Tkinter按钮command传参致函数提前执行的解决办法

方法1：使用lambda表达式 #

lambda可以创建匿名函数，把带参数的play函数调用包裹起来，只有按钮被点击时才会执行这个匿名函数，进而触发play逻辑。

修改原代码中设置play_button的command行：

play_button.config(command=lambda: play(title, play_button, exit_button))

完整主文件代码：

import tkinter
from play_function import *

window = tkinter.Tk()
screen_width = window.winfo_screenwidth()
screen_height = window.winfo_screenheight()
window.config(width=screen_width)
window.config(height=screen_height)
window.config(background="black")
title = tkinter.Label(window, text="Scrabble", background="black", foreground="green", font=("Comic Sans MS", 200))
title.pack()
play_button = tkinter.Button(window, text="PLAY", background="blue", foreground="black", font=("Comic Sans MS", 80))
exit_button = tkinter.Button(window, text="EXIT", background="red", foreground="black", font=("Comic Sans MS", 77), command=window.destroy)
# 用lambda包裹函数调用，避免启动时执行
play_button.config(command=lambda: play(title, play_button, exit_button))
space = tkinter.Label(foreground="black", background="black", height=2, width=50)

play_button.pack()
space.pack()
exit_button.pack()

window.mainloop()

方法2：使用functools.partial #

functools.partial能预先绑定函数参数，生成新的可调用对象，直接赋值给command即可实现点击触发。

先导入functools模块，再修改command设置：

import functools
play_button.config(command=functools.partial(play, title, play_button, exit_button))

完整主文件代码：

import tkinter
import functools
from play_function import *

window = tkinter.Tk()
screen_width = window.winfo_screenwidth()
screen_height = window.winfo_screenheight()
window.config(width=screen_width)
window.config(height=screen_height)
window.config(background="black")
title = tkinter.Label(window, text="Scrabble", background="black", foreground="green", font=("Comic Sans MS", 200))
title.pack()
play_button = tkinter.Button(window, text="PLAY", background="blue", foreground="black", font=("Comic Sans MS", 80))
exit_button = tkinter.Button(window, text="EXIT", background="red", foreground="black", font=("Comic Sans MS", 77), command=window.destroy)
# 用partial绑定参数，生成可调用对象
play_button.config(command=functools.partial(play, title, play_button, exit_button))
space = tkinter.Label(foreground="black", background="black", height=2, width=50)

play_button.pack()
space.pack()
exit_button.pack()

window.mainloop()

问题原因说明 #

你原本的写法play_button.config(command=play(title, play_button, exit_button))会在程序启动时立即执行play函数——因为这是直接调用函数并将返回值（此处为None）赋值给command。而Tkinter按钮的command需要的是一个可调用对象（即不带括号的函数本身），只有点击时才会触发执行。

上述两种方法都是将带参数的函数调用包装成可调用对象，彻底避免了启动时的提前执行。

内容的提问来源于stack exchange，提问作者Game Master 2.0