How to find out which randomly created Button has been pressed

Question

I created a working sign-out script using Python3 / tkinter. To finish it, I am trying to transfer the name of a button to a new window, then to a txt file.

In my sign-out program, when the person clicks on a category button, it opens a corresponding items.txt file and then creates a new window with a button for each item in the file. When one of the item button is clicked, a sign-out window is created with an Entry box for their name and a ‘Submit’ button. When the submit button is pressed, I want it to write the item name, person’s name, date, and time to a sign-out text file.

The answers I have found so far talk about a field of buttons that are created (like in Minesweeper).

Since these are no static buttons, I don’t know how to determine which button was pressed and what item name was assigned to that button. The names and the number of items in the file changes.

I tried to make the ‘name’ global in the button_click_pk section but it only returns the name of the last button created. I don’t know if it’s related, but it incorrectly puts the name on a different line.

Item Five

Jane Smith 2016-12-19 10:30:53

I want it to show on one line:

Item Five Jane Smith 2016-12-12 13:30:53

How do you tie a name to a button created in a for loop from a txt file?

class Writefiles:
    def __init__(self):
        global win3
        win3 = Tk()

        self.VarEnt = StringVar()

        self.lab = Label(win3, text = "Signature")
        self.lab.grid(padx = 10, pady = 10)

        self.ent = Entry(win3, font = ('Lucida Handwriting', 10), textvariable = self.VarEnt, bd = 5, width = 45)
        self.ent.focus()
        self.ent.grid(padx = 10, pady = 10)

        self.btn = Button(win3, text = 'Submit', width = 10, height = 2, background = 'gold', command = self.write_to_file)
        self.btn.grid(padx = 10, pady = 10)


    def write_to_file(self):
        date = datetime.now().strftime('   %Y-%m-%d  %H:%M:%S')

        with open('sig.txt', 'a') as f:
            f.write(name + self.ent.get() + date + '\n')
            f.close()

        win3.destroy()


def button_click_pk():   # creates the buttons from text file
    global name
    win2 = Tk()
    file = open('item.txt', 'r')
    rw = 0
    cl = 0
    for name in file:
        b1 = Button(win2, text = name, wraplength = 100, width = 18, height = 5, background = 'gold', command = Writefiles)
        b1.grid(row = rw, column = cl, padx = 11, pady = 13)
        cl += 1
        if cl == 4:
            cl = 0
            rw += 1

http://sopython.com/canon/30/why-do-my-lambda-functions-or-nested-functions-created-in-a-loop-all-use-the-las/ — Lafexlos, Dec 20 '16 at 06:54
Thank you both for the links. I had seen lambda before but I couldn’t see how it worked in my case. — poncanach, Dec 22 '16 at 17:57

score 0 · Accepted Answer · answered Dec 22 '16 at 18:02

After 2 days and MANY errors, I finally figured out that I had to make 2 lambdas. You need one in the button_click_pk function to pass it to the Class, and a second in the Class to pass it to the write_to_file function. A hint that I would need to make 2 lambdas would have made it much easier, it’s not something that is explained in any of the lambda documentation I found.

How to find out which randomly created Button has been pressed

1 Answers1