events - Tkinter - 多个按钮的相同事件

Question

使用 Tkinter，我有很多按钮。我希望每次按下任何按钮时都会触发相同的回调函数。如何找出按下了哪个按钮？

def call(p1):
    # Which Button was pressed?
    pass

for i in range (50):
    B1 = Button(master, text = '...', width = 2)
    B1.grid(row = i*20, column = 60)               
    B1.bind('<Button-1>',call)

    B2 = Button(master, text = '...', width = 2)
    B2.grid(row = i*20, column = 60)               
    B2.bind('<Button-1>',call)

Answer 1

使用列表来引用动态创建的按钮和 lambda 来存储对按钮对象索引的引用。您可以确定单击了哪个按钮。在以下示例中，我使用 .cget("text")在按钮对象上演示访问按钮小部件。

import tkinter as tk

root = tk.Tk()
root.minsize(200, 200)

btn_list = [] # List to hold the button objects

def onClick(idx):
    print(idx) # Print the index value
    print(btn_list[idx].cget("text")) #Print the text for the selected button

for i in range(10):
    # Lambda command to hold reference to the index matched with range value
    b = tk.Button(root, text = 'Button #%s' % i, command = lambda idx = i: onClick(idx))
    b.grid(row = i, column = 0)

    btn_list.append(b) # Append the button to a list

root.mainloop()

或者，您可以使用绑定(bind)，然后从生成的事件对象访问小部件。

import tkinter as tk

root = tk.Tk()
root.minsize(200, 200)

def onClick(event):
    btn = event.widget # event.widget is the widget that called the event
    print(btn.cget("text")) #Print the text for the selected button

for i in range(10):
    b = tk.Button(root, text = 'Button #%s' % i)
    b.grid(row = i, column = 0)
    # Bind to left click which generates an event object
    b.bind("<Button-1>", onClick)

root.mainloop()