. So in the end they all call the command num_pressed(9)

How do I make the command remember the value it is supposed to the same way the text does? Maybe assign some sort of value to each button and then assign the command based on that value that's stored in the button itself?

Sidenote: I haven't found a way but it should be possible to use the method .cget('text') as the text of the button coincidentally has the same value as what should be the variable used in num_pressed.

score 0 · Answer 1 · answered Feb 06 '21 at 23:58

0

This is a common problem, which has an easy solution : Give your lambda function x as an argument ! To do so, replace lambda : num_pressed(x + 1) with lambda x=x: num_pressed(x + 1) (or lambda x: num_pressed(x + 1), not sure, but cannot test it now, it's already late ... But just try, one of the two will work).

answered Feb 06 '21 at 23:58

TheEagle

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The first variant is correct! Thank you very much for your answer – Mentalist Andrew Feb 07 '21 at 00:50
@MentalistAndrew please accept an answer that helped you using the grey checkmark on the left of it. – TheEagle Feb 07 '21 at 04:33

Creating a list of buttons where each button remembers its appropriate command

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