CODEWITHSUNDEEP
pythontkinter
May.D
May.D

Reputation: 1910

get StringVar bound to Entry widget

I'm writing a simple GUI program, and need to load default values from an ini file. I've given names to Entry widget and can get it with nametowidget method.

However, I can't find a way to access the StringVar bound to the entry widget and update it's value. Using debugger, I can see that StringVar objects dont have a tkinter master, and they dont appear in any widget children. So is what I'm trying to do possible ? Or is there a workaround ?

Below is the concerned function.

def load_data(data_file):
    """
    Read an ini file and update related values
    :param data_file:
    :return:
    """
    conf = configparser.ConfigParser()
    try:
        conf.read(data_file)
        for section in conf.sections():
            try:
                container = SECTIONS[section]
                for key in conf[section]:
                    widget = container.nametowidget(key)
                    widget.set(conf[section][key])
            except KeyError:
                pass
    except configparser.Error as e:
        print(e)

Upvotes: 4

Views: 2482

Answers (2)

Henry Yik
Henry Yik

Reputation: 22493

You can access the name of the StringVar associated to a widget by widget["textvariable"]. Note that this is not the StringVar itself.

import tkinter as tk

root = tk.Tk()

a = tk.StringVar()
a.set(0)

b = tk.Entry(root,textvariable=a)
b.pack()

print (b["textvariable"])

root.mainloop()

Upvotes: 2

Bryan Oakley
Bryan Oakley

Reputation: 385900

Tkinter widgets have a getvar and setvar method which can be used to get and set the value of a variable by its name.

You can get the name of the variable associated with a widget using the cget method.

Example:

var = tk.IntVar()
entry = tk.Entry(..., textvariable=var)
...
varname = entry.cget("textvariable")
value = entry.getvar(varname)
entry.setvar(varname, value+1)

Upvotes: 3

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