Expandable and contracting frame in Tkinter

Question

Does anyone know if there is already a widget/class to handle expanding/contracting a frame based on a toggled button (checkbutton) in tkinter/ttk?

This question stems from my attempt to clean up a cluttered gui that has lots of options categorized by specific actions. I would like something along the lines of:

example found on google

However instead of just text, allow for buttons, entries, any of tkinter's widgets. If this doesn't already exist, would it be possible/useful to create a class that inherits the tkinter Frame:

import tkinter as tk
import ttk

class toggledFrame(tk.Frame):
    def __init__(self):
        self.show=tk.IntVar()
        self.show.set(0)
        self.toggleButton=tk.Checkbutton(self, command=self.toggle, variable=self.show)
        self.toggleButton.pack()
        self.subFrame=tk.Frame(self)

    def toggle(self):
        if bool(self.show.get()):
            self.subFrame.pack()
        else:
            self.subFrame.forget()

Note: this code is untested, just presenting concept

Answer 1

I am actually surprised at how close I was to getting functioning code. I decided to work on it some more and have develop a simple little class to perform exactly what I wanted (comments and suggestions on the code are welcome):

import tkinter as tk
from tkinter import ttk 


class ToggledFrame(tk.Frame):

    def __init__(self, parent, text="", *args, **options):
        tk.Frame.__init__(self, parent, *args, **options)

        self.show = tk.IntVar()
        self.show.set(0)

        self.title_frame = ttk.Frame(self)
        self.title_frame.pack(fill="x", expand=1)

        ttk.Label(self.title_frame, text=text).pack(side="left", fill="x", expand=1)

        self.toggle_button = ttk.Checkbutton(self.title_frame, width=2, text='+', command=self.toggle,
                                            variable=self.show, style='Toolbutton')
        self.toggle_button.pack(side="left")

        self.sub_frame = tk.Frame(self, relief="sunken", borderwidth=1)

    def toggle(self):
        if bool(self.show.get()):
            self.sub_frame.pack(fill="x", expand=1)
            self.toggle_button.configure(text='-')
        else:
            self.sub_frame.forget()
            self.toggle_button.configure(text='+')


if __name__ == "__main__":
    root = tk.Tk()

    t = ToggledFrame(root, text='Rotate', relief="raised", borderwidth=1)
    t.pack(fill="x", expand=1, pady=2, padx=2, anchor="n")

    ttk.Label(t.sub_frame, text='Rotation [deg]:').pack(side="left", fill="x", expand=1)
    ttk.Entry(t.sub_frame).pack(side="left")

    t2 = ToggledFrame(root, text='Resize', relief="raised", borderwidth=1)
    t2.pack(fill="x", expand=1, pady=2, padx=2, anchor="n")

    for i in range(10):
        ttk.Label(t2.sub_frame, text='Test' + str(i)).pack()

    t3 = ToggledFrame(root, text='Fooo', relief="raised", borderwidth=1)
    t3.pack(fill="x", expand=1, pady=2, padx=2, anchor="n")

    for i in range(10):
        ttk.Label(t3.sub_frame, text='Bar' + str(i)).pack()

    root.mainloop()

This code produces:

Answer 2

To my knowledge, Tkinter/ttk does no provide such widgets. You might mimic your example (expand/collapse label list) with a tkinter.ttk.Treeview.

It is perfectly acceptable¹ to develop your own widgets, and your code seems a right start.