有没有一种方法可以使用Python在终端上打印旋转的光标?
Answers:
假设您的终端处理\ b,则类似这样
import sys
import time
def spinning_cursor():
while True:
for cursor in '|/-\\':
yield cursor
spinner = spinning_cursor()
for _ in range(50):
sys.stdout.write(next(spinner))
sys.stdout.flush()
time.sleep(0.1)
sys.stdout.write('\b')
易于使用的API(将在单独的线程中运行微调器):
import sys
import time
import threading
class Spinner:
busy = False
delay = 0.1
@staticmethod
def spinning_cursor():
while 1:
for cursor in '|/-\\': yield cursor
def __init__(self, delay=None):
self.spinner_generator = self.spinning_cursor()
if delay and float(delay): self.delay = delay
def spinner_task(self):
while self.busy:
sys.stdout.write(next(self.spinner_generator))
sys.stdout.flush()
time.sleep(self.delay)
sys.stdout.write('\b')
sys.stdout.flush()
def __enter__(self):
self.busy = True
threading.Thread(target=self.spinner_task).start()
def __exit__(self, exception, value, tb):
self.busy = False
time.sleep(self.delay)
if exception is not None:
return False
现在with
在代码中任意位置的块中使用它:
with Spinner():
# ... some long-running operations
# time.sleep(3)
float(delay)
将提高如果没有浮动,应该是isinstance(delay, Number)
,与Number
从numbers
。
一个很好的pythonic方法是使用itertools.cycle:
import itertools, sys
spinner = itertools.cycle(['-', '/', '|', '\\'])
while True:
sys.stdout.write(next(spinner)) # write the next character
sys.stdout.flush() # flush stdout buffer (actual character display)
sys.stdout.write('\b') # erase the last written char
另外,您可能希望在长函数调用期间使用线程来显示微调框,例如http://www.interclasse.com/scripts/spin.php
next(spinner)
代替spinner.next()
spinner = itertools.cycle('-/|\\')
。
@Victor Moyseenko的改进版本,因为原始版本几乎没有问题
import sys
import threading
import itertools
import time
class Spinner:
def __init__(self, message, delay=0.1):
self.spinner = itertools.cycle(['-', '/', '|', '\\'])
self.delay = delay
self.busy = False
self.spinner_visible = False
sys.stdout.write(message)
def write_next(self):
with self._screen_lock:
if not self.spinner_visible:
sys.stdout.write(next(self.spinner))
self.spinner_visible = True
sys.stdout.flush()
def remove_spinner(self, cleanup=False):
with self._screen_lock:
if self.spinner_visible:
sys.stdout.write('\b')
self.spinner_visible = False
if cleanup:
sys.stdout.write(' ') # overwrite spinner with blank
sys.stdout.write('\r') # move to next line
sys.stdout.flush()
def spinner_task(self):
while self.busy:
self.write_next()
time.sleep(self.delay)
self.remove_spinner()
def __enter__(self):
if sys.stdout.isatty():
self._screen_lock = threading.Lock()
self.busy = True
self.thread = threading.Thread(target=self.spinner_task)
self.thread.start()
def __exit__(self, exception, value, tb):
if sys.stdout.isatty():
self.busy = False
self.remove_spinner(cleanup=True)
else:
sys.stdout.write('\r')
上面的Spinner类的使用示例:
with Spinner("just waiting a bit.. "):
time.sleep(3)
为了完整性,我想添加一个很棒的包halo。它提供了许多预设微调器和更高级别的自定义选项。
from halo import Halo
spinner = Halo(text='Loading', spinner='dots')
spinner.start()
# Run time consuming work here
# You can also change properties for spinner as and when you want
spinner.stop()
或者,您可以将halo与Python的with语句一起使用:
from halo import Halo
with Halo(text='Loading', spinner='dots'):
# Run time consuming work here
最后,您可以使用halo作为装饰器:
from halo import Halo
@Halo(text='Loading', spinner='dots')
def long_running_function():
# Run time consuming work here
pass
long_running_function()
当然可以。这只是一个打印退格字符(的问题\b
在四个字符,否则会给“光标”看起来它旋转之间)( ,-
,\
,)。|
/
对于更高级的控制台操作,在Unix上可以使用curses python模块,在Windows上可以使用WConio,它提供了curses库的等效功能。
抓住很棒的progressbar
模块-http://code.google.com/p/python-progressbar/
使用RotatingMarker
。
我在GitHub上找到了py-spin包。它具有许多不错的旋转样式。以下是关于如何使用一些样本,Spin1
是\-/
风格:
from __future__ import print_function
import time
from pyspin.spin import make_spin, Spin1
# Choose a spin style and the words when showing the spin.
@make_spin(Spin1, "Downloading...")
def download_video():
time.sleep(10)
if __name__ == '__main__':
print("I'm going to download a video, and it'll cost much time.")
download_video()
print("Done!")
time.sleep(0.1)
也可以手动控制旋转:
from __future__ import print_function
import sys
import time
from pyspin.spin import Spin1, Spinner
# Choose a spin style.
spin = Spinner(Spin1)
# Spin it now.
for i in range(50):
print(u"\r{0}".format(spin.next()), end="")
sys.stdout.flush()
time.sleep(0.1)
以下gif中的其他样式。
#!/usr/bin/env python
import sys
chars = '|/-\\'
for i in xrange(1,1000):
for c in chars:
sys.stdout.write(c)
sys.stdout.write('\b')
sys.stdout.flush()
请注意: 根据我的经验,这并不适用于所有终端。在Unix / Linux下,更健壮的方法是使用curses模块,因为它更为复杂,而该模块在Windows下不起作用。您可能希望通过后台正在进行的实际处理来减慢其速度。
我提出使用装饰器的解决方案
from itertools import cycle
import functools
import threading
import time
def spinner(message, spinner_symbols: list = None):
spinner_symbols = spinner_symbols or list("|/-\\")
spinner_symbols = cycle(spinner_symbols)
global spinner_event
spinner_event = True
def start():
global spinner_event
while spinner_event:
symbol = next(spinner_symbols)
print("\r{message} {symbol}".format(message=message, symbol=symbol), end="")
time.sleep(0.3)
def stop():
global spinner_event
spinner_event = False
print("\r", end="")
def external(fct):
@functools.wraps(fct)
def wrapper(*args):
spinner_thread = threading.Thread(target=start, daemon=True)
spinner_thread.start()
result = fct(*args)
stop()
spinner_thread.join()
return result
return wrapper
return external
使用简单
@spinner("Downloading")
def f():
time.sleep(10)
我建立了一个通用的Singleton,由整个应用程序共享
from itertools import cycle
import threading
import time
class Spinner:
__default_spinner_symbols_list = ['|-----|', '|#----|', '|-#---|', '|--#--|', '|---#-|', '|----#|']
def __init__(self, spinner_symbols_list: [str] = None):
spinner_symbols_list = spinner_symbols_list if spinner_symbols_list else Spinner.__default_spinner_symbols_list
self.__screen_lock = threading.Event()
self.__spinner = cycle(spinner_symbols_list)
self.__stop_event = False
self.__thread = None
def get_spin(self):
return self.__spinner
def start(self, spinner_message: str):
self.__stop_event = False
time.sleep(0.3)
def run_spinner(message):
while not self.__stop_event:
print("\r{message} {spinner}".format(message=message, spinner=next(self.__spinner)), end="")
time.sleep(0.3)
self.__screen_lock.set()
self.__thread = threading.Thread(target=run_spinner, args=(spinner_message,), daemon=True)
self.__thread.start()
def stop(self):
self.__stop_event = True
if self.__screen_lock.is_set():
self.__screen_lock.wait()
self.__screen_lock.clear()
print("\r", end="")
print("\r", end="")
if __name__ == '__main__':
import time
# Testing
spinner = Spinner()
spinner.start("Downloading")
# Make actions
time.sleep(5) # Simulate a process
#
spinner.stop()
您可以写'\r\033[K'
以清除当前行。以下是从@nos修改的示例。
import sys
import time
def spinning_cursor():
while True:
for cursor in '|/-\\':
yield cursor
spinner = spinning_cursor()
for _ in range(1, 10):
content = f'\r{next(spinner)} Downloading...'
print(content, end="")
time.sleep(0.1)
print('\r\033[K', end="")
对于任何对nodejs感兴趣的人,我也写一个nodejs示例。
function* makeSpinner(start = 0, end = 100, step = 1) {
let iterationCount = 0;
while (true) {
for (const char of '|/-\\') {
yield char;
}
}
return iterationCount;
}
async function sleep(seconds) {
return new Promise((resolve) => {
setTimeout(resolve, seconds * 1000);
});
}
(async () => {
const spinner = makeSpinner();
for (let i = 0; i < 10; i++) {
content = `\r${spinner.next().value} Downloading...`;
process.stdout.write(content);
await sleep(0.1);
process.stdout.write('\r\033[K');
}
})();
我大约一个星期前才刚开始使用python,并发现了此信息。我将在这里找到的内容与在其他地方了解到的有关线程和队列的知识相结合,以提供更好的实现。在我的解决方案中,写入屏幕是由检查内容队列的线程处理的。如果该队列中有内容,则游标旋转线程知道会停止。在另一方面,游标旋转线程将队列用作锁,因此打印线程知道在完成完整的旋转代码后才进行打印。这样可以防止出现争用情况,并防止人们使用过多的代码来保持控制台的清洁。
见下文:
import threading, queue, itertools, sys, time # all required for my version of spinner
import datetime #not required for spinning cursor solution, only my example
console_queue = queue.Queue() # this queue should be initialized before functions
screenlock = queue.Queue() # this queue too...
def main():
threading.Thread(target=spinner).start()
threading.Thread(target=consoleprint).start()
while True:
# instead of invoking print or stdout.write, we just add items to the console_queue
# The next three lines are an example of my code in practice.
time.sleep(.5) # wait half a second
currenttime = "[" + datetime.datetime.now().strftime("%d/%m/%Y %H:%M:%S") + "] "
console_queue.put(currenttime) # The most important part. Substitute your print and stdout functions with this.
def spinner(console_queue = console_queue, screenlock = screenlock):
spinnerlist = itertools.cycle(['|', '/', '-', '\\'])
while True:
if console_queue.empty():
screenlock.put("locked")
sys.stdout.write(next(spinnerlist))
sys.stdout.flush()
sys.stdout.write('\b')
sys.stdout.flush()
screenlock.get()
time.sleep(.1)
def consoleprint(console_queue = console_queue, screenlock = screenlock):
while True:
if not console_queue.empty():
while screenlock.empty() == False:
time.sleep(.1)
sys.stdout.flush()
print(console_queue.get())
sys.stdout.flush()
if __name__ == "__main__":
main()
说完我说的所有内容并写完所有内容后,我只做了python一周的工作。如果有更清洁的方法可以这样做,或者我错过了一些我想学习的最佳实践。谢谢。
import requests
import time
import sys
weathercity = input("What city are you in? ")
weather = requests.get('http://api.openweathermap.org/data/2.5/weather?q='+weathercity+'&appid=886705b4c1182eb1c69f28eb8c520e20')
url = ('http://api.openweathermap.org/data/2.5/weather?q='+weathercity+'&appid=886705b4c1182eb1c69f28eb8c520e20')
def spinning_cursor():
while True:
for cursor in '|/-\\':
yield cursor
data = weather.json()
temp = data['main']['temp']
description = data['weather'][0]['description']
weatherprint ="In {}, it is currently {}°C with {}."
spinner = spinning_cursor()
for _ in range(25):
sys.stdout.write(next(spinner))
sys.stdout.flush()
time.sleep(0.1)
sys.stdout.write('\b')
convert = int(temp - 273.15)
print(weatherprint.format(weathercity, convert, description))
spinner = itertools.cycle(['-', '/', '|', '\\'])
而不是创建一个生成器功能(更简洁,更重用)如图所示这里