Python Tkinter - Passing Values With A Button

How do I pass parameters to a function through a button? variable = str() def RandomFunction(variable): print (variable) EntryBox = Entry(MainWindow, textvariable = variab

Solution 1:

The other answers here work, but like a lot of things in life, there's more than one way to do what you're trying to do.

The code in your question actually mixes a couple of methods of getting data from the Entry widget. You're using textvariable and lambda, but you only need one. It seems like lambda has been covered, so here's a quick answer about textvariable:

First, you need to make your variable of a Tkinter string type like this:

variable = StringVar()

Your entry widget is fine, it's connected to the StringVar(). Your button doesn't need lambda, though, because you don't need to pass an argument to your RandomFunction().

FunctionCall = Button(MainWindow, text='Enter', command=RandomFunction).pack()

Lastly, your function needs a little rework, because it's not taking an argument anymore, it's just going to use the .get() method on your StringVar() whenever it's called:

def RandomFunction():
    print(variable.get())

You can read more about StringVar()s here: http://effbot.org/tkinterbook/variable.htm

Solution 2:

You use .get() to get the contents of an Entry. From the effbot page http://effbot.org/tkinterbook/entry.htm

from Tkinter import *

master = Tk()

e = Entry(master)
e.pack()
e.focus_set()

def callback():
    print e.get()

b = Button(master, text="get", width=10, command=callback)
b.pack()

master.mainloop()

Solution 3:

Using lambda to create a function that calls the function with the argument is fine (as long as you do it correctly):

FunctionCall = Button(MainWindow, text="Enter", command=lambda: RandomFunction(EntryBox.get))

Python will be happy with this because the lambda doesn't take any arguments.