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()

我使用tkinter.dnd作为拖放功能。但我在关闭拖放功能时遇到了问题。所以，基本的想法是，当我单击B1时，会创建一个Canvas，其中有一个按钮，我可以在其中移动它。当我单击B2时，我应该无法在画布中拖放。

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)

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

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