Tkinter单选按钮在已选择时执行命令

一个简单的解决方案是使用变量来跟踪 Radiobutton 最后按下(我称之为 prev_btn 这里)。

这个 command 函数可以检查此值,并且只有当它与上次调用函数时相比发生更改时才能执行。之后,该函数存储更新的按钮值。

import tkinter as tk


def on_choice():
    # set prev_btn  as a global so this function can modify its value
    global prev_btn
    # only trigger the useful stuff if the button is different from last time
    if radiobutton_variable.get() != prev_btn:  # if button changed...
        print('Function executed')
        # store the value of the most recently pressed button
        prev_btn = radiobutton_variable.get()


root = tk.Tk()
root.geometry('300x150')

radiobutton_variable = tk.StringVar()
radiobutton_variable.set(1)

# define a variable to store the current button state
# (you could also set this to '1', but doing it this way means you won't have to
#  update the default value in two places in case you decide to change it above!)
prev_btn = radiobutton_variable.get()

button_1 = tk.Radiobutton(root, text='Button 1', variable=radiobutton_variable, value=1, command=on_choice)
button_2 = tk.Radiobutton(root, text='Button 2', variable=radiobutton_variable, value=2, command=on_choice)

button_1.pack()
button_2.pack()

root.mainloop()