Python Tkinter画布运行缓慢

Question

这是Life Game的代码，我认为没有问题，并且可以正常工作。

但是，当我“启动”它时，它的绘制速度越来越慢。

我想知道为什么它的速度在变慢。

# -*- coding: cp949 -*-
import Tkinter
from time import sleep

def check():
    """count alive neighbor cells and save it in list 'neighbor'
    """
    global lifegame
    global neighbor
    global indexx
    global indexy
    for y in range(0, indexy):
        for x in range(0, indexx):
            neighbor[y][x] = 0
    for y in range(0, indexy):
        for x in range (0, indexx):
            try:
                if lifegame[y-1][x-1] == 1:
                    neighbor[y][x] += 1
                if lifegame[y][x-1] == 1:
                    neighbor[y][x] += 1
                if lifegame[y+1][x-1] == 1:
                    neighbor[y][x] += 1
                if lifegame[y-1][x] == 1:
                    neighbor[y][x] += 1
                if lifegame[y+1][x] == 1:
                    neighbor[y][x] += 1
                if lifegame[y-1][x+1] == 1:
                    neighbor[y][x] += 1
                if lifegame[y][x+1] == 1:
                    neighbor[y][x] += 1
                if lifegame[y+1][x+1] == 1:
                    neighbor[y][x] += 1
            except IndexError:
                continue

def change():
    """
    check neighbor num, and change lifegame
    cell`s state 0 to 1 or 1 to  0
    """
    global lifegame
    global neighbor
    global indexx
    global indexy
    for y in range(0, indexy):
        for x in range(0, indexx):
            if lifegame[y][x] == 0:
                if neighbor[y][x] == 3:
                    lifegame[y][x] = 1
                else: continue
            elif lifegame[y][x] == 1:
                if neighbor[y][x]<2 or neighbor[y][x]>3:
                    lifegame[y][x] = 0
                else: continue

def stop():
    """
    go is  variable to stop while loop
    """
    global go
    go = False

def start():
    """
    go is  variable to stop while loop
    """
    global go
    go = True
    checkgo()

def checkgo():
    "when go is true, do while loop that will draw in canvas"
    global go
    while go:
        check()
        change()
        draw()
    print "end"

def reset():
    """kill all cells and reset"""
    global go
    global lifegame
    global neighbor
    global indexx
    global indexy
    go = False
    for y in range(0, indexy):
        for x in range(0, indexx):
            neighbor[y][x] = 0
            lifegame[y][x] = 0
    draw()

def callback(event):
    """mouse click event"""
    global go
    go = False
    print "clicked at", event.x / 10, event.y / 10
    a = event.x / 10
    b = event.y / 10
    global lifegame
    global neighbor
    if lifegame[b][a] == 0:
        lifegame[b][a] = 1
    elif lifegame[b][a] == 1:
        lifegame[b][a] = 0
    check()
    draw()

def draw():
    """draw cells on canvas"""
    global lifegame
    global indexx
    global indexy
    global tk
    for y in range(0, indexy):
        for x in range(0, indexx):
            if lifegame[y][x] == 0:
                canvas.create_polygon(10*x, 10*y, 10*x, 10+10*y, 10+10*x,
                                      10+10*y, 10+10*x, 10*y, fill='white')
            elif lifegame[y][x] == 1:
                canvas.create_polygon(10*x, 10*y, 10*x, 10+10*y, 10+10*x,
                                      10+10*y, 10+10*x, 10*y, fill='black')
    tk.update()

lifegame = []
neighbor = []
tk = Tkinter.Tk()
indexx = 10
indexy = 10
go = False
for a in range(0, indexy):
    lifegame.append([0]*indexx)
    neighbor.append([0]*indexx)
menubar = Tkinter.Menu(tk)
optionmenu = Tkinter.Menu(menubar, tearoff=0)
optionmenu.add_command(label="Start", command=start)
optionmenu.add_command(label="Stop", command=stop)
optionmenu.add_command(label="Reset", command=reset)
optionmenu.add_separator()
optionmenu.add_command(label="Exit", command=tk.quit)
tk.config(menu = menubar)
menubar.add_cascade(label="Option", menu=optionmenu)
canvas = Tkinter.Canvas(tk, width=300, height=300)
canvas.pack()
canvas.bind("<Button-1>", callback)
draw()       
tk.mainloop()

Answer 1

该代码创建多边形，但从不删除它们。

您需要明确删除它们。 使用Canvas.delete来做到这一点。

def draw():
    """draw cells on canvas"""
    global lifegame
    global indexx
    global indexy
    global tk
    canvas.delete(Tkinter.ALL)  # <---- Delete all the item created in the canvas.
    for y in range(0, indexy):
        for x in range(0, indexx):
            if lifegame[y][x] == 0:
                canvas.create_polygon(10*x, 10*y, 10*x, 10+10*y, 10+10*x,
                                      10+10*y, 10+10*x, 10*y, fill='white')
            elif lifegame[y][x] == 1:
                canvas.create_polygon(10*x, 10*y, 10*x, 10+10*y, 10+10*x,
                                      10+10*y, 10+10*x, 10*y, fill='black')
    tk.update()

而不是使用全局变量，而是将程序构造为使用类。