#!python
# -*- mode: python; Encoding: utf-8; coding: utf-8 -*-
# Last updated: <2022/03/26 21:13:13 +0900>
u"""
OptionMenu test.

* Windows10 x64 21H2 + Python 2.7.18 32bit + tkinter
* Windows10 x64 21H2 + Python 3.9.11 64bit + tkinter
"""

try:
    # Python 2.7
    import Tkinter as tk
except:
    # Python 3.x
    import tkinter as tk

OPT_KIND = [
    "Lines",
    "Boxs",
    "Rect only"
    ]

root = tk.Tk()
root.geometry("320x240")

# reserve variable
opt = tk.StringVar(root)
opt.set(OPT_KIND[0])

lbl = tk.StringVar(root)
lbl.set("Please select")

# create widget and layout
optmenu = tk.OptionMenu(root, opt, *OPT_KIND).pack(side = tk.TOP)
label = tk.Label(root, textvariable=lbl).pack(side = tk.BOTTOM)

def callback(*args):
    """set lbl value from opt."""
    v = opt.get()
    if v in OPT_KIND:
        idx = OPT_KIND.index(v)
    else:
        idx = -1
    lbl.set("Select [%s], index = %d" % (v, idx))

# Call callback when variable opt is updated
opt.trace("w", callback)

root.mainloop()