Question

I am writing a program with a lot of buttons(over 100), and each one needs a unique result, but all of the results are similar, this is the code of the first button

box1= 'filepath to text file'
def openfile(filename):
    filetxt = (open(filename,"r").read())
    return filetxt
    var.set(filetxt)

def Box1():
    var.set(openfile(box1))

openfile(box1)
window1 = Tk()
window1.geometry('450x450')

var = StringVar()

Button1 = Button(donut,text = "Box #1", command= Box1 )
Button1.pack()

each button will do the same thing, but access a different file, is there a more efficient way to do this than simply writing a unique callback function for every button?

Answer 1

Usually, you’d have the files in a list:

list_of_files = ...

Then you would create a function to make a button which opens a file input:

def file_open_button(filename):
    b = Button(donut, text = 'open {0}'.format(filename), command = lambda: openfile(filename))
    return b

Now iterate over your list of files and create the buttons, packing as you go:

for f in list_of_files:
    button = file_open_button(f)
    button.pack()

Perhaps the thing you’re missing is an understanding of lambda (anonymous) functions. a lambda function is much like a regular function:

def foo(x):
    return x*x

bar = lambda x: x*x

The above statements are very similar. e.g. foo(x) == bar(x) will always be True.