python curses中的进度栏

Question

I have created a progress bar which updates itself after getting a percentage from another function but I'm having issues getting it to trail like this ############. Instead, it just move the '#' to the right until 100% is reached. Below is my code. The reason why it's this way is because I need the percentage to come externally so that the code can be reusable. please help me.

import curses
import time

curses.initscr()

def percentage():
    loading = 0
    while loading < 100:
        loading += 1
        time.sleep(0.03)
        update_progress(loading)


def update_progress(progress):
    win = curses.newwin(3, 32, 3, 30)
    win.border(0)
    rangex = (30 / float(100)) * progress
    pos = int(rangex)
    display = '#'
    if pos != 0:
        win.addstr(1, pos, "{}".format(display))
        win.refresh()

percentage()

Answer 1

The problem is that you call newwin() every time, discarding the old win and replacing it with a new one in the same place. That new window only gets one character added to it, with the background being blank, so you see an advancing cursor instead of a bar.

One possible solution:

import curses
import time

curses.initscr()

def percentage():
    win = curses.newwin(3, 32, 3, 30)
    win.border(0)
    loading = 0
    while loading < 100:
        loading += 1
        time.sleep(0.03)
        update_progress(win, loading)

def update_progress(win, progress):
    rangex = (30 / float(100)) * progress
    pos = int(rangex)
    display = '#'
    if pos != 0:
        win.addstr(1, pos, "{}".format(display))
        win.refresh()

percentage()

curses.endwin()

(Note the addition of a call to endwin() to restore the terminal to its normal mode.)

As far as leaving it onscreen after the program finishes, that's kind of outside the scope of curses. You can't really depend on any interaction between curses and stdio, sorry.

Answer 2

you can just switch the pos to multiply the display # :

if pos != 0:
    win.addstr(1, 1, "{}".format(display*pos))
    win.refresh()