Python Tkinter 在执行某些任务时显示加载动画

Question

我从 https://www.daniweb.com/programming/software-development/threads/396918/how-to-use-animated-gifs-with-tkinter 找到了这个有用的 Tkinter 动画代码，由“vegaseat”提供。

我采用了类似的设计来向项目显示 gif 动画。我希望将此实现为脚本某些区域的功能，例如导入模块等。我尝试了一些方法，但是当我将其作为函数调用时，它首先运行动画，然后导入模块（正如我们所期望的那样）。

我想我正在探索让它同时工作的方法......当脚本正在导入模块（或运行我希望显示动画的另一个进程）时，动画将显示，然后消失，直到下一个电话。建议将不胜感激。

非常感谢。

# mimic an animated GIF displaying a series of GIFs
# an animated GIF was used to create the series of GIFs 
# with a common GIF animator utility

import time
from Tkinter import *
root = Tk()
imagelist = ["dog001.gif","dog002.gif","dog003.gif",
             "dog004.gif","dog005.gif","dog006.gif","dog007.gif"]
# extract width and height info
photo = PhotoImage(file=imagelist[0])
width = photo.width()
height = photo.height()
canvas = Canvas(width=width, height=height)
canvas.pack()
# create a list of image objects
giflist = []
for imagefile in imagelist:
    photo = PhotoImage(file=imagefile)
    giflist.append(photo)
# loop through the gif image objects for a while
for k in range(0, 1000):
    for gif in giflist:
        canvas.delete(ALL)
        canvas.create_image(width/2.0, height/2.0, image=gif)
        canvas.update()
        time.sleep(0.1)
root.mainloop()

编辑：根据一些有用的建议，我正在尝试实现下面的代码。目标是在应用程序导入“IMPORTS”函数中的模块时开始动画，然后在导入完成后将其销毁。

# Import modules
from Tkinter import *
from PIL import ImageTk
from PIL import Image
import os,time
from os.path import dirname
from os.path import join

def IMPORTS():
    import tkMessageBox
    from ttk import Combobox
    import csv,datetime
    import xlrd,xlwt
    import getpass
    import traceback
    import arcpy
    from arcpy import AddMessage
    import win32com.client


inGif = #root image (.gif)
FramesFolder = #Folder containing frames of the root image

W=Toplevel() 
W.wm_overrideredirect(True) # I wish to only display the widget spinning without the window frame

imagelist = [os.path.join(FramesFolder,s) for s in os.listdir(FramesFolder) if not s.endswith('db')]
# extract width and height info
photo = PhotoImage(file=imagelist[0])
width = photo.width()
height = photo.height()
canvas = Canvas(W,width=width, height=height)
canvas.pack()
# create a list of image objects
giflist = []
for imagefile in imagelist:
    photo = PhotoImage(file=imagefile)
    giflist.append(photo)

timer_id = None

def start_loading(n=0):
    global timer_id
    gif = giflist[n%len(giflist)]
    canvas.create_image(gif.width()//2, gif.height()//2, image=gif)
    timer_id = W.after(100, start_loading, n+1) # call this function every 100ms

def stop_loading():
    if timer_id:
        W.after_cancel(timer_id)
        canvas.delete(ALL)

start_loading()
IMPORTS()
stop_loading()
# The spinning widget should be completely destroyed before moving on...

它正在返回

"NameError: name 'tkMessageBox' is not defined"

Answer 1

您可以使用Tk.after() 和Tk.after_cancel() 来启动和停止动画：

timer_id = None

def start_loading(n=0):
    global timer_id
    gif = giflist[n%len(giflist)]
    canvas.create_image(gif.width()//2, gif.height()//2, image=gif)
    timer_id = root.after(100, start_loading, n+1) # call this function every 100ms

def stop_loading():
    if timer_id:
        root.after_cancel(timer_id)
        canvas.delete(ALL)

那么，你可以在长进程前调用start_loading()，在长进程后调用stop_loading()：

start_loading()
long_process() # your long process
stop_loading()