tkin的progressbar有问题

Question

这是我的密码

janela_barra=Toplevel()
janela_barra.title("Processando...")
janela_barra["bg"]="light grey"
janela_barra.minsize(width=400, height=80)
janela_barra.maxsize(width=400, height=80)
comprimento = janela_barra.winfo_screenwidth()
altura = janela_barra.winfo_screenheight()
x = (comprimento/2)-(400/2)
y = (altura/2)-(80/2)
janela_barra.geometry("400x80+%d+%d" % (x, y))
janela_barra.iconbitmap('icon6.ico')
pb = ttk.Progressbar(janela_barra, orient=HORIZONTAL, length=200, mode='determinate')
pb.grid(column=0,row=0)
pb["value"]=0 
pb["maximum"]=100

然后在a中有一个：

^{pr2}$

其中tamanho是for的迭代次数（现在是420），但问题是，它只打开一个窗口然后关闭，我看不到progressbar实际起作用，不管我增加了多少tamanho

Answer 1

只需在循环中添加sleep（来自模块time）就可以看到进程。下面是一个例子：

from tkinter import Tk, Button, Toplevel
from tkinter import ttk
from time import sleep

root = Tk()

def fct_run_for():
    top=Toplevel(root)
    top.title("Progression")
    pb = ttk.Progressbar(top, orient="horizontal", length=200, mode='determinate')
    pb.grid(column=0,row=0)
    pb["value"]=0 
    pb["maximum"]=100
    for i in range(100):
        pb["value"] += 1
        pb.update()
        sleep(0.1)

Button(root, text="Run", command=fct_run_for).pack()
root.mainloop()