它在我的程序中工作得很好。此外，我们需要添加一个计数器来指示循环时间。这个计数器作为方法update的参数。 例如:读取测试文件的所有行，并对它们进行处理。假设函数dosth()与变量i无关。

lines = open(sys.argv[1]).readlines()
i = 0
widgets=[Percentage(), Bar()]
pbar = ProgressBar(widgets=widgets,maxval=len(lines)).start()
pbar.start()
for line in lines:<pre>
    dosth();
    i += 1
    pbar.update(i)</pre>
pbar.finish()

变量i通过方法update控制pbar的状态

您应该将进度条链接到手头的任务(以便它度量进度:D)。例如，如果您正在对一个文件进行ftp传输，您可以告诉ftplib获取一个特定大小的缓冲区，比如128K，然后您将128K所代表的文件大小的百分比添加到进度条中。如果您正在使用CLI，并且进度表有20个字符长，那么当文件传输了1/20时，您将添加一个字符。

使用进度库!

pip install progress

下面是我编写的一个自定义子类，用于将ETA/流逝时间格式化为更好读的格式:

import datetime
from progress.bar import IncrementalBar


class ProgressBar(IncrementalBar):
    '''
    My custom progress bar that:
       - Show %, count, elapsed, eta
       - Time is shown in H:M:S format
    '''

    message = 'Progress'
    suffix  = '%(percent).1f%% (%(index)d/%(max)d) -- %(elapsed_min)s (eta: %(eta_min)s)'

    def formatTime(self, seconds):
        return str(datetime.timedelta(seconds=seconds))

    @property
    def elapsed_min(self):
        return self.formatTime(self.elapsed)

    @property
    def eta_min(self):
        return self.formatTime(self.eta)

if __name__=='__main__':
    counter = 120
    bar     = ProgressBar('Processing', max=counter)

    for i in range(counter):
        bar.next()
        time.sleep(1)

    bar.finish()

#doesnt affect actual execution
#based on events and consumption in background
#may be that actual process completes a bit earlier than progress shows 99%
#make an instance with number of elements in a loop
#in each iteration call the method current_progress

import time
from math import ceil
import os
import sys
from threading import Thread
class progress_bar(object):
 def __init__(self,total_elements,length_bar=25):
  self.length_bar=length_bar
  self.total_elements=total_elements
  self.singleweight=(float(1)/float(total_elements))*100
  self.done=0
  self.qt=[0]
  self.call_count=0
  t=Thread(target=self.display_progress)
  t.start()
 def current_progress(self):
  self.done+=1
  self.qt=[self.done]+self.qt
 def display_progress(self):
  while True:
   try:
    done=self.qt.pop()
   except:
    continue
   else:
    self.call_count+=1
    self.progress=self.singleweight*done
    fill=ceil(self.progress)
    bar=int((fill*self.length_bar)/100)*"|"
    bar="["+bar+str(fill)+"%"
    barp=bar
    for i in range(0,self.length_bar+3-(len(bar))):
     barp=barp+"_"
    barp=barp+"]"
    if self.progress <= 100:
     os.system("clear")
     print("Progress:",barp, sep=' ', end='\n', file=sys.stdout, flush=True)
    if self.call_count == self.total_elements:
     break
  else:
   pass

在这里寻找等效的解决方案后，我只是为我的需求做了一个简单的进度类。我想我应该把它贴出来。

from __future__ import print_function
import sys
import re


class ProgressBar(object):
    DEFAULT = 'Progress: %(bar)s %(percent)3d%%'
    FULL = '%(bar)s %(current)d/%(total)d (%(percent)3d%%) %(remaining)d to go'

    def __init__(self, total, width=40, fmt=DEFAULT, symbol='=',
                 output=sys.stderr):
        assert len(symbol) == 1

        self.total = total
        self.width = width
        self.symbol = symbol
        self.output = output
        self.fmt = re.sub(r'(?P<name>%\(.+?\))d',
            r'\g<name>%dd' % len(str(total)), fmt)

        self.current = 0

    def __call__(self):
        percent = self.current / float(self.total)
        size = int(self.width * percent)
        remaining = self.total - self.current
        bar = '[' + self.symbol * size + ' ' * (self.width - size) + ']'

        args = {
            'total': self.total,
            'bar': bar,
            'current': self.current,
            'percent': percent * 100,
            'remaining': remaining
        }
        print('\r' + self.fmt % args, file=self.output, end='')

    def done(self):
        self.current = self.total
        self()
        print('', file=self.output)

例子:

from time import sleep

progress = ProgressBar(80, fmt=ProgressBar.FULL)

for x in xrange(progress.total):
    progress.current += 1
    progress()
    sleep(0.1)
progress.done()

将打印以下内容:

[========] 17/80 (21%) 63

下面的代码是一个相当通用的解决方案，也有一个时间消耗和剩余时间估计。你可以使用任何可迭代对象。进度条的大小固定为25个字符，但可以使用完整、半块和四分之一块字符以1%的速度显示更新。输出如下所示:

 18% |████▌                    | \ [0:00:01, 0:00:06]

代码示例:

import sys, time
from numpy import linspace

def ProgressBar(iterObj):
  def SecToStr(sec):
    m, s = divmod(sec, 60)
    h, m = divmod(m, 60)
    return u'%d:%02d:%02d'%(h, m, s)
  L = len(iterObj)
  steps = {int(x):y for x,y in zip(linspace(0, L, min(100,L), endpoint=False),
                                   linspace(0, 100, min(100,L), endpoint=False))}
  qSteps = ['', u'\u258E', u'\u258C', u'\u258A'] # quarter and half block chars
  startT = time.time()
  timeStr = '   [0:00:00, -:--:--]'
  activity = [' -',' \\',' |',' /']
  for nn,item in enumerate(iterObj):
    if nn in steps:
      done = u'\u2588'*int(steps[nn]/4.0)+qSteps[int(steps[nn]%4)]
      todo = ' '*(25-len(done))
      barStr = u'%4d%% |%s%s|'%(steps[nn], done, todo)
    if nn>0:
      endT = time.time()
      timeStr = ' [%s, %s]'%(SecToStr(endT-startT),
                             SecToStr((endT-startT)*(L/float(nn)-1)))
    sys.stdout.write('\r'+barStr+activity[nn%4]+timeStr); sys.stdout.flush()
    yield item
  barStr = u'%4d%% |%s|'%(100, u'\u2588'*25)
  timeStr = '   [%s, 0:00:00]\n'%(SecToStr(time.time()-startT))
  sys.stdout.write('\r'+barStr+timeStr); sys.stdout.flush()

# Example
s = ''
for c in ProgressBar(list('Disassemble and reassemble this string')):
  time.sleep(0.2)
  s += c
print(s)

欢迎提出改进建议或其他意见。干杯!