CODEWITHSUNDEEP
pythontkinter
user3474688
user3474688

Reputation: 223

setting variables efficiently with tkinter callbacks

I need to set some variables using tkinter callbacks on a tkinter Button. So I could say (inside of a class definition) 

Button1 = Button(parentframe, text="set", command = self.setvar)

def setvar(self):
    self.myvar = 7

Is there some way to do that with an inline (lambda) function, rather than cluttering things up with silly little callbacks? 

command = lambda *args: something?

Upvotes: 0

Views: 355

Answers (2)

asongtoruin
asongtoruin

Reputation: 10359

You could do something like this using Tkinter's integer variable class and a lambda function as you suspected. A variable of type IntVar has .get() and .set() methods that will allow you to, unsurprisingly, get and set its value. Take the following for example:

from Tkinter import *


class App(Frame):
    def __init__(self, *args, **kwargs):
        Frame.__init__(self, *args, **kwargs)
        # initialise Integer Variables
        self.example1 = IntVar()
        self.example1.set(2)

        self.text1 = Entry(root, textvariable=self.example1, state=DISABLED)
        self.text1.grid(row=0, column=0)

        self.button1 = Button(root, text="Double", command=lambda: self.double_value(self.example1))
        self.button1.grid(row=1, column=0)

    def double_value(self, var):
        var.set(var.get() * 2)


root = Tk()
app = App(root)

root.mainloop()

This gives you a bit of flexibility, and could be expanded to apply the same feature to multiple buttons relating to different Entry boxes and IntVar variables.

Upvotes: 1

Novel
Novel

Reputation: 13729

You could do this: 

command = lambda: setattr(self, 'myvar', 7)

Upvotes: 1

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