python tkinter return value from function used in command

Question

how do i get the return value A to C? I am not using class by the way.

def button:
    mylabel = Label(myGui, text = \"hi\").grid(row = 0, column = 0)
    A          


        

Answer 1

Old question, but most answers suggested a global variable. I don't like using too many global variables in my projects, so here's my solution.

When declaring your Tkinter button, you can use a lambda function as the command. This lambda can interact with variables that are within the same namespace as the button you are defining. Be sure to define this variable before initializing the button.

def button():
    mylabel = Label(myGui, text = "hi").grid(row = 0, column = 0)
    A = B.get()
    return A

B = StringVar()
C = ""
myentry = Entry(myGui, textvariable = B).grid(row = 1, column = 0)
Submit = Button(myGui, text = "Submit", command = lambda: C=button()).grid(row = 1, column = 1)

You may need to have self as an argument for button depending on your project organization, but the concept is the same. Lambda commands are also useful for passing arguments to the button command.