tkinter菜单栏和复选框保持打开状态

Question

我正在菜单栏的菜单中的tkinter中制作菜单栏，我有一些check_button，当点击其中一个check_button时，菜单关闭，但我想保持此菜单打开。我想知道是否有一种简单的方法。我正在制作一个地图编辑器，在我的菜单中，我选择显示或不显示地图的元素。

menubar = tk.Menu()
viewMenu = tk.Menu(menubar, tearoff = 0)
viewMenu.add_check_button(label = "Obstacles", varibale = test1)
viewMenu.add_check_button(label = "Ground", varibale = test2)
menubar.add_cascade(menu = viewMenu, label = "View")
win.config(menu = menubar) # win = tk.Tk()

Answer 1

下面的示例打开每次选中一个复选框时返回：

import tkinter as tk

root = tk.Tk()

test1, test2 = tk.BooleanVar(), tk.BooleanVar()

def cb():
    print(test1.get(), test2.get())
    root.tk.call('::tk::TraverseToMenu', root, 'v')

menubar = tk.Menu(root)
viewMenu = tk.Menu(menubar, tearoff = 0)
viewMenu.add_checkbutton(label = "Obstacles", variable = test1, command=cb)
viewMenu.add_checkbutton(label = "Ground", variable = test2, command=cb)
menubar.add_cascade(menu = viewMenu, label = "View")
root.config(menu = menubar) # win = tk.Tk()

root.mainloop()

查看更多信息here和here。

---

根据解释windows的特殊情况here的答案，可以编写如下非常相似的代码：

import tkinter as tk

root = tk.Tk()

if root._windowingsystem == 'win32':
    import ctypes

    keybd_event = ctypes.windll.user32.keybd_event
    alt_key = 0x12
    key_up = 0x0002

    def traverse_to_menu(key=''):
        if key:
            ansi_key = ord(key.upper())
            #   press alt + key
            keybd_event(alt_key, 0, 0, 0)
            keybd_event(ansi_key, 0, 0, 0)

            #   release alt + key
            keybd_event(ansi_key, 0, key_up, 0)
            keybd_event(alt_key, 0, key_up, 0)

else:
    #   root._windowingsystem == 'x11'
    def traverse_to_menu(key=''):
        root.tk.call('tk::TraverseToMenu', root, key)

test1, test2 = tk.BooleanVar(), tk.BooleanVar()
menubar = tk.Menu(root)
viewMenu = tk.Menu(menubar, tearoff = 0)
viewMenu.add_checkbutton(label = "Obstacles", variable = test1,
                            command=lambda : traverse_to_menu('v'))
viewMenu.add_checkbutton(label = "Ground", variable = test2,
                            command=lambda : traverse_to_menu('v'))
menubar.add_cascade(menu = viewMenu, label = "View")
root.config(menu = menubar) # win = tk.Tk()

root.mainloop()

key变量traverse_to_menu是'v'，因为Alt-V通过键盘打开菜单。在key中，需要是非修改键，默认情况下使用键盘打开菜单。