如何更新循环中创建的按钮和标签的 Tkinter 参数？

Question

在循环中创建按钮实例后，如何更新单个按钮或标签？假设我想将“北”按钮的背景更改为“蓝色”。

?????????.config(bg = 'blue')

下面代码中“北”按钮的按钮名称是什么？

import tkinter as tk

def onbutton_click(label):
    print('selected ', label)

lst = ['North','South','East','West']
win = tk.Tk()
win.title = 'Compass'
for col,Direction in enumerate(lst):
    buttonName = tk.Button(win, text=Direction, command=lambda e=Direction: onbutton_click(e))
    buttonName.grid(row=0, column=col)

win.mainloop()

此代码来自 gms 回答的另一个问题 - 谢谢，这是一个很好的答案，非常清楚！ Tkinter create buttons from list each with its own function

Answer 1

在循环中创建按钮对象后，您需要对按钮对象进行某种引用才能访问和修改它们。

一个想法是将它们放在以方向为键的字典中：

import tkinter as tk
    
def onbutton_click(label):
    print('selected ', label)

lst = ['North','South','East','West']
win = tk.Tk()
win.title = 'Compass'

button_dict = {}

for col,Direction in enumerate(lst):
    buttonName = tk.Button(win, text=Direction, command=lambda e=Direction: onbutton_click(e))
    buttonName.grid(row=0, column=col)
    button_dict[Direction] = buttonName

button_dict['North'].config(bg='blue')

win.mainloop()

Answer 2

试试这个：

import tkinter as tk

def onbutton_click(label):
    print('selected ', label)
    if label == "North":
        # because "North" is the first item of `lst` we
        # know that we can use 0 as the idx
        buttons[0].config(text="new text here")

lst = ['North','South','East','West']
win = tk.Tk()
win.title = 'Compass'

# Create a list for all of the buttons
buttons = []

for col,Direction in enumerate(lst):
    buttonName = tk.Button(win, text=Direction, command=lambda e=Direction: onbutton_click(e))
    buttonName.grid(row=0, column=col)

    buttons.append(buttonName)

win.mainloop()

我创建了一个包含所有按钮和方向的字典，如下所示：{"North": <Button>, "South": <Button>}。然后我使用<dict>["North"] 来获取带有“North”标签的按钮。