Tkinter create_rectangle性能

Question

我使用create_rectangle在无限循环中绘制和更新画布上的WxH网格。我注意到几分钟后刷新速度大大减慢。经过阅读，我意识到create_rectangle创建了一个对象，我认为这是导致性能问题的原因。有没有办法在不创建新矩形的情况下改变矩形对象的颜色？如果没有，是否需要在重新绘制网格之前删除网格中的所有矩形？我认为性能问题是由于创造了成千上万的长方形，永远不会消失。

# Conway's Game of Life
# Algorithm and code taken from Al Sweigart's "Automate the Boring Stuff with Python"

import random, time, copy
from tkinter import *
# import gc

ASCII = False

WIDTH = 50
HEIGHT = 50
side = 15 # Length of a cell's side

def genesis():    
    for x in range(WIDTH):
        for y in range(HEIGHT):
            if random.randint(0, 1) == 1:
                nextCells[x][y] = True
    draw_world(nextCells)
            
def draw_world(grid):
    for x in range(WIDTH):
        for y in range(HEIGHT):
            if grid[x][y]:
                if ASCII:
                    print('#', end='')
                else:
                    canvas.create_rectangle(x*side, y*side, x*side+side, y*side+side, fill='black')
            else:
                if ASCII:
                    print(' ', end='') # Print the # or space.
                else:                
                    canvas.create_rectangle(x*side, y*side, x*side+side, y*side+side, fill='white', outline="white") # no grid lines
        if ASCII: 
            print() # Print a newline at the end of the row.
                

def live():
    # root.update()
    currentCells = copy.deepcopy(nextCells)

    # Calculate the next step's cells based on current step's cells:
    for x in range(WIDTH):
        for y in range(HEIGHT):
            # Get neighboring coordinates:
            # `% WIDTH` ensures leftCoord is always between 0 and WIDTH - 1
            leftCoord  = (x - 1) % WIDTH
            rightCoord = (x + 1) % WIDTH
            aboveCoord = (y - 1) % HEIGHT
            belowCoord = (y + 1) % HEIGHT

            # Count number of living neighbors:
            numNeighbors = 0
            if currentCells[leftCoord][aboveCoord]:
                numNeighbors += 1 # Top-left neighbor is alive.
            if currentCells[x][aboveCoord]:
                numNeighbors += 1 # Top neighbor is alive.
            if currentCells[rightCoord][aboveCoord]:
                numNeighbors += 1 # Top-right neighbor is alive.
            if currentCells[leftCoord][y]:
                numNeighbors += 1 # Left neighbor is alive.
            if currentCells[rightCoord][y]:
                numNeighbors += 1 # Right neighbor is alive.
            if currentCells[leftCoord][belowCoord]:
                numNeighbors += 1 # Bottom-left neighbor is alive.
            if currentCells[x][belowCoord]:
                numNeighbors += 1 # Bottom neighbor is alive.
            if currentCells[rightCoord][belowCoord]:
                numNeighbors += 1 # Bottom-right neighbor is alive.

            # Set cell based on Conway's Game of Life rules:
            if currentCells[x][y] and (numNeighbors == 2 or numNeighbors == 3):
                # Living cells with 2 or 3 neighbors stay alive:
                nextCells[x][y] = True
            elif not currentCells[x][y] and numNeighbors == 3:
                # Dead cells with 3 neighbors become alive:
                nextCells[x][y] = True
            else:
                # Everything else dies or stays dead:
                nextCells[x][y] = False
    draw_world(nextCells)
    # del currentCells
    if ASCII:
        time.sleep(1) # 1-second pause between frames
    # gc.collect()
    root.after(1000, live)
                
    
root = Tk()
root.title("Conway Game of Life")

frame = Frame(root, width=WIDTH*side, height=HEIGHT*side)
frame.pack(expand=True, fill=BOTH)

canvas = Canvas(frame, bg='white', width=WIDTH*side, height=HEIGHT*side)
canvas.pack(side=LEFT, expand=True, fill=BOTH)
nextCells = [[False] * WIDTH for i in range(HEIGHT)]
    
genesis()
live()

root.mainloop()

Answer 1

是否有一种方法可以改变矩形对象的颜色而不创建新的矩形？

是。该方法称为itemconfigure。您需要矩形id或与矩形关联的标记的名称。

canvas = tk.Canvas(...)
rectangle = canvas.create_rectangle(...)
...
canvas.itemconfigure(rectangle, fill="red")