在python中注册屏幕更改？

Question

因此，使用tkinter，我编写了一个简单的程序，每秒钟将画布上所有形状的颜色更改为随机颜色，我正在寻找的是一种方法，可以注册每个屏幕更改，并在一个单独的文件中记录屏幕更改之间的时间。如果可能的话，我还需要在没有太多外部库的情况下这样做。

到目前为止我的代码是：

#!/usr/bin/python -W ignore::DeprecationWarning
import Tkinter
import tkMessageBox
import time
import random


colors = ['DarkOrchid1','chocolate3','gold2','khaki2','chartreuse2','deep pink','white','grey','orange']
top = Tkinter.Tk()
global b
b=0
C = Tkinter.Canvas(top, bg="blue", height=600, width=800)
bcg1=C.create_rectangle(0,0,800,100,fill=random.choice(colors))
bcg2=C.create_rectangle(0,100,800,200,fill=random.choice(colors))
bcg3=C.create_rectangle(0,200,800,300,fill=random.choice(colors))
bcg4=C.create_rectangle(0,300,800,400,fill=random.choice(colors))
bcg5=C.create_rectangle(0,400,800,500,fill=random.choice(colors))
bcg6=C.create_rectangle(0,500,800,600,fill=random.choice(colors))
bcgs=[bcg1,bcg2,bcg3,bcg4,bcg5,bcg6]
coord = 10, 50, 240, 210
rect1=C.create_rectangle(0,0,100,100,fill="green")
rect2=C.create_rectangle(700,500,800,600,fill="green")
rect3=C.create_rectangle(0,500,100,600,fill="green")
rect4=C.create_rectangle(700,0,800,100,fill="green")
def color():
    global b
    global bcgs
    global color
    if b==0:
        C.itemconfig(rect1,fill='green')
        C.itemconfig(rect2,fill='green')
        C.itemconfig(rect3,fill='green')
        C.itemconfig(rect4,fill='green')
        b=1
        count=0
        for i in range(len(bcgs)):
            C.itemconfig(bcgs[i],fill=random.choice(colors))

    elif b==1:
        C.itemconfig(rect1,fill='red')
        C.itemconfig(rect2,fill='red')
        C.itemconfig(rect3,fill='red')
        C.itemconfig(rect4,fill='red')
        b=0
        for i in range(len(bcgs)):
            C.itemconfig(bcgs[i],fill=random.choice(colors))


    top.after(2000, color)

C.pack()
color()
top.mainloop()

Answer 1

除非你使用实时操作系统，否则你永远不会得到完美的时机。你可以指望几毫秒就好了。要查看多少，您可以计算time.time()中的差异。为了获得最佳的精度，将after调用移到函数中的第一件事。

再加上其他一些改进：

#!/usr/bin/python -W ignore::DeprecationWarning
import Tkinter
import time
import random
from itertools import cycle

colors = ['DarkOrchid1','chocolate3','gold2','khaki2','chartreuse2','deep pink','white','grey','orange']
rect_colors = cycle(['green', 'red'])

top = Tkinter.Tk()
C = Tkinter.Canvas(top, bg="blue", height=600, width=800)
bcg1=C.create_rectangle(0,0,800,100,fill=random.choice(colors))
bcg2=C.create_rectangle(0,100,800,200,fill=random.choice(colors))
bcg3=C.create_rectangle(0,200,800,300,fill=random.choice(colors))
bcg4=C.create_rectangle(0,300,800,400,fill=random.choice(colors))
bcg5=C.create_rectangle(0,400,800,500,fill=random.choice(colors))
bcg6=C.create_rectangle(0,500,800,600,fill=random.choice(colors))
bcgs=[bcg1,bcg2,bcg3,bcg4,bcg5,bcg6]
coord = 10, 50, 240, 210
rect1=C.create_rectangle(0,0,100,100,fill="green")
rect2=C.create_rectangle(700,500,800,600,fill="green")
rect3=C.create_rectangle(0,500,100,600,fill="green")
rect4=C.create_rectangle(700,0,800,100,fill="green")
rects = [rect1,rect2,rect3,rect4]

last_time = time.time()
def color():
    top.after(2000, color)
    global last_time

    rect_color = next(rect_colors)
    for item in rects:
        C.itemconfig(item, fill=rect_color)
    for item in bcgs:
        C.itemconfig(item, fill=random.choice(colors))

    print("{} seconds since the last run".format(time.time() - last_time))
    last_time = time.time()

C.pack()
color()
top.mainloop()