gui_03.py

import tkinter
from tkinter import simpledialog
from tkinter import ttk

from queue import Queue

class ProgressDialog(simpledialog.SimpleDialog):
    def __init__(self, master, text='', title=None, class_=None):
        super().__init__(master=master, text=text, title=title, class_=class_)
        self.default = None
        self.cancel = None

        self._queue = Queue()
        self._bar = ttk.Progressbar(self.root, orient="horizontal", 
                                    length=200, mode="determinate")
        self._bar.pack(expand=True, fill=tkinter.X, side=tkinter.BOTTOM)
        self.root.attributes("-topmost", True)
        self.root.after(200, self._update)

    def set_progress(self, value):
        self._queue.put(value)

    def _update(self):
        while self._queue.qsize():
            try:
                self._bar['value'] = self._queue.get(0)
            except Queue.Empty:
                pass
        self.root.after(200, self._update)




if __name__ == '__main__':
    root = tkinter.Tk()
    root.withdraw()

    p = ProgressDialog(master=root, text='Downloading Something...',
                       title='Download')

    import threading
    def _do_progress():
        import time
        for i in range(1, 11):
            time.sleep(0.5)
            p.set_progress(i*10)
        p.done(0)
    t = threading.Thread(target=_do_progress)
    t.start()
    
    p.go()
    print('Download Completed!')