在 Tkinter Canvas 中 3 秒后更改图片

Question

在 Tkinter 画布中，我想显示 pic1.gif 并在 3 秒后将图片更改为 pic2.gif。当我运行下面的程序时，它会立即显示 pic2.gif。

from tkinter import *
from time import sleep


canvas_width = 300
canvas_height =300

master = Tk()

canvas = Canvas(master, 
           width=canvas_width, 
           height=canvas_height)
canvas.pack()

img = PhotoImage(file="pic1.gif")
canvas.create_image(20,20, anchor=NW, image=img)
sleep(3)
canvas.delete("all")
img = PhotoImage(file="pic2.gif")
canvas.create_image(20,20, anchor=NW, image=img)
mainloop()

非常感谢！

Answer 1

你不能在 tkinter 中使用time.sleep，你必须使用主循环，你可以通过after 方法访问它。

from tkinter import *

canvas_width = 300
canvas_height =300

master = Tk()

canvas = Canvas(master, 
           width=canvas_width, 
           height=canvas_height)
canvas.pack()

img = PhotoImage(file="pic1.gif")
canvas.create_image(20,20, anchor=NW, image=img)

def change_img():
    canvas.delete("all")
    canvas.img = PhotoImage(file="pic2.gif")
    canvas.create_image(20,20, anchor=NW, image=canvas.img)

master.after(3000, change_img) # run the change_img function in 3,000 milliseconds

mainloop()