如何在Tkinter中关闭拖放功能？

Question

我有一些代码：

from tkinter import *
from tkinter.dnd import Tester as DragWindow, Icon as Dragable

# Make a root window and hide it, since we don't need it.
root = Tk()
root.withdraw()
# Make the actual main window, which can have dragable objects on.
main = DragWindow(root)

def make_btn():
    # The functional part of the main window is the canvas.
    Dragable('B').attach(main.canvas)

def dragoff():
    pass  # What do I write here?

# Make a button and bind it to our button creating function.
B1 = Button(main.top, text='A', command=make_btn)
B1.pack()
B2 = Button(main.top, text='Drag Off', command=dragoff)
B2.pack()

root.mainloop()

我正在使用tkinter.dnd作为拖放功能。但我在关闭drag dnd drop时遇到问题。 所以，基本的想法是，当我点击B1时，会创建一个带有按钮的画布，我可以在其中移动它。当我单击B2时，我应该不能在画布中拖放

Answer 1

首先，需要保存Dragable实例的引用：

dragable_item = None

def make_btn():
    global dragable_item
    if dragable_item is None:
        dragable_item = Dragable('B')
        dragable_item.attach(main.canvas)

然后可以调用dragable_item.label.unbind("<ButtonPress>")禁用DnD：

def dragoff():
    if dragable_item:
        dragable_item.label.unbind("<ButtonPress>")