Second File Dialog to open at previous File Dialog pick

[gsal]

I have two consecutive File Dialogs
The first opens in the current directory
Then, the user browses away to some other directory and select a file there
When the user launches the second File Dialog, I would like to make it so that it starts in the directory the user browsed to a moment ago.

My attempt was to store the "last directory" in a variable, but, apparently, the variable is read only once before it is even set and, thus, it has no effect.

How to go about it?

Below is my sample code:

import os
import sys
import dearpygui.dearpygui as dpg


class FileDia():
    # widgets of interest, which we may want to keep track of via their UUIDs
    wlist = ('win', 'frame_file_text',    'frame_file_dialog',
                  'dic_exp_file_text',  'dic_exp_file_dialog')

    def __init__(self):
        self.gen = False                    # - to check whether uuid have already been generated or not
        self.tag={}                         # - dictionary of widget:tag pairs for widgets
        self.myname =  "File Dialog Test"
        self.frame_file = ""
        self.dic_exp_file = ""
        self.lastdir = ""

    def gen_uuid(self):
        """Generate UUIDs for widgets of interest."""
        if not self.gen:
            for w in self.wlist:
                self.tag[w] = dpg.generate_uuid()
            self.gen = True

    def win(self, mode=None):
        """Graphical interface"""
        self.gen_uuid()
        # file dialogs
        with dpg.file_dialog(default_path=self.lastdir, directory_selector=False, show=False,
                             callback=self.win_to_values, tag=self.tag['frame_file_dialog'], width=640, height=340):
            dpg.add_file_extension(".out", color=(255, 0, 255, 255), custom_text="[OUT]")
            dpg.add_file_extension(".*")
            dpg.add_file_extension("", color=(150, 255, 150, 255))
        with dpg.file_dialog(default_path=self.lastdir, directory_selector=False, show=False,
                             callback=self.win_to_values, tag=self.tag['dic_exp_file_dialog'], width=640, height=340):
            dpg.add_file_extension(".csv", color=(255, 0, 255, 255), custom_text="[CSV]")
            dpg.add_file_extension(".*")
            dpg.add_file_extension("", color=(150, 255, 150, 255))
        # main window
        with dpg.window(label=self.myname, width=800, height=200, tag=self.tag['win']):
            dpg.add_text("   ", show_label=False)
            with dpg.group(horizontal=True):
                dpg.add_text("One of the Frame files: ", show_label=False)
                dpg.add_input_text(callback=self.win_to_values, on_enter=True, tag=self.tag['frame_file_text'])
                dpg.add_button(label="Browse", callback=lambda: dpg.show_item(self.tag['frame_file_dialog']))
            with dpg.group(horizontal=True):
                dpg.add_text("       DIC Export file: ", show_label=False)
                dpg.add_input_text(callback=self.win_to_values, on_enter=True, tag=self.tag['dic_exp_file_text'])
                dpg.add_button(label="Browse", callback=lambda: dpg.show_item(self.tag['dic_exp_file_dialog']))

    def win_to_values(self, sender, app_data, user_data):
        if sender == self.tag['frame_file_dialog']:
            fullname = app_data['file_path_name']
            self.frame_file = fullname
            dpg.set_value(self.tag['frame_file_text'], self.frame_file)
            self.lastdir = os.path.dirname(fullname)
        if sender == self.tag['dic_exp_file_dialog']:
            fullname = app_data['file_path_name']
            self.dic_exp_file = fullname
            dpg.set_value(self.tag['dic_exp_file_text'], self.dic_exp_file)
            self.lastdir = os.path.dirname(fullname)

#
# - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
# MAIN
#

def win_callback():
    doc = FileDia()
    doc.win()

def exit_callback():
    sys.exit(0)

dpg.create_context()

filenew_tag = dpg.generate_uuid()        # tag for File -> New Control File     menu item
fileexit_tag = dpg.generate_uuid()       # tag for File -> Exit                 menu item

dpg.create_viewport(title='File Dialog Test', width=840, height=620)
with dpg.viewport_menu_bar():
    with dpg.menu(label="File"):
        dpg.add_menu_item(label="New", callback=win_callback, tag=filenew_tag)
        dpg.add_menu_item(label="Exit", callback=exit_callback, tag=fileexit_tag)

dpg.setup_dearpygui()
dpg.show_viewport()
dpg.start_dearpygui()
dpg.destroy_context()
sys.exit(0)

[gsal]

Never mind, I figured something.
Thanks.